Refe rana® 40*411 ■Al f 3 ■ _ / fM i ° SZ 5 n, . { ■/O ]í]e. Referen*# FM 31-50 DEPARTMENT OF THE ARMYW FIELD MANUAL

— COMBAT IN FORTIFIED AND BUILT-UP AREAS

Pentagon Library (/'.NR-PL) ATTN: f.^'.-ary Decumont# nñ Room 1/S1S, Pentagan WasbingLon, DC 203WWH5§si

HEADQUARTERS, DEPARTMENT OF THE ARMY MARCH 1964

ütFtaíi«* Changes in force: C 2 FM 31-50 *C 2 CHANGE HEADQUARTERS DEPARTMENT OF THE ARMY No. WASHINGTON, D.C., £2 April 1970

COMBAT IN FORTIFIED AND BUILT-UP AREAS FM 31-50, T0 March 1964, is changed as follows: trapped. Mainly the serve three Page 5, paragraph 2. Subparagraphs b and c are purposes : superseded as follows : (1) They are defensive positions from which to protect training and rest areas. b. The material'hi this manual(2) They is applicable serve as to:storage areas for supplies (1) General war, to include a consideration and materiel. of the employment of nuclear and chemical muni- (3) They are used as hospitals and by com- tions; protection from duclear, chemical, and bio- mand groups and other critical agencies as shelters logical agents; and operations in nuclear, chemical, from air raids and bombardments. or biological environments. Page 9, paragraph 8b. In lines 8 and 9, “persist- (2) Limited war. \ ent toxic chemical agents” is changed to read “per- (3) S\ tabilitysistent-effect operations. chemical agent.” c. Users of this manual are encouraged to sub- Page 10. Paragraph 11 is superseded as follows : mit recommended changes and comments to im- prove the publication. Comments should be keyed 11. Obstacles to Airborne and Airmobile to the specific page, paragraph, and line of the Operations text in which the change is recommendedNReasons a. Obstacles may be placed on terrain in areas will be provided for each comment to insureunder- which would otherwise be suitable for parachute standing and complete evaluation. Comments drops or airlandings. Effective obstacles include should be prepared using DA Form 2028 (Recom- craters, posts, , immobilized or parked mended Changes to Publications) and forwarded vehicles, rock-filled oil drums, minefields, , direct to Commanding Officer, United States Army\ and persistent-effect toxic chemical agents. Such Combat Developments Command Infantry manmade obstacles should be integrated one with Agency, Fort Benning, Georgia 31905. Originators \another as well as with natural obstacles. of proposed changes which would constitute a \ 5. Helicopters may unload troops by use of troop significant modification of approved Army doc- ladders or by rappelling while hovering without trine may send an information copy, through com- landjng in obstacle-studded terrain. However, mand channels, to the Commanding General, once the helicopter-borne troops are on the ground, United States Army Combat Developments Com- their movement may be impeded by the obstacles mand, Fort Belvoir, Virginia 22060, to facilitate which prevent helicopters from landing. An air- review and followup. mobile capability gives the commander an option Page 8. Paragraph is addpd as follows: to bypass fortified areas and obstacles entirely. d. In Vietnam, well planned, extensive fortified Page 11. In paragraph 13c, line 9, “FM 7-11” and tunneled positions have been constructed by is changed to read “FM 7-10.” This same change the enemy in all areas—urban, rural, and wilder- is applied throughout the manual. ness. These positions range in size and complexity Page 11. Paragraph \Zd is superseded as from a one-man spider-trap to multi-level excava- follows: \ tions of 4 or 5 kilometers in length. Excepting d. For details on platoon missions see FM 7-10. those surrounding villages and hamlets, the forti- Page 11, paragraplv-14&, in line 1 delete “Bio- fications are usually well concealed and protected logical”; in line 8 delete'“and Biological”; in line with massive cover, and they are usually booby- 10 delete “and FM 3-10A”.

♦This change supersedes C 1, 18 May 1967. THE ARMY LIBRARY Pontascn Library (AMR-PL) TAGO 764A April 390-474.,„-70^^. DCCUmentS SeCtlOM WASHINGTON, D. C. Re-sm 1A51Û, Pentagon Wêshlngton, DC 20310-6050 C 2, FM 31-50 Page paragraph 14c. In lines 10 and 11 “non- and tunnel apertures are neutralized through fire persistent chemical agents" is changed to read and maneuver. The fire support element neu- “nonpersistent-effect chemical agent”. In lines Page 20, paragraph 29c. Line 21 is changed to 12 and 13 delete “or Biological.” read : “on orders of the element leader who is Page 12, paragraph \ok. In line 1 delete “or actually attacking.” biological”. Page 21, paragraph 306(1). Line 4 is changed Page IS. In paragraph 17». line 12, the follow- to read : “the with chemical munitions, ing sentence is added ¡-.During stability operations, antitank weapons, , démoli-” extensive foot patrolling by specialized units and Page 22. In paragraph 31, the following sen- organic elements offers the best opportunity to ob- tence is added at end of subparagraph 6 : Exten- tain timely, specific information of a fortified area. sive psychological operations (PSYOP) along Page 16. In paragraph 26, after the title and with non-lethal chemical munitions can have pro- before subparagraph a, the following sentence is found, positive affects in reducing the tenacity of added : During the attack of fortified positions the enemy. in heavily vegetated or very rough terrain, the Page 2U, paragraph 356(1). In lines 12 and .13 use of aircraft, bicycles, pack animals, and other “general line (GrOPL)” is changed to expedient means should be considered for gun plat- read “general outpost (GOP)” and in lines 13 and forms and transport of crew-served weapons and 14 “combat outpost line (COPL)” is changed to ammunition. read “combat outpost (OOP).” Page 16, paragraph 26». Line 1 is changed to Page 26. In paragraph 39, the following is added read “a. Mortars. The medium and heavy mor-”. at end of subparagraph c : Demolitions, emplaced Page 16. Paragraph 266 is superseded as during the preparation of the defense for such an follows : emergency, can be detonated to destroy key posi- b. Air Defense. For details on the employment tions if they are captured by the enemy. Continu- of organic nonair defense weapons in an air de- ous illumination can be of great assistance during fense role, and the employment of air defense night defense and counterattack. weapons, to include Redeye, see FM 7-10 and FM Page 27. In paragraph 41, after », a new sub- 7-20. paragraph is added as follows : Page 16, paragraph 26e, delete last sentence. ».1. During the decision making process, evalu- Page 17, paragraph 26<¿, delete last sentence. ation must be made as to the overall effects of con- Page 19, paragraph 26z. In lines 1,2, and 8 “non- templated operations on the welfare and attitude persistent chemical agents” is changed to read of civilians and the well-being of cherished or “nonpersistent-effect chemical agent” and in line necessary buildings such as national shrines and 10 “Persistent chemical agents” is changed to read monuments, water works, and medical facilities. “Persistent-effect chemical agents.” (1) Tactics which may provide the most Page 20, paragraph 286. Lines 1 through 9 are expedient military success may cause an adverse changed as follows : effect on the civilian populace, which in turn could 6. At company and platoon level, because of the complexity and concealment of some fortified prove to be more costly in both time and lives of areas, a unit conducting a reconnaissance in force friendly soldiers. Detailed analysis is necessary to must avoid alerting the periphery of the positions permit maximum neutralization or destruction of .and then being ambushed from all sides by the de- the enemy while minimizing adverse effects on fender. Utilization of point-type elements (at least noncombatant civilians. one for each platoon or a minimum of three for (2) Whether the area is attacked or by- each company regardless of the company forma- passed, the time and effort in meticulous and co- tion) normally will preclude the entire unit being ordinated planning can be well justified by the trapped and unable to employ supporting weapons relatively inexpensive rehabilitation of friendly effectively because of the proximity of friendly civilians from intact buildings as compared to the and enemy forces. In a coordinated attack, costly, drawn-out process of dealing with irate

2 ¡TAGO 764A C 2, FM 31-50 citizens from a partially or completely destroyed night in built-up areas require detailed and careful built-up area. planning. Page £8, paragraph 41. After subparagraph h, (6) The commander of an airmobile force as- a new subparagraph is added as follows: saulting a built-up area may be required to give special consideration for the safety of noncom- i. An airmobile assault of cities and urban areas batants within the area. The problem may be usually will require modification of techniques which are otherwise normal for an airmobile oper- especially acute in stability operations when the military-type force defending the built-up area ation in relatively unimproved or uninhabited is holding the civilian population as a mass hos- areas. Some special considerations for airmobile tage. In this situation, the airmobile force com- operations in built-up areas are given below ; for mander will base his plans on specific instructions general considerations for airmobile operations, from higher echelons. Once the airmobile opera- see FM 57-35. tion is initiated in a built-up area, the accom- ( 1 ) Landing areas for helicopters in built-up plishment of the mission for that operation re- areas may be extremely limited. Open parks, broad mains the commander’s primary consideration; streets, and plazas may be obvious areas suitable therefore, any restrictions on the use of his full for helicopter landing, but the suitability of such combat power must be clearly defined and under- areas will also be obvious to the defender and stood by all concerned before the start of the air- probably will be well covered by fire or studded mobile operation. with obstacles. (7) After landing, troops in an airmobile as- (2) A roof should not be used for helicopter sault of a built-up area will be employed as dis- touchdown until the soundness of the structure cussed in chapter 6. has been verified. This is especially important Page 29. Following paragraph 43a, a new sub- when structures have been subjected to preassault paragraph is added as follows : fires which may have weakened them. Prior to an a.l. The judicial use of firepower provides an airmobile assault, engineer teams or pathfinders opportunity to defeat the enemy without extensive may be used to determine the loadbearing capabil- civilian casualties and extensive damage to build- ity of certain roofs, but such preassaul t reconnais- ings. Precision firing and maximum control of sance must be done without disclosing the nature fires can preclude turning friendly civilians of the impending operation. against the attacker. The time and effort spent to (3) Rappelling techniques and trooper conserve the life of noncombatants and nonmili- ladders can be used to unload troops from heli- tary property can be well rewarded by the small copters in built-up areas as in most other areas, effort subsequently required to reestablish a and these are excellent means of delivering troops friendly populace as compared to the effort re- to rooftops for top-to-bottom search of buildings quired to reestablish a hostile one. (para 69). Consideration must be given to the vulnerability of helicopters and troops to sniper Pages 29 and 30, paragraph 436. In line 3 delete fire when utilizing either of these two techniques. “or biological”. In line 5 delete “and biological”. (4) Snipers are a particular hazard for heli- In lines 7 and 8, delete “such as incubation time, copters operating in built-up areas. Buildings and delay in casualty production”. rubble offer excellent cover and concealment for Page 30, paragraph 43c. In lines 5 and 6 delete snipers, and intensive fires will be required to “and biological”. Delete last sentence of subpara- neutralize them. Such fires will include close air graph c. support, aerial, artillery, fires from armed heli- Page 30, paragraph 47. Last sentence of sub- copters, indirect fires, and (to a limited extent paragraph a is changed to read : “Civilians may initially) direct fires from ground weapons. be hired on a voluntary basis, to prepare fortifica- (5) Relatively good visibility is required for tions and to work on other labor projects ; however, helicopters to avoid special hazards in built-up it should be assumed that enemy agents will be areas such as the irregular heights of buildings, among them. This risk must be weighed against the powerlines, and antennas. Airmobile operations at labor gained.”

TAGO 764A 3 C 2, FM 31-50 Page 32, paragraph 50. The following is sub- Page 49. Paragraph 7o. After e, the following stituted for the first two lines of subparagraph a: subparagraph is added : a. To preclude casualties and damage to struc- /. Stability Operations. Denying the guerrilla tures, throughout the attack maximum use is made or insurgent access to the built-up area is of prime of PYS'OP and non-lethal chemical munitions. importance. Along with other free-world forces, The attack of a built-up area may be divided into maximum use is made of indigenous military, three phases. paramilitary, and police forces to establish and Page 37. In paragraph 626, line 7, after “and maintain appropriate security and traffic control penetrating power”, the following is added : “The measures. Specific areas, specific missions, and ex- light antitank weapon (LAW) provides a direct plicit coordination measures must be given to all means for delivering non-lethal chemical muni- agencies involved in populace control and defense tions on point or small area targets at a range of of the built-up area. Tests and rehearsals will in- 20-750 meters. The munition functions on impact, sure maximum effectiveness. and an effective agent concentration within a 5- Page 50, paragraph 77c?. The first sentence is meter radius can be established within 5 seconds changed to read : after detonation.” d. All echelons of units, to include air defense Page 37, paragraph 62cZ. Line 1 is changed to elements, are assigned specific areas to be read “if. 'Mortars. Both heavy and medium”. defended. Page Ifi. Paragraph 71c is superseded as follows : Page 50, paragraph 79a. In line 3 “(COPL)” is c. When an urban area has been seized by in- changed to read “ (COP) ”. surgent or guerrilla forces, an evaluation has to be Page 50. In paragraph 79a, line 10, the following made as to whether it is more advantageous, from sentence is added: “During stability operations, both a tactical and stability operation perspective, traffic control points, checkpoints, and other secu- to recapture it with unrestricted force or to recap- rity points are made an integral part of the ture it using other techniques. The decision as to security echelon.” the amount of force and the specific techniques to be used to recapture the area is based on analysis Page 50, paragraph 79c. In line 1 “COPL” is of the psychological impact on the enemy, noncom- changed to read “COP”. batant civilians, and friendly troops; the safety of Page 52, paragraph 80c(3). In line 1 “81-mm” civilians and friendly troops; the destruction of is changed to read “medium”. buildings; and the military requirements for other Page 52, paragraph 82. In line 3 “COPL” is impending tactical operations. changed to read “OOP”. Page Ifi, paragraph 71. After c, the following Page 54, paragraph 85a. In line 5 “include direct subparagraph is added : fires” is changed to read “include both direct and d. Material contained in this section must be indirect fires”. Delete lines 6 and 7, and in line 8 supplemented by reference to FM 31-16 and FM “barrages” is changed to read “artillery targets.” 100-20. Page 54, paragraph 86a. In lines 1 and 3 “4.2- Page J$, paragraph 73. After c, the following inch” is changed to read “heavy”. subparagraph is added as follows : ■ Page 54. Paragraph 866 is superseded as d. Small, well-trained, thoroughly rehearsed pa- follows : trols can be used simultaneously with PSYOP and 6. Aerial Artillery and Air Defense Weapons. chemical munitions to demoralize and defeat with For discussion of aerial artillery and air defense minimal force and destruction the defenders of a weapons, see FM 7-10, FM 7-20, FM 44-1, and built-up area. These patrols should be given mis- FM 57-35. sions to neutralize key personnel and agencies through simple, covert techniques. Low-signature Page 55, paragraph 87. At end of paragraph the weapons and silent-kill techniques, together with following sentence is added : Engineers also pre- PSYOP and non-lethal chemical munitions, can pare landing sites for aircraft on both the ground enhance breaking the will of the enemy with mini- and key buildings for use during contingency mum violence. operations.

4 TAGO i764A C 2, FM 31-50 Page 55, paragraph 90. At end of paragraph, the FM 31-23, Stability Operations—U.S. Army following sentence is added : Rehearsals are im- Doctrine portant when aircraft are used, when civilians are FM 44-1, U.S. Army Air Defense Artillery still in the area, or when other than U.S. forces are Employment involved. (C)FM 100-20, Field Service Regulations: Page 55, paragraph 91&. In lines 5 and 6 “(to Internal Defense and Internal Development include the Davy Crockett) ” is deleted. (IDAID) (U) Page 56, paragraph 92. At end of paragraph, the Page 59, appendix II. Paragraph 26(2), sub- following sentence is added : During stability op- paragraph (6) is superseded as follows : erations, the counterattack is greatly influenced (6) Techniques of entry and search of by considerations discussed in chapter 6. buildings, to include use of helicopters in built-up Page 57, appendix I. “FM 3-10A” with title is areas. deleted, “FM 7-11” with title and “FM 7-15” with Page 60, paragraph 3a(l) (d). In line 2 delete title are superseded by “FM 7-10, The Rifle Com- “any” and at the end of line 3, add “such as air pany, Platoons, and Squads”; and “FM 23-20” defense weapons.” with title is deleted. Page 60. Paragraph 36(2) after (¿), the follow- Page 58, appendix I. In numerical sequence, the ing subparagraph is added : following references are added : (e) Development of proficiency in the use FM 19-4, Military Police Support, Theater of special-purpose or additional weapons, such as of Operations air defense weapons. By Order of the Secretary of the Army :

W. C. WESTMORELAND, General, United States Army, Official: Chief of Staff. KENNETH G. WICKHAM, Major General, United States Army, The Adjutant General.

Distribution : To be distributed in accordance with DA Form 12-11 requirements for Combat in Fortified and Built-Up Areas.

TAGO 764A 5

U.S. COYERHHCNT PRIHTIHC OFFICE. 1970 V m

¿EFEHFNCF

FM 31-50 C 1

CHANGE HEADQUARTERS DEPARTMENT OF THE ARMY No. 1 WASHINGTON, D.C., 18 May 1967 COMBAT IN FORTIFIED AND BUILT-UP AREAS FM 31-50,10 March 1964, is changed as follows : Page 3, paragraph 2. Subparagraphs b and c the ground, their movement may be impeded by are superseded as'follows : the obstacles which prevent helicopters from b. The material\s applicable to nuclear and landing-. An airmobile capability gives the com- nonnuclear warfare ¡'employment of, and protec- mander an option to bypass fortified areas and tion from, chemical, biological, and radiological obstacles entirely. agents; and stability operations. Page 11. Paragraph IZd is superseded as fol- c. Users of this manuamre encouraged to sub- lows: mit recommendations to iipprove its clarity or d. For details on platoon missions see FM accuracy. Comments should beJreyed to the specific 7-15. page, paragraph, and line ofNiie text in which Page 11, paragraph 14c. In lines 10 and 11 “non- the change is recommended. Reasons should be persistent chemical agents” is changed to read provided for each comment to insure understand- “nonpersistent-effect chemical agent.” ing and complete evaluation. Cormnents should be Page 16, paragraph 26a. Line 1 is changed to forwarded direct to Commanding Officer, United read “a. Mortars. The medium and heavy mor-” States Army Combat DevelopinentsNCommand Infantry Agency, Fort Benning, Ga. 31905. Page 16. Paragraph 26J is subperseded as fol- lows: Originators of proposed changes whiclK^would b. Air Defense. For details on the employment constitute a significant modification of appi^oved Army doctrine may send an information copy, of organic nonair defense weapons in an air de- fense role, and the employment of air defense through command channels, to the Commandmg weapons, to include Redeye, see FM 7-11. General, United States Army Combat DevelopX ments Command, Fort Belvoir, Ya. 22060, to Page 16, paragraph 26c, beginning on. line 9, facilitate review and followup. ^delete the last sentence. Page 9, paragraph 8b. In lines 8 and 9 “persist- _ 'age 17, paragraph 26a!. top of page, beginning ent toxic chemical agent” is changed to read online 9 delete the last sentence. “persistent-effect chemical agent.” Paÿe 18, paragraph 26/. In line 6 “FM 7-10” Page 10. Paragraph 11 is superseded as follows : is changed to read “FM 7-11.” Page IS, paragraph 26i. In lines 1, 2, and 8 “non- 11. Obstacles to Airborne and Airmobile persistent \hemical agents” is changed to read Operations “nonpersistent-effect chemical agent” and in line a. Obstacles may be placed on terrain in areas 10 “Persistent\hemical agents”, is changed to read which would otherwise be suitable for parachute “Persistent-effect chemical agents.” drops or airlandings. Effective obstacles include Page 24: paragraph 25i(l). In lines 12 and 13 craters, posts, barbed wire, immobilized or parked “general outpost line (GOPL)” is changed to vehicles, rock-filled oil drums, minefields, abatis, read “general outpostv/GOP) ” and in lines 13 and and persistent-effect toxic chemical agents. Such 14 “combat outpost LINE (COPL)” is changed manmade obstacles should be integrated one with to read “combat outpostv (COP).” another as well as with natural obstacles. Page 28. Paragraph 41zis added as follows : b. Helicopters may unload troops by use of i. An airmobile assault of cities and urban areas trooper ladders or by rappelling while hovering usually will require modification of techniques without landing ' in obstacle-studded terrain. which are otherwise normal for\m airmobile op- However, once the helicopter-borne troops are on eration in relatively unimproved or uninhabited Î-PL) TAGO 28A—July 300-465.. -67 ATTN: f.V.'.Vr.:'; -3jcumanteSection Ream lAoio, Pentagon Washington, DC 20310-605Q \ areas. Some special considerations for airmobile (6) The commander of an airmobile force operations in built-up areas are given below; for assaulting a built-up area may be required general considerations for airmobile operations, to give special consideration for the see FM 57-35. safety of noncombatants within the area. ( 1 ) Landing areas for helicopters in built-up The problem may be especially acute in areas may be extremely limited. Open stability operations when the military- parks, broad streets, and plazas may be type force defending the built-up area obvious areas suitable for helicopter land- is holding the civilian population as a ing, but the suitability of such areas will mass hostage. In this situation, the air- also be obvious to the defender and will mobile force commander will base his probably be well covered by fire or stud- plans on specific instructions from higher ded with obstacles. echelons. Once the airmobile operation (2) A roof should not be used for helicopter is initiated in a built-up area, the accom- touchdown until the soundness of the plishment of the mission for that opera- structure has been verified. This is espe- tion remains the commander’s primary cially important when structures have consideration; therefore, any restrictions been subjected to preassault fires which on the use of his full combat power must may have weakened them. Prior to an be clearly defined and understood by all airmobile assault, engineer teams or path- concerned before the start of the airmo- finders may be used to determine the load- bile operation. bearing capability of certain roofs, but (7) After landing, troops in an airmobile as- such preassault reconnaissance must be sault of a built-up area will be employed done without disclosing the nature of the as discussed in chapter 6. impending operation. Page 37, paragraph 37c?. Line 1 is changed to (3) Rappelling techniques and trooper lad- read “d. Mortars. Both heavy and medium” ders can be used to unload troops from Page 4-6. Paragraph 'lid is added as follows: helicopters in built-up areas as in most d. Material contained in this section must be other areas, and these are excellent means supplemented by reference to FM 31-16 and of delivering troops to rooftops for top- 100-20. to-bottom search of buildings (para 69). Page '50, paragraph lid. The first sentence is Consideration must be given to the vul- changed to read : nerability of helicopters and troops to d. All echelons of units, to include air defense sniper fire when utilizing either of these elements, are assigned specific areas to be defended. two techniques. Page 50, paragraph 79a. In line 3 “ (COPL)” is (4) Snipers are a particular hazard for heli- changed to read “ (COP).” copters operating in built-up areas. Build- Page 50, paragraph 79c. In line 1 “COPL” is ings and rubble offer excellent cover and changed to read “COP.” concealment for snipers, and intensive Page 52, paragraph 80c(3). In line 1 “81-mm” fires will be required to neutralize them. is changed to read “medium.” Such fires will include close air support, aerial artillery, suppressive fires from Page 52, paragraph 82. In line 3 “COPL” is armed helicopters, indirect fires, and (to changed to read “COP.” a limited extent initially) direct fires from Page 54, paragraph 85. In line 5 “include direct ground weapons. fires” is changed to read “include both direct and (5) Relatively good visibility is required for indirect fires.” Delete lines 6 and 7, and in line 8 helicopters to avoid special hazards in “rages” is changed to read “Artillery targets.” built-up areas such as the irregular Page 54, paragraph 86a. In lines 1 and 3 “4.2- heights of buildings, powerlines, and an- inch” is changed to read “heavy.” tennas. Airmobile operations at night in Page 54- Paragraph 866 is superseded as built-up areas require detailed and care- follows : ful planning. 6. Aerial Artillery and Air Defense Weapons.

2 TACO 28A For discussion of aerial artillery and air defense Page 59, paragraph 22» (2), subparagraph (2») is weapons, see FM 7-11, FM 7-20, FM 44-1, and superseded as follows : FM 57-35. (2>) Techniques of entry and search of Page 55, paragraph 91Z>. In lines 5 and 6 “ (to in- buildings, to include use of helicopters clude the Davy Crockett) ” is deleted. in built-up areas. Page 57, appendix I. FM 23-20 and title is Page GO, paragraph 3a(l) (c2). In line 2 delete deleted. “any” and at the end of line 3 add “such as air Page 58, appendix I, the following is added. defense weapons.” FM44-1 U.S. Army Air Defense Artillery Employment Page 60. Paragraph 32» (2) (e) is added as (C) FM 100-20 Field Service Regulations : follows : Internal Defense and (e) Development of proficiency in the use Internal Development of special-purpose or additional weap- (IDAID) (Ü) ons, such as air defense weapons. By. Order of the Secretary of the Army :

HAROLD K. JOHNSON, General, United States Army, Official: Chief of Staff. KENNETH G. WICKHAM, Major General, United States Army, The Adjutant Generad.

Distribution : To be distributed in accordance with DA Form 12-11 requirements for Combat in Fortified and Built-Up Areas.

TAGO 28A 3

US GOVERNMENT PRINTING OFFICE: 1967 v 'ixf\ *FM 31-50

FIEL MANUAL! HEADQUARTERS DEPARTMENT OF THE ARMY NO. Sl-'öO WASHINGTON, D.C., 10 March 196b

COMBAT IN FORTIFIED AND BUILT-UP AREAS

Paragraphs Page PART ONE COMBAT IN FORTIFIED AREAS CHAPTER I. INTRÔpUCTION 1,2 3 CHAPTER 2. FORTIFICATIONS Section I. Types of fortifications 3-5 4 II. Organization of fortified areas 6, 7 8 III. Obstacles....\. 8-11 9 CHAPTER 3. ATTACK OFV FORTIFIED AREA Section I. General \. 12-19 11 II. Planning V .20-27 14 III. Conduct of the attack 28-31 20 CHAPTER 4. DEFENSE OF A FORTIFIED AREA Section I. General 32-34 23 II. Planning \ 35-37 24 III. Conduct of the defense's.. 38, 39 26 PART TWO COMBAT IN BUILT-UPVREAS CHAPTER 5. GENERAL 'S 40-47 27

6. ATTACK OF A BUILT-UPVREA Section I. General \. 48-50 32 II. Planning .\. 51-64 33 III. Conduct of the attack S. 65-67 38 IV. House-to-house fighting \ 68-70 40 V. Counterguerrilla operations V 71-73 46 CHAPTER 7. DEFENSE OF A BUILT-UP AREAS Section I. General \ 74-76 49 II. Planning \. 77-90 50 III. Conduct of the defense ,\ 91, 92 55 APPENDIX I. REFERENCES \ 57 II. TRAINING 59 INDEX 61

/ This manual supersedes FM 31-50, 24 July 1952, including C 1, 1 December 1954 and C 2, 18 November 1955.

1

PART ONE COMBAT IN FORTIFIED AREAS

CHAPTER 1 INTRODUCTION

1. Purpose nature of operations in fortified and built- This manual provides guidance to com- up areas at lower levels. b. The material is applicable to either nu- manders and staff officers in the fundamental clear or nonnuclear warfare. doctrine and tactical principles of combat in fortified and built-up areas. c. Users of this manual are encouraged to submit recommended changes or comments to improve the manual. Comments should 2. Scope be keyed to the specific page, paragraph, a. This manual is divided andinto linetwo ofparts. the text in which the change is Part one describes the characteristics, tac- recommended. Reasons should be provided tical considerations, and doctrine and tech- for each comment to insure understanding niques for the tactical employment of units and complete evaluation. Comments should in fortified areas. Part two covers the same be forwarded direct to the Commanding material applicable to built-up areas. The Officer, U.S. Army Combat Developments material is focused largely on operations Command Infantry Agency, Fort Benning, below division level to emphasize the unusual Ga. 31905.

3 CHAPTER 2 FORTIFICATIONS

Section I. TYPES OF FORTIFICATIONS

3. General as Strasbourg, Metz, Belfort, and Verdun, by surrounding each city a. Fortifications provide a base for offen- with strong forts. sive operations or a series of strong defensive positions for the protection of vital areas. They cause the attacker to mass and present 4. Fortifications in World War II and Korea a profitable target and to dissipate his com- a. Observations and studies of the oper- bat power in the task of reducing the fortifi- ations of convinced many cations, thereby making him more vulnerable European military leaders that strong, per- to counterattack. manent fortifications were essential to the b. The use of fortifications in war is as old defense of their countries. From this con- as war itself. Through the ages, armies, cept there developed a series of fortified lines fighting both offensive and defensive battles, such as the Maginot Line in France, the have employed various types of fortifications Siegfried Line in Germany, and the Manner- constructed with many kinds of material. heim Line in Finland. These lines, however, Logs, earth, rocks, concrete, and steel have had numerous structural differences. been employed in numerous forms to con- (1) The Maginot Line consisted of vast, struct walls, , bunkers, pillboxes, tiered underground forts, pillboxes, , and reinforced trenches. (fixed and disappearing), and (1) History records several concepts for antipersonnel and antitank barriers. providing protection for the defender Reliance was placed on the almost and an obstacle to the attacker. indestructible nature of the fortifi- One system is the \mea.r, fortified belt. cations themselves. The Siegfried This was carried to an extreme by the and Mannerheim Lines, on the other Chinese when they built the Great hand, were built with an eye toward Wall. While the fortified belt has capitalizing on and strengthening been employed in modern times, the the natural defenses afforded by the trend has been toward securing terrain. Deep belts of artificial ob- greater depth. Perhaps the best stacles reinforced the natural ob- known examples of the fortified zone stacles or covered the avenues of are the Maginot Line of World War approach where natural obstacles I and the Siegfried Line of World were weak or nonexistent. Pillboxes War II. and gun emplacements, located in (2) Another and more frequently em- width and depth, were positioned to ployed system of fortifications is the cover the obstacles, to be mutually fortified locality. The French ex- supporting, and to provide a continu- ploited this method from the time of ous band of interlocking fires. Fig- Louis XIV when his famous engineer, ure 1 shows a typical example of a Vauban, fortified frontier cities, such German emplacement. 4 &

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4 * > . * -J* % » TO -jV- •.•T— ' - w* r* Äi rr X. C*-v » ».V. SK

I\ irfÄ . I ' _TT' -

Figure 1. on the Siegfried Line with stepped construction in the .

(2) The great difference between the to slow or blunt the enemy attack, Maginot and Siegfried Lines was not Strong, mobile armies held behind so much in the manner in which they the line in reserve would then coun- were constructed as in the concept terattack and destroy the weakened of their use. The Maginot Line was enemy forces. The accent here was based on the static defense principle. on using fortifications to set up the The enemy would be held at bay by enemy for destruction by counter- the strength of the fortifications and attack, not on letting him destroy the firepower they put forth. Pene- himself by attacks against the trations would be counterattacked fortifications. Figure 2 illustrates by local forces sallying forth from the manner in which the Siegfried their underground shelters. Little Line was laid out. or no thought was given to large- scale counterattacks. Conversely, b. World War II saw many other variations the Siegfried Line emphasized the in the type and use of fortifications. The offensive. As a result, the purpose most important were those of the Japanese of obstacles and emplacements was and Russians. 5 620 630 640

650 660 670 67 5^

660 650 -640

630

620 610

X* X 600 x *

590

620

LEGEND Direction of attack Pillbox and directions of fire. NOTE: NOT TO SCALE X X X X Barbed wire o oo Antitank obstacles.

Figure Diagram of a portion of the German Siegfried Line (schematic).

(1) The Japanese normally employed movement from one part of the area the fortified locality principle. Maxi- to another. Because of the rugged mum use was made of the terrain terrain often utilized and the charac- features offering the best natural teristic lack of strong, mobile re- defense. Pillboxes and bunkers serves, the Japanese seldom counter- were made of concrete, earth, and attacked with other than local logs. Tunnels were used extensively reserves. In this respect, their use and were often connected to provide of fortifications resembled that of an underground system which pro- the French. tected personnel, supplies, and com- (2) The Russian scheme of defense com- munications, and permitted covered bined the fortified locality principle 6 with the German emphasis on strong front. Pillboxes, gun emplacements, counterattacks. Key terrain features underground bunkers, and shelters were organized for all-around defense were made from the strongest avail- by units of approximately battalion able material. Antitank ditches, size. These centers of resistance minefields, barbed wire, and other were deployed irregularly along a obstacles were used to protect the

,500-2,000 M Direction of attack

-A

V- -a x. Xx* _n S ’S. *n. 'O0

fas* ¥ PCL \ 'lc

¥ h F' ■n. 2

N rr Ir

-JLTV. & a "4

LEGEND " Covered trench.

Communicating trench.

jwuv Firing trench or dummy.

-—Antitank or obstacle.

Wire obstacle, i Minefields not shovm.

x/ Pillbox (with direction of fire.)

XX X Barbed wire. .—► Antitank weapon.

Figure 8. Diagram oj a Russian of a center oj resistance (schematic). 7 strongpoints and impede the attack- techniques adopted were the same as those er’s progress through the gaps be- employed in World War II. Rocks, logs, and tween them. These gaps were cov- dirt were used to construct bunkers, gun em- ered by direct and indirect fire placements, and networks of tunnels. These weapons located within one or more fortifications covered all key terrain up to a strongpoints. Often, these gaps depth of some 30,000 meters. were lightly covered by obstacles to induce the attacker to commit his force into what appeared to be a 5. Types of Fortified Areas weak point in the defender’s line. A fortified area is one containing numerous The appearance was deceptive be- defensive works. These may include forti- cause, once committed in the gap, fied weapon emplacements or bunkers, pro- the attacker found himself faced on tected shelters, reinforced natural or three sides by strong fortifications manmade caves, entrenchments, and ob- and subjected to devastating fires stacles. Depending on its location, extent, from many weapons. Then, weak- and depth, a fortified area and its ports may ened by the effects of these fires, be classified as follows: he would be struck by a counter- a. Fortified Locality. A grouping of de- attack launched by mobile forces fensive works about a single location, either that had been held in reserve behind without regard to any other defensive sys- the rows of strongpoints. Defense tem, or as a part of a large defensive system. in depth was secured by building b. Fortified Position. A series of strongly three irregular rows of strongpoints organized localities disposed in width and' separated by 10,000 to 15,000 meters. depth in such a manner as to be mutually See figure 3 for a schematic diagram supporting. Exceptionally, it may be a of a Russian fortified center of single, strongly organized locality. resistance. c. Fortified Belt. A linear grouping of c. Late in 1951 when the war in Korea fortified positions. became stabilized, the Chinese and North d. Fortified Zone. A system of fortified Korean Communists and US-UN forces positions extending laterally and in depth, improved their lines until they eventually normally consisting of two or more fortified became fortified positions. In general, the belts.

Section II. ORGANIZATION OF FORTIFIED AREAS

6. General attacking forces. Consistent with the fre- a. Fortified works of some nature are quent movement of units on the modern always constructed when military forces battlefield, mostly log or earth bunkers and have a defensive mission. Depending on the field fortifications will be used. time and resources available for construc- b.. Log or earth bunkers, emplacements, tion, fortified works may range in complexity and shelters, which may be constructed of from simple positions hastily prepared with locally available materials, provide good pro- locally available material to large permanent- tection for personnel and weapons, depending type works in organized and integrated belts upon the depth of construction and the or zones. Permanent-type works include strength and thickness of the overhead concrete bunkers with thick walls, fixed em- cover. They afford a degree-of protection brasures or steel turrets, intricate under- from nuclear weapons effects and chemical ground passages, and elaborate troop and biological agents. For details of con- quarters. These are unlikely to be used in struction, see FM 5-15. normal operations because of their great expense in time, material, and manpower, 7. Organization of Fortified Areas and the fact that they may be bypassed by a. The organization of a fortified locality 8 is based upon the retention of a specific ter- d. A fortified zone is organized in depth rain feature or an important installation. with two or more belts. Flank security is A perimeter defense is organized to provide provided by tying the fortified zone in with all-around defense. Bunkers are mutually a natural terrain barrier. A typical fortified supporting and are sited so that zone includes field fortifications 5,000 to all portions of the perimeter can be covered 10,000 meters in front of the first fortified by fire. Maximum use is made of obstacles, belt. These are manned by security forces including wire entanglements, mines, and to deceive, disorganize, and delay the at- various antitank obstacles. tacker; inflict casualties; and cause him to 6. Fortified positions are organized in a make frontal attacks on the fortified belt. manner similar to fortified localities, except Security forces occupy key terrain features that they are usually wider and possess or cover important road nets to attempt to greater depth. A perimeter defense is not force the attacker to deploy his forces pre- normally established; however, all-around maturely, after which the security forces defense is provided by reserve forces and the withdraw to from becoming decisively occupation of supplementary positions. engaged. Belts are usually located 10,000 c. Fortified belts form the backbone of a to 15,000 meters apart to force the attacker fortified area. ■ They are designed to stop to displace his supporting weapons before the enemy by delivering integrated fires assaulting the next belt. This delay tends from protected weapons emplacements. to destroy the continuity of the attack, and Fortified belts are usually 2,000 to 4,000 allows the defender additional time to re- meters in depth, with individual bunkers group his forces and launch counterattacks and emplacements within each belt posi- to restore the original position. The area tioned to cover all approaches into the between fortified belts contains numerous area. Mutual support is provided between fortified localities and other defenses at bunkers. Reserves in shelters at strategic critical points so as to impose maximum locations within the fortified belt are used delay and attrition on forces that penetrate for counterattack against attacking forces the fortified zone. that succeed in penetrating it.

Section III. OBSTACLES

8. General obstacles with persistent toxic chemical а. Both natural and manmade obstacles agents such as liquid VX will provide in- are used .extensively in fortified areas. creased effectiveness. Natural obstacles are exploited to the maxi- mum, and are extended, improved, and rein- forced by artificial obstacles. The nature of 9. Antipersonnel Obstacles the principal threat, whether dismounted, Barbed wire entanglements, trip flares, armored, mechanized, airborne, or a combina- antipersonnel mines, flame field expedi- tion of several of these, will largely determine ents, and warning devices strengthen the the character of the obstacles to be con- defense and help protect the defender from structed. Obstacles are employed to canalize surprise attack or infiltration at night. and slow the enemy and cause him to deploy Such obstacles should be close enough to the prematurely. fortification for adequate surveillance by б. Obstacles are often positioned to sepa- night or day, but beyond effective hand rate armor from infantry and thus render range. Nuisance minefields, booby- each element vulnerable to defeat. Ob- traps, and persistent chemical agents are stacles designed to impede both armor and also effective against personnel and may infantry are more effective than either anti- delay the attacker’s use of an area or installa- mechanized or antipersonnel obstacles em- tion immediately after friendly troops have ployed separately. Contamination of these withdrawn.

719-500 0-64 -2 9 10. Antimechanized Obstacles Antitank minefields, nuisance minefields, * demolitions, ditches, and structures of logs, -wW concrete, or steel are employed to halt or m delay wheeled and tracked vehicles long- enough for antitank fire to destroy them (figs. 4 and 5). « "H

JW+i'KZ 4 ••5

Figure 5. Steel rail obstacles.

11. Antiairborne and Antiairlanded Obstacles Obstacles are placed on suitable landing V M K fields and parachute drop zones to demolish aircraft in landing and impede movement in the area by parachute troops. Effective 7*4 k obstacles include craters, posts, barbed wire, Ä2T immobilized or parked vehicles, rockfilled oil ^ 7 ». drums, minefields, felled trees, and persistent toxic chemical agents such as VX alone or Figure U- Dragon’s teeth, showing five double roivs. integrated with other obstacles.

10 CHAPTER 3 ATTACK OF A FORTIFIED AREA

Section I. GENERAL 12. General 14. General Considerations This chapter deals primarily with the at- a. In attack of a fortified area, the de- tack of a fortified area consisting of one or fender has the advantage of greater pro- more fortified belts with mutually supporting tection against all types of fire. His bunkers and formidable obstacles. The area prepared obstacles, carefully planned fires, is of sufficient width to prevent bypassing and thoroughly rehearsed counterattack and requires the employment of one or more plans give him additional advantages. For maneuver battalions. these reasons, enemy fortified areas are, when possible, contained by minimum forces .13. Mission while the main force bypasses and continues a. The mission of the attacking echelon the advance to deeper, more decisive may include the seizure of terrain objectives objectives. 'that will assist in making the penetration of b. The use of chemical, biological, and the fortified area and assist the passage of nuclear weapons in the attack of a fortified an exploiting force. A nuclear preparation area will supplement the effects of other may permit the passage of the exploiting fires, reduce the mutual support required force prior to . the time the penetration is between bunkers, and facilitate bunker completed. In a nonnuclear situation, the destruction. The ability of napalm to burn attacking echelon is normally required to off camouflage and produce incendiary clear the enemy from the assigned zone of damage, and of chemical and biological action. agents to penetrate into fortifications, favors b. The battalion is the basic maneuver use of these agents (FM 3-10 and FM 3-10A). element and may participate in the brigade See paragraph 26g for a discussion of nuclear attacking echelon or reserve. When in the weapons effects. attacking echelon, the battalion is normally c. There are certain disadvantages to de- assigned a terrain objective or objectives. fending a fortified area. The defender is Missions for reserve battalions are essen- tied to a fixed position; this permits the tially the same as in other offensive attacker to determine accurately the de- operations. fender’s disposition and weaknesses, after c. Rifle companies will also be assigned which the attacker can systematically missions as part of the attacking echelon or maneuver to destroy the position by fire, reserve. Attacking rifle companies are explosives, and incendiaries, or render the usually assigned bunkers as intermediate position ineffective through the production objectives and terrain features as final of casualties by the use of nonpersistent objectives. Final objectives for rifle com- chemical agents. The position may be neu- panies are designated to facilitate reorgani- tralized through the use of chemical or zation and consolidation of the battalion biological incapacitating agents. objective (FM 7-11). For details of employ- d. The attack of a fortified area follows the ment of armor units, see FM 17-1. basic principles of offensive operations; how- d. For details on platoon missions see para- ever, greater emphasis is placed upon graphs 28 through 31 and FM 7-15. detailed planning, special training and re- 11 hearsals, increased fire support, 'and use of h. Airmobile and joint airborne forces may special equipment. The degree of special be used in conjunction with other attacks preparation depends upon the character and of the fortified area principally to block the extent of the defense. movement of large enemy reserves, isolate e. The integration of psychological warfare and/or assault strongpoints, and attack operations in the attack of a fortified area is fortifications from the rear. worthy of special consideration. Psychologi- i. Unless needed by the attacker, captured cal warfare units can be used to cause armament is moved or destroyed and forti- confusion and reduce the defender’s deter- fications are demolished to prevent their use mination to fight. For details of psychologi- by the defender if recaptured. After a cal operations, see FM 33-5. bunker is captured, it should be damaged enough to render it useless to the defender 15. Special Considerations should he recapture it. Bunker firing em- Special considerations in the attack of a brasures are usually not oriented so they fortified area are as follows: would assist the attacker in defending a. A primary purpose of a fortified area is against counterattack. Troop shelters, to cause the attacker to mass and present a however, may be useful for this purpose profitable target. Plans for the attack must minimize this danger, consistent with the and are therefore retained intact. accomplishment of the assigned mission. j. The capture of key bunkers may provide Opportunities to create tactical surprise information which is applicable to, and may should not be overlooked (FM 7-20). assist in, the seizure of similar bunkers; b. Detailed intelligence is required upon for example, information on communication, which to base plans, training, and rehearsals. obstacles, direction and the internal defen- c. Planning and preparation are central- sive characteristics of fortifications. ized, but the execution is decentralized. k. If the use of chemical or biological d. Detailed fire planning includes the co- agents is authorized, careful consideration ordination of all available fires such as must be given to weather conditions. These , combat engineer vehicles, self- conditions will influence the effectiveness propelled artillery, antitank weapons, and of such an attack as well as troop safety. close air support by Air Force aircraft and Army air vehicles arid weapons. 16. Intelligence e. The area selected for penetration must a. The basic intelligence and counterintel- be isolated from the remainder of the forti- ligence principles applicable to preparing fied area. Nuclear fires are particularly for the attack of a fortified area are the well suited to this task. Smoke isolates same as those for any other type of offensive individual strongpoints from the observed operation (FM 30-5). The collection plan is based on the essential elements of informa- fires of other fortifications. Indirect fire tion (EEI) and other intelligence require- weapons destroy camouflage, neutralize and ments established by the commander. Special destroy enemy field fortifications and artil- measures are taken to determine the following: lery, and screen the movement of assault (1) Exact location and extent of individual troops. If the fortified area is wooded, infil- fortifications. tration may be employed for the seizure of (2) Location and number of embrasures key command and communication bunkers. and fields of fire and types of weapons /. The assault elements are tailored to their therein. specific missions and should be specially (3) Location of all entrances and exits trained and rehearsed on replicas of the to emplacements. position. Their principal weapons are (4) Direction of fire from enemy fixed demolitions, flamethrowers, and direct fire weapons and types of weapons. weapons. (5) Extent of underground fortifications. g. Reserves follow(6) closelyLocation behind of all the natural as- and artificial sault echelon to exploit the penetration, obstacles. The defenses are care- maintain the continuity of the attack, or fully analyzed to detect any weak defend critical areas against counterattack. spots. 12 (7), Location and condition of reserves, Force aircraft and Army air vehicles in con- and reinforcements, including sup- junction with visual or electronic surveil- plies, weapons, ammunition, and lance techniques often discloses a road, trail, transportation. or emplacement where the camouflage has b. Army topographic engineer unitsbeen pre-destroyed or altered by the fire. pare large-scale maps of the fortified area. c. A reconnaissance-in-force may be used Available maps and intelligence must then to develop enemy information rapidly, and to be supplemented and updated to the extent discover, ascertain, and test the enemy’s that time, capabilities, and facilities will position and strength. Although its primary allow in order to provide required informa- aim is reconnaissance, the reconnaissance- tion of the terrain and the details of individ- in-force may discover weaknesses in the ual emplacements and weapons positions. enemy dispositions which, if promptly ex- Terrain models and sandtables should be ploited, may achieve tactical success. A prepared. Detailed and frequent airphoto battalion may conduct a reconnaissance-in- coverage is a major source of information. force for the brigade to which it is attached, Special photos are used to penetrate camou- or it may be committed to exploit enemy flage, while low oblique photos are used to weaknesses discovered by other reconnais: reveal vertical detail such as embrasures sanee elements. Elements of a battalion that may not be picked up by vertical photos. may also conduct a reconnaissance-in-force Open emplacements, obstacles, and newly on a limited scale. Armored formations are constructed log and earth bunkers are more ideally suited to a reconnaissance-in-force readily located than other fortifications. because of their mobility and firepower. Aerial surveillance by observation and pho- d. For considerations and conduct of recon- tography can identify current construction naissance operations, see FM 7-20 and FM and detect other activity. Additional de- 61-100. tailed information regarding construction 18. Communication and Coordination and plans of fortifications may be obtained The success of the detailed coordination from prisoners of war and from noncom- effort depends upon the effectiveness of the batants, some of whom may have been used communication system developed for the to construct fortifications. attack. Both wire and radio are used. Radio nets must be provided with common 17. Reconnaissance channels between attacking and supporting a. Ground and aerial reconnaissance are foi'ces. Prearranged visual signals, such as primary means of collecting information pyrotechnics, may be used to signal the cap- about a fortified area. Both are exploited ture of key bunkers or objectives. Emer- to provide detailed information such as the gency signals for lifting or shifting fires must location of local reserves, troop movements, be thoroughly understood by all subordinate artillery positions, self-propelled weapons, leaders. Positive arrangements must be actual and dummy emplacements, and cam- made to position and control all units of the ouflaged works. Reconnaissance should attacking echelon so that piecemeal assaults emphasize the need to discover the most ai’e prevented and simultaneous attacks are advantageous direction and routes of ma- assured against mutually supporting de- neuver of attack elements, and the best uses fenses throughout the entire operation. of direct fire support. Adjacent units must not arrive in attack b. Reconnaissance by direct and indirect positions and come under the defender’s fire is also an effective technique. Under fires separately. direct fire, haystacks and houses are often 19. Night Attacks revealed as camouflaged concrete emplace- Night attacks may be conducted to sur- ments. Caves and indentations in hillsides prise the defender and to avoid or reduce are reconnoitered by direct fire and may dis- losses which might be incurred by daylight close prepared positions. After an indirect attacks against fortified areas. Successful fire mission is completed in a particular night attack is especially dependent upon area, detailed aerial observation using Air detailed reconnaissance. Night attacks

13 normally are conducted to exploit successful bases for continuing the attack by day. daylight attacks, to gain important terrain, For additional information and details on or to seize key bunkers prior to daylight as battlefield illumination, se'e FM 61-100.

Section II. PLANNING 20. General 21. Scheme of Maneuver a. Plans for the attack of a fortified area, a. A plan for the attack of a fortified area to include the use of feints and ruses (FM is prepared in advance to permit subordi- 61-100), are more refined and are prepared nate units to be disposed correctly for move- in greater detail than plans for attacks ment to the area and to attack positions. against other defensive positions. Central- b. Planning and organization for the attack ized planning, which is characteristic of this continue after contact has been made and the type of operation, is normally conducted at fortified position is developed. Planning battalion and higher levels. Specific tasks includes the exploitation phase of the attack. and their sequence of accomplishment are While troops and materiel are being as- sembled and readied, commanders and staffs frequently assigned by battalion. At com- conduct detailed studies of maps, aerial pany and platoon level, detailed plans are photographs, and ground and aerial recon- prepared for the reduction of each bunker. naissance reports. Evaluated information Direct fire, crew-served weapons are assigned is disseminated to attacking units as intelli- specific embrasures and other detailed tar- gence. gets for neutralization. The detailed plans c. A passage of lines may be employed for should provide for continuation of the attack initiating the attack. This type of action through the entire depth of the fortified will afford the attacking units adequate time area and for reorganization on the far side for preparation and provide a covered posi- of it. Plans must provide for the possibility tion from which they can procure special of encountering previously undetected bunk- equipment, conduct rehearsals, ánd make final preparations for the attack. ers along the route to the objective and for neutralizing underground defenses encoun- 22. Formations tered. When nuclear or chemical weapons are employed to support the attack, alternate a. The necessity for heavy fighting through- plans must be prepared for execution in the out the depth of the fortified area usually event the desired results are not obtained. requires formations in greater depth than in normal offensive operations in order to For example, meteorological conditions may maintain the momentum of the attack. preclude the use of chemical fires at the This depth will be maintained at brigade desired time of attack. level. The number of companies in the b. Under nonnuclear conditions, the attack attacking echelon will depend upon the of a fortified area is slower, more deliberate, assigned frontages, anticipated enemy re- and more strictly controlled. A greater sistance, forces and fire support available, concentration of maneuver elements is and the nature of the fortified area. required to compensate for the absence of b. In assigning frontages, consideration nuclear fire support; frontages of attacking should be given to the density of bunkers units are narrower; objectives are shallower; to be attacked. Since the attack will con- and units normally are required to clear their stitute a series of platoon assaults, bat- talion and company commanders must assigned zones. Each bunker must be sys- consider the capabilities of the attacking tematically reduced by ground assault. Re- platoons. The primary restrictions on the serves may be committed more frequently number of bunkers assigned to a rifle pla- than in other types of operations. Since toon for reduction during a particular opera- slow, hard fighting is anticipated through- tion depend upon the following: out the depth of the fortified area, armored (1) Length of time a bunker must be and mechanized infantry exploitation forces guarded to prevent reoccupation by will probably not be committed until the the enemy. penetration is achieved. (2) Ability to resupply the unit. 14 (3) Availability of special equipment in 24. Frontages sufficient quantity to continue the Frontages for divisions attacking a forti- attack. fied area will normally be less than those (4) Ability of the organization to sustain employed in normal offensive operations, casualties and remain effective. with correspondingly reduced frontages for attacking brigades, battalions, and com- 23. Control Measures panies. The specific frontages will be deter- a. Control measures employed in the attack mined by the mission, enemy situation, num- of a fortified position are more restrictive ber of bunkers to be cleared, terrain, and than in less deliberate attacks, and nor- troops available. Other factors may include mally include a sequence for the reduction existing road nets, anticipated resistance, of known bunkers. Since seizure of the available fire support, and relative strength bunkers is necessary to clear the zone and and mobility of the attacking units. insure domination of the objective area, bunkers as well as terrain features are 25. Plan of Fire Support assigned to rifle companies as intermediate a. The detailed plan of supporting fires objectives. Terrain features are designated includes all weapons used to support the as company objectives to facilitate reorgani- attack. These may consist of ground and air zation and control, and defense of the bat- delivered nuclear fires, chemical and biologi- talion and brigade objectives. cal agents, and nonnuclear fires. (1) In a nonnuclear situation, the ob- (1) Scheduled nuclear fires are planned jectives initially are located within on forward defenses, on deeper posi- the nearest fortified belt or zone. Re- tions that may be reached early in serves may be required to seize the attack, and on reserves that offer terrain for continuation of the attack suitable targets. Airbursts are used against the next fortified belt. in the area of penetration to achieve (2) Nuclear fire support will permit an effective neutralization of fortifi- attack in greater depth because of cations when fallout is not desired. the destruction or neutralization of Surface burst weapons may be used many bunkers. The seizure of on the flanks of the penetration when deeper objectives may facilitate the launching of an attack against the the predicted fallout will not affect next fortified belt. operations of adjacent units and b. A sequence for the reduction of known when there is reasonable assurance bunkers is assigned to rifle companies to that elements of the attacking force insure that — will not require early use of the area. (2) On-call nuclear fires are planned on (1) Fortifications which are mutually intermediate and rear fortified belts supporting will be attacked simul- that are not expected to be reached taneously. early in the attack. Premature (2) Fortifications having fields of fire that nuclear attacks or rear fortified belts dominate antitank and other ob- may reveal the plan of maneuver stacles and routes are reduced as and permit the defender to react in quickly as possible. strength. Care must be taken, how- (3) Maximum mutual support between ever, to insure that the on-call fires attacking companies is maintained. are delivered early enough to prevent (4) Employment of supporting fires can • the attacking forces from losing be readily coordinated. momentum or from being unneces- sarily subjected to counterattacks (5) A maximum number of fortifications and deliberate defensive fires. can be attacked from the rear or from b. Nonnuclear fires are planned to supple- an undefended or “blind” side. ment nuclear fires. Primary tasks for the (6) The battalion zone is cleared to insure indirect fire weapons are as follows: that enemy troops or shelters are not (1) Prior to the nuclear preparation, to bypassed. destroy camouflage and mines.

15 (2) Following nuclear fires, to maintain good results when used extensively against neutralization of the defender in counterattacks, against personnel in open critical areas. emplacements, and in smoking selected en- (3) Interdiction of the movement of . emy positions. reserves. b. Davy Crockett. The Davy Crockett is (4) Counterbattery and countermortar normally employed in general support. fires. Primary targets are massed enemy per- sonnel. However, the weapon can be used (5) Close support of attacks on remaining effectively against mortar or artillery posi- defenses. tions, groups of vehicles, personnel who (6) Blinding defensive positions in depth occupy forward defensive and outpost posi- or on the flanks of the penetration tions, command posts, or logistical instal- with smoke, and increasing attacking lations. Generally, targets are selected formations. which are vulnerable to the effects of the c. Main guns on tanks, demolition guns on weapon, and whose destruction or neutrali- combat engineer vehicles, and antitank zation is critical to the commander’s plan weapons are used extensively to neutralize of attack. On occasion, the section or its and destroy bunkers. Medium and heavy individual squads may be employed in a artillery weapons may also be employed in a restricted form of direct support of a rifle direct fire role to accomplish these effects. company(ies). This restricted form is These weapons support the assault by deliv- applicable when using nuclear warheads. ering accurate direct fires into firing em- When employed in this manner, and in con- brasures of bunkers and weapon emplace- trast to the use of other weapons in a direct ments. Initially, the direct fire weapons are support mission, the Davy Crockett will be assigned specific embrasures and other fired only on approval of the battalion com- targets to neutralize; thereafter they are mander and is neither authorized nor re- employed as additional targets are located. quired to answer directly the supported unit’s requests for fire. However, displace- Smoke from direct and indirect fire weapons ment will be made by the section or squad can be used effectively to deny observation leader as required to meet the needs of the to the defender. Direct fires should be supported unit. Because of the importance planned in detail and closely coordinated. of the section to the battalion as a whole, d. A preparatory air bombardment is not the battalion commander will normally usually employed when a nuclear prepara- require the rifle company being directly tion is used. Following the , nuclear pre- supported to provide adequate close-in paration, close air support is used primarily protection of the Davy Crockett element(s). to locate and destroy reinforcements, dis- c. Artillery. Artillery indirect or direct rupt counterattacks, and attack individual fire may be used in conjunction with other bunkers that are difficult to engage by other direct fire to neutralize or destroy enemy means. Air alert aircraft are desirable to fortifications. Self-propelled medium and insure rapid action against any threats. heavy artillery are most effective for this e. As in other offensive operations, the purpose. These weapons support the assault fire support plan is closely related to the by delivering extremely accurate fires into scheme of maneuver. Fires are planned to embrasures or weapons emplacements, and destroy or neutralize known or suspected by destroying walls or bunkers. For ex- ample, the concrete-piercing rounds of the targets and to support the maneuver of the 155-mm and 8-inch howitzers, respectively, attacking echelon. In addition, fires will be can penetrate 91.44 centimeters (one yard) planned to protect the reorganization and and 142.24 centimeters of concrete at a consolidation in the objective area. range of 2,700 meters. d. Antitank Weapons. The fires of recoil- 26. Employment of Supporting Weapons less rifles, antitank rockets, and antitank a. Mortars. Theguided 81-mm missiles and 4'2-inchare' integrated mor- .into the fire tars are normally employed in general support plan tö ässist tanks and artillery in support. Although mortar fires are gen- the neutralization of bunkers during the erally ineffective against well-constructed assault. The battalion antitank platoon is and permanent fortifications, they provide usually retained under battalion control 16 for greater flexibility in engaging stubborn integrated into the company fire and previously undetected weapons, and plan. Provision may be made for the against counterattacks. Squads of the tanks to be further attached to rifle platoon may also be attached to rifle com- platoons for continuation of the panies-when an armor threat can be antici- attack after obstacles have been pated, when the terrain restricts maneuver breached. of the antitank weapons, or when the fires (2) The dozers may be used to assist can be more readily controlled through attachment. The 106-mm recoilless rifle in reducing obstacles, especially in is highly effective as a bunker assault weapon the initial phase of the attack. As because of its accuracy in firing shells into soon as assault elements close on stepped embrasures. each fortification, the tank dozers e. Tanks. Tank-infantry-engineer task are moved forward to be available to forces are usually formed for the attack of a cover fortification openings with fortified area. A platoon or more of tanks dirt. This is an effective way to im- may be attached to attacking rifle companies. mobilize enemy troops who refuse to All tanks support the attack by firing at the surrender. embrasures of specified bunkers in pre- /. Flamethrowers. Both portable and mechanized flamethrowers may be'used to scribed sequence. Once,slth,e> antitank ob- stacles have been breached, those tanks support the assault, teams by reducing forti- attached to the attacking echelon follow fications and providing close-in protection; quickly and join in the continuation of the they may also be used for mopping-up tasks attack. Tanks remaining under battalion after fortifications have been breached control may provide additional fire support (figs. 6 and 7). Because of their limited from hull-defilade positions, br may be as- range, mechanized as well as portable signed to the reserve for antitank protection flamethrowers operate in the same location to the flanks and rear. For details of em- with the attacking elements; they are usually ployment, see FM 17-1. attached to attacking rifle companies. The (1) When attached to rifle companies, division support command "or supporting tanks are initially retained under Chemical Corps units provided by corps or company control and their fires are army will assist in the loading of flame-

3. ^

NJ*

at»',m m ÜSt 'h. mi * I# wm ¡Ví IlliSiSlIil rdí m Figure 6. Portable flamethrowers in action.

719-500 0-64-3 17 m

mm-®» ,,, ■' J J *■ m,

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Figure 7. MIO flame unit firing from an Ml 13 armored -personnel carrier. throwers. Although it is difficult to pinpoint (2) To exploit the destructive effects targets for flamethrowers at night, use of of nuclear weapons, it is usually flame weapons at night should nevertheless desirable to follow their employment be considered for their psychological as immediately with a ground attack. well as destructive effect on the enemy Airburst avoids extensive radiologi- (FM 7-10). cal contamination of the area of operations. Low airbursts may be g. Nuclear Weapons. Nuclear weapons more effective against well-con- may be employed to create gaps or isolate structed fortifications, but may sections of fortified areas. Depending on produce tactically significant induced the predicted nuclear effects, the number radiation in the vicinity of ground of units in the attacking echelon may be zero. Collateral effects such as fires; reduced, deeper objectives may be assigned, reduced visibility, from smoke and and fortifications may be attacked and dust; blowdown; and displaced rub- destroyed more rapidly when nuclear weap- ons are used. ble and debris may prevent immedi- ate exploitation. Well-constructed (1) The effects of radiological contami- fortifications are relatively less nation will require evaluation of vulnerable to airburst nuclear possible interference with the opera- weapons; thus surface bursts may be tions of friendly maneuver elements required to achieve the desired level and careful coordination with ad- of destruction. jacent forces. Disposition of for- ward forces may have to be adjusted h. Smoke. Smoke delivered by artillery for troop safety prior to the use of and mortars, or by chemical smoke gen- nuclear weapons. erator units, may be used as a screen to 18 cover the movement of troops; to screen one HD or VX) can be used against enemy strong- or both flanks of a gap, such as might be points that are bypassed and need not be created by unequal advance of units; to occupied immediately by friendly forces. screen an. area outside of the immediate action; or to blind observation posts and fortifications that cannot be neutralized 27. Engineers by other weapons. Even if the attack is During preparation for an attack, engi- made during darkness, smoke may be neers conduct thorough technical recon- valuable to counter enemy use of illuminat- naissance to determine types and depth of ing flares and night vision devices and enemy obstacles and minefields and recom- shells. The use of smoke must be coordi- mend the locations where enemy barriers nated to insure that it will not interfere will be breached. They assist in preparing with direct fires on fortifications or with demolitions and in training infantry units ground observation by the attacking echelon. in the use of explosives. Priority engi- If wind conditions are favorable, every neer tasks during an attack include assisting effort must be made to blind fortifications in the breaching of obstacles, destroying that can support those being attacked. captured bunkers, and maintaining or pre- i. Toxic Chemical Agents. Nonpersistent paring routes of advance for combat vehicles. chemical agents (examples: GB from burst- The demolition guns of combat engineer ing-type munitions near the target and CS vehicles (fig. 8) may be effective for neutral- from M4 dispensers) will project a portion ization or reduction of enemy installations of the toxic cloud into the fortifications. and fortifications. Combat engineer vehi- Direct hits are not required. Individual cles may be assigned to attack enemy targets fortifications may be attacked as point which otherwise would require the use of targets, or nonpersistent chemical agents infantry-engineer assault troops on foot. may be used on the entire fortified area. Tank dozers may also be used in lieu of Persistent chemical agents (for example, combat engineer vehicles.

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Figure 8. Combat engineer vehicle. 19 Section III. CONDUCT OF THE ATTACK 28. General reconnaissance and security echelons in a. battalion and higher levels, there is front of the fortified area. no major difference between the execution of b. The attack of the area usually begins an attack against a fortified area and against with an intense air and artillery prepara- normal defensive positions. Some of the tion and, if wind conditions are favorable, variations employed in the former include the laying of a smoke screen. During such more frequent “leapfrogging” of subordinate preparation, routes are cleared of mines and units to maintain the momentum of the obstacles to assure unimpeded progress of attack and closer control of subordinate units the attacking echelon. to insure that the highly detailed and coordi- c. When routes have been cleared, the as- nated plans are properly executed. sault elements advance as rapidly as pos- b. At company and platoon level, attacks sible under the cover of all available against bunkers are conducted by fire and supporting weapons. Direct fire weapons maneuver. The method of attack against an engage embrasures and other openings in the unexpectedly encountered bunker is the fortifications. If the fortification is pro- same as it is against a bunker located and tected by wire obstacles, paths are cleared by assigned during advance planning. A por- wire-cutting parties, tanks, or bangalore tor- tion of the force executes the maneuver pedoes. When a route has been cleared, the while another portion acts as the fire support assault groups attack, employing flame and element. The fire support element neu- demolitions, to knock out the enemy bunkers tralizes known or suspected enemy bunkers and kill or capture defenders in open ter- and other emplacements from which fires rain (figs. 6 and 7, and par. 236). Close sup- may hinder the maneuver; it may also deline- porting fires are directed toward getting the ate objectives and strongpoints by fire to assault groups into positions from which assist supporting weapons in locating suit- they can knock out assigned bunkers. These able targets. The maneuver element ad- groups approach the bunkers from the blind vances under the cover of supporting fires side whenever possible. Fires are continued to a position from which it can destroy the as long as troop safety will permit. Indirect enemy with grenades, explosives, and an fires and tank gun fires are normally shifted assault. The assault may be supported by on orders of the rifle company commander. special (or additional) equipment not nor- Machineguns — both tank and ground mally carried by platoons or squads. This mounted —and other direct fire weapons lift equipment may include flamethrowers, demo- or shift their fires when masked, after which litions (pole, satchel, or shaped charges), and they resume firing on order of the assault bangalore torpedoes. rifle platoon leader or the weapon com- c. If nuclear weapons are employed to sup- 1 mander. Fires of the attacking platoons are port the attack, their effects are exploited usually the last fires lifted. Prearranged rapidly by having dismounted or mounted visual signals (e.g., pyrotechnics) are used as assault troops knock out remaining defenses required by the maneuver element com- and hold open the gap. Armored and mecha- mander to shift supporting fires. nized infantry forces, assisted by engineers, d. Upon breaching the fortification, the follow closely and pass through to deepen the assault group seizes the emplacement and, penetration. A mounted attack against the using grenades and portable flamethrowers, initial defenses of a fortified area is usually overcomes all resistance. Flank security not practical because of numerous antitank and reserve forces move up and cover the obstacles which impede vehicular movement. reorganization of the attacking echelon. The attacking platoon consolidates the 29. Conduct of the Attack bunker area and takes the necessary steps a. The initial objectiveto prevent of thecaptured attacking bunkers from being force is the destruction and removal of enemy reoccupied by the enemy. Elements of the 20 company or battalion reserves may relieve the defender with flame or grenades the assault platoon of this responsibility. so that demolitions can be placed in e. During the mop-up of the area, tanks the embrasures and detonated. are ready to fire on probable avenues of (3) Equipment should be so distributed enemy counterattack. Tanks that have that casualties will not cause the been supporting the attack by fires are attacking force to lose the means of moved forward to assist in this. The pla- reducing the bunker under attack. toons (or newly designated assault forces) This can be accomplished by employ- continue the attack without delay to deepen ing two of each item of special equip- and widen the breach and complete the de- ment and assigning each item to a struction of the fortified area. Mechanized separate individual. and armored units may be committed upon c. Task No. 3. penetration of the enemy’s first defensive (1) Assault and kill or capture the enemy belt with the mission of seizing initially in open emplacements in the vicinity the terrain between the first and second of the bunker. defensive belts and subsequently the second (2) Task No. 3 is accomplished by a rifle defensive belt. squad or squads of the maneuver force. During the movement to the 30. Conduct of the Platoon Attack final coordination line, and during The method employed by an attacking pla- the execution of task No. 2, rifle toon to close with and destroy an enemy squads protect personnel assigned position or bunker evolves from three prin- to carry special equipment. On cipal tasks: order it assaults the objective, killing or capturing the enemy in the vi- a. Task No. 1. cinity of the bunker. (1) Fire into adjacent areas, engaging previously undisclosed enemy posi- d. The three tasks may be accomplished tions which threaten the maneuver. by organizing the available force into three The purpose of this task is to aug- elements, or one element may be required ment fires of the fire support ele- to perform more than one task. For ex- ments and to neutralize enemy fire ample, personnel armed with the automatic in the vicinity of the objective. rifle may be required to perform task No. 1 (2) Fire on enemy positions outside the initially and then take part in the execution bunker which threaten the maneuver of task No. 3. Riflemen, whose primary mis- of the assaulting force. This is sion is the accomplishment of task No. 3, usually accomplished by that portion also assist in augmenting the fires of the of the maneuver element not en- element executing task No. 1; and certain gaged in neutralizing the bunker. riflemen will be prepared to take over special b. Task No. 2. equipment from personnel who become (1) Destroy or reduce to ineffectiveness casualties while executing task No. 2. the bunker under assault. The e. A typical organization of an attacking method in this task is to neutralize rifle platoon may be as follows: the bunker with” grenades, demoli- FIRE SUPPORT ELEMENT tions, or flame and secure it until Platoon Sgt additional troops arrive to occupy or destroy the bunker. Weapons Sqd (-) MANEUVER ELEMENT (2) Task No. 2 is accomplished by a part Task No. 1: of the maneuver element employing 1st Rifle Sqd organic arms and equipment or by 90-mm Recoilless Rifle Team 1 personnel who have been issued special equipment. Normally, this

group moves to the bunker under ‘Weapons squad crew-served weapons are attached to the rifle the cover of supporting fire and stuns squads as the situation demands. 21 Task No. 2: enemy fire, assaulting the enemy in 2d Rifle Sqd organized as follows: open positions in the vicinity of the TEAM ALFA bunker, and seizing the bunker from Sqd Ldr2 the flank or rear. This method may 1 Team Ldr be used against a bunker whose fires 1 AR Man can be neutralized to the extent that 2 Men3 the surrounding trenches and fox- TEAM BRAVO holes can be successfully assaulted. 1 Team Ldr (2) Execute task No. 1, followed by task 2 Flame Gunners No. 2, then task No. 3. In this meth- 2 Demolitions Men od, the attack is conducted by neutral- Task No. 3: izing the enemy fire, assaultingrthec. 3d Rifle Sqd bunker, and then assaulting the Platoon Hq enemy in open positions in thet Platoon Ldr4 vicinity of the bunker. This method Radio-telephone Operator is often forced upon the attacker 31. Sequence of Accomplishment of the because the bunker covers the only logical avenue of approach. Three Tasks b. To insure the success of an attack a. The three tasks are not necessarily against any specific bunker, fires from all executed in numerical order. Variations in supporting enemy bunkers must be neutral- the method of seizing a bunker are as follows: ized as quickly as their positions become (1) Execute task No. 1 followed by task known. When possible, mutually supporting No. 3, then task No. 2. The attack emplacements are attacked simultaneously. may be conducted by neutralizing Once an entry is made into a fortified area, there will be an opportunity to assault ¿ May be with either team. 1 Grenadiers can accomplish this mission, then support. other emplacements from the flank or rear 4 The platoon leader locates himself where he can best control the attack. until the entire system is reduced.

22 CHAPTER 4 DEFENSE OF A FORTIFIED AREA

Section I. General 32. General releases proportionately larger forces a. The primary purpose of a fortified area for reserves. is to increase the natural defensive strength (2) Reserves must have suitable mobility of the terrain. It includes the use of towns and be used aggressively if the as anchors of the fortified area. This should defense is to be successful. cause the enemy to mass and present a profit- (3) Fortifications are organized in depth able target in committing sizeable forces and to provide all-around defense. Field effort in the reduction of the fortified area. fortifications supplement the bunk- He thereby expends his combat power and ers, pillboxes, and other fortified leaves himself vulnerable to counterattack. works. b. The fortified area may be prepared (4) The fortified area provides excellent deliberately prior to the commencement of protection for the defender and in- hostilities, or it may be developed under cover creases the effectiveness of his fires. of forward defensive forces during battle. (5) The defense is conducted in the same It may also be developed as a result of con- manner as an area defense. De- tinued occupation and improvement of for- fense of a fortified area is not nor- ward defensive positions during periods of mally associated with the mobile enemy inactivity or stalemate. In either defense. case, the fortified area is normally planned c. Obstacles are an integral part of every in detail and improved continuously. permanent defensive installation. They are emplaced in depth and constructed in such a 33. Defensive Considerations manner as to force the attacker to breach a. Any fixed defense, no matter how elab- them in order to reach key points held by the orate and well planned, can be penetrated defender. Natural obstacles are reinforced if sufficient means are used by the attacker. by a system of well-camouflaged concrete Although the defender may have a great and steel, or log and timber structures, with deal more protection from fires, the attacker weapons and apertures emplaced to cover the can choose his point of. attack and concen- barriers by fire. Antitank and antiperson- trate his efforts on the fixed defender at nel minefields; flame field expedients such as that point, either destroying the defender fougasse; toxic chemical agents; wire en- or causing him to relinquish his chosen tanglements; antitank ditches; and log, post, position. The defense must, therefore, pro- and concrete antitank obstacles are organ- vide offensive means by which an attacker ized into a system of barriers-in-depth to can be destroyed once he penetrates the force the attacker to commit his strength defended area. against the obstacles. A deliberately b. Specific considerations in the defense planned fortified area makes the widest pos- of a fortified area include the following: sible use of barriers in defensive operations. (1) Fortified areas Forpermit details economy-of- and illustrations, see paragraphs -r force in forward defense areas. This 6 through 11.

23 34. Defense ¡n Nuclear Warfare b. On-call nuclear fires may be planned by a. It is almost impossible to conceal an the defender on likely enemy assembly areas and avenues of approach. Because the de- extensive fortified area for any extended fender has a degree of protection from nu- period of time. By diligent . intelligence clear weapons effects in his fortified posi- efforts, an accurate picture of the fixed de- tions, nuclear fires may be planned closer fenses can be developed. Although they to the defenses than in other i situations. provide a degree of protection, fortified areas Counterattack plans also include' the use of can be destroyed by nuclear weapons. nuclear fires.

Section II. PLANNING 35. Organization of the Battle Area support by adjacent units and weapons is mandatory. a. The forward edge of the battle area (3) Reserves should be highly mobile (FEBA) is organized as a fortified belt con- and located well back to destroy and sisting of a number of mutually supporting eject enemy penetrations into the defense areas, or strongpoints, disposed fortified area. Ideally, the depth irregularly in width and depth. Each strong- of the fortified area should be suffi- point is organized for all-around defense cient to force the enemy artillery to with bunkers, trenches, foxholes, weapons displace forward during the attack. emplacements, observation posts, connecting This reduces surprise effect and gains caves or tunnels, shelters, and obstacles. time for the reserves in the launch- Tactical unity and integrity are maintained ing of a counterattack. in each defensive area or strongpoint. Each defensive area or strongpoint is capable of b. Forward brigades organize and defend supporting adjacent units by fire. Strongs -■ -the first fortified belt. Second and suc- point locations are selected for the observa- ceeding fortified belts are organized and tion and fields of fire they afford and for their prepared for the defense by reserve brigades natural defensive strength. Their reteq-^ and reserves of higher commanders. Se- tion insures the integrity of the battle area. curity, forward defense, and reserve areas are organized as in an area defense. (1) A fortified belt is sited to take full (1) The capability of the general outpost advantage of the terrain. The weak- and the combat outpost to delay the est terrain should be organized in enemy is increased considerably by greatest depth and defended by the prepared fortifications in those areas. strongest and most numerous de- Strongpoints are prepared to cover fensive works. natural and artificial obstacles (2) As in hasty defense, interlocking which cause the enemy to deploy prematurely and launch coordinated bands of grazing machinegun fires attacks against lightly held for- form the backbone of defense in ward security positions. Similar a fortified belt. Weapon positions use is also made of suitable delaying are protected from-the front by ter- rain irregularities, and grazing fires positions between the general out- post line (GOPL), combat outpost . are directed to the flank across LINE (COPL), and the FEBA to likely routes of attacking forces. No terrain should be left entirely with- achieve further delay. out protection by fire. A combina- (2) Rifle companies of forward battalions tion of interlocking bands of grazing occupy bunkers and emplacements fire, with high angle fires filling in in the forward defense area. They the dead space, are essential to stop prepare and improve fields of fire, or repel enemy assaults. Mutual integrate their fires to cover the 24 entire area forward of the FEBA, 36. Fire Support. Planning and cover obstacles with antitank The fire support plan for defense of forti- ..and other fires. Additional antitank fied areas is prepared as for other defenses; weapons may be provided from the specific emphasis, however, is placed on the battalion antitank platoon. Some coordination of fires with the barrier plan. elements of the forward rifle com- When nuclear fires are used, they may domi- panies may be disposed to fight from nate the defensive fire plan. Nonnuclear open emplacements to provide fires are planned to assist in the defense of close-in protection to certain rela- fortified positions, to assist in causing the tively “blind” bunkers. It is im- enemy to mass his forces, to augment the portant that they cover by fire all effects of nuclear fires, and to cover areas entrances to bunkers. During artil- where nuclear fires are not used. To the lery and air attack, personnel as- extent possible, areas most critical to the signed to open emplacements may success of the enemy attack are planned as move to nearby covered shelters and on-call nuclear targets. These areas include return to their fighting positions locations where enemy forces may be ex- after the fires lift. pected to concentrate; e.g., at obstacles, attack positions, assembly areas, and defiles. (3) Reserve rifle companies of forward battalions may be located in con- a. Antitank fires are planned to engage cealed assembly areas or under- enemy armor as soon as it comes within ground shelters and be prepared to effective range.- The battalion antitank move quickly for participation in platoon may be retained under battalion counterattacks. They make maxi- control to add depth to the antitank defense, mum use of concealed or under- or squads may be attached to forward rifle v ground routes when moving to the companies which cover enemy armor ap- line of departure. Reserve rifle proaches. Company antitank weapons are companies must also be prepared to under the control of the company commander. occupy previously prepared block- They may either be retained in central lo- ing positions to limit penetrations, cations for movement to firing positions when prevent envelopments, or defend armor threats arise, or sited within the defensive position and their fires coordi- against enemy airborne infiltra- nated with the other antitank weapons for tions and guerilla attacks. employment against tanks and assault guns. (4) Obstacles forward of the FEBA must Platoon antitank weapons are normally lo- be planned to permit efficient with- cated in open emplacements for employment drawal of security forces through in antitank and antipersonnel roles. Com- gaps, and to canalize the enemy into pany and higher unit antitank weapons are areas of intense defensive fires. not normally employed in an anti-personnel Obstacles within the battle area role. must be sited to impede enemy move- ment but allow free movement of b. Tanks are normally a part of the reserve friendly reserves to counterattack for employment in counter-attacks. How- or occupy blocking positions. Port- ever, when numerous armor approaches able obstacles are also prepared for exist, some of the available tanks may be attached to forward rifle companies to cover closure of gaps in the barrier system critical avenues of approach from dug-in within the battle area. Extensive positions. use is made of protective wire to prevent assault parties from closing 37. Communications on bunkers. Tripwires may be in- V stalled across natural avenues of Permanent fortifications, and to a lesser approach to actuate devices to give extent field fortifications, have dependable an alarm (pars. 8-11). wire communication systems that reduce the

719-500 0-64-4 25 need for radio. This assures greater com- may contain radar and television trans- munication security and reliability. Com- mitters. Tactical deception operations may munication wire is buried deep enough to ‘ be conducted utilizing communication minimize damage from nuclear and non- equipment, radio nets, and other electronic nuclear explosive fires and bombing. Alter- means. . Installations within an area are nate lines . are installed. Interconnecting trenches and underground passageways provided with intercommunication systems. between individual bunkers provide covered Radio supplements . the wire system. For routes for messengers. Command posts additional information on communication, may be equipped with teletypewriter and see FM’s of the 7- and 17-series and FM television equipment; observation posts 61-100.

Section III. CONDUCT OF THE DEFENSE

38. General Obstacles cause the enemy to mass or deploy prematurely; direct and indirect fires are The conduct of the defense of a fortified employed to inflict ' casualties. If enemy area is similar to that for a normal area tanks are employed, all available fires are defense. See FM’s 7-11, 7-15, 7-20, 7-30, delivered to force tanks to button up, and and 61-100 for details. ^ to separate infantry from tank elements, thereby facilitating their destruction. Nu- 39. Conduct of the Defense clear weapons may be used as appropriate, a. Unless deception is an essential element and antitank mines and available tactical of the defense, the enemy is taken under air support are used to the maximum. . Artil- long range fire —including nuclear fires and lery and mortar fii’es, to include chemical toxic chemical agents (if appropriate) —as agents, may be used on tanks and other early as possible. Tactical air support is weapons to blind or destroy the crews and used to locate and warn of the enemy’s ap- destroy accompanying infantry. Special proach, to interfere with his advance, and to efforts are made early to locate and destroy engage him well forward of the fortified area. enemy demolitions and flamethrower teams. Actions taken by covering forces and general If the enemy succeeds in launching an as- and combat outposts are similar to those for sault, final protective fires and all other the area defense. available fires are placed on him. b. After accomplishing their missions, or c. If the enemy penetrates the battle area, when necessary to prevent their capture or mobile reserves counterattack to destroy destruction, security forces withdraw through him and to recapture specific bunkers. forward elements to the rear, fighting a Blocking positions are not normally required delaying action to inflict maximum casual- since bunker defense-in-depth accomplishes ties on the enemy. Long range fires are this purpose. Counterattacks are infre- placed on the enemy to cover the withdrawal. quently conducted at company level.

26 PART TWO COMBAT IN BUILT-UP AREAS

CHAPTER 5 GENERAL

40. Definitions 41. Tactical Considerations a. A built-up area is any group of build- a. Built-up areas may become battle areas ings designed for habitation or commercial because their locations control routes of purposes, such as a village, town, or city. movement or because they contain valuable b. Block-type construction is that type con- industrial or political installations. If any struction in which few or no gaps exist enemy in a built-up area chooses to defend-in- between buildings; e.g., business districts of force, it may be preferable to bypass or de- large towns or cities. stroy the area rather than become engaged in the time-consuming and tedious task of c. Detached-or semidetached-building areas seizing it from him. Such an attack might are areas of towns or cities in which the build- expose the attacker to the risk of having a ings are spaced relatively close together; e.g., large part of his force-destroyed by nuclear, residential areas with a high density of in- chemical, or biological weapons. If, how- dividual and duplex buildings. ever, the built-up area is critical to the at- d. Isolated housing areas include villages, tacker, the commander may be required to hamlets, suburban houses, or other small accept this risk. clusters of buildings which are surrounded b. Buildings in a built-up area interfere by large, open areas. with radio communications. Thus wire e. Critical areas are those areas in a built- communications and foot messengers fre- up area that may require special coordination quently will be the only effective means of and effort to overcome. Open areas between communications. buildings, superhighways, avenues, rail- c. Because of the restrictions on communi- roads, and other terrain features which pro- cations and observation, control is difficult vide the enemy an advantage in observation and is normally decentralized. and fire may become critical areas. Build- d. Direct fire weapons, which must be well ings bordering these terrain features are in- forward, are more frequently attached to cluded in the critical area. companies and platoons than in other /. A key building is a structure which con- operations. tains an important governmental agency or e. The decisions and initiative of small public utility or is one of distinct cultural, unit leaders assume added importance. political, or historical value. City halls, /. Sound, magnified and echoed between telephone exchanges, telegraph offices, closely spaced buildings, makes it difficult to waterworks, transportation facilities, hos- locate enemy weapons. Dust caused by the pitals, museums, and cathedrals are ex- impact of projectiles and by explosive amples of key buildings. Plans for seizure charges, together with the smoke from fires, of such buildings should provide for mini- adds to the difficulty of observation and loca- mum damage to the facilities housed therein. tion of hostile weapons.

27 g. The nature of combat in built-up areas b. Military Aspects of the Terrain in Built- may vary, based on the type of construction up Areas. and the location of buildings? (1) Observation and fire. Observation (1) On the outskirts of built-up areas or and fields of fire are restricted to the cities, isolated houses or small groups narrow lanes provided by streets and of houses are found surrounded by alleys. Observation is further re- small plots of land, gardens, farms, stricted by the use of smoke, and by fields, or vacant lots. When this dust and smoke created during the part of the city is attacked, the fighting. Because of these restric- houses should be treated as inferior tions, increased importance is placed pillboxes or individual emplacements, on seizing and securing the taller and the plan of attack may be no buildings and structures for use as different from that used over normal observation posts. The rubble and terrain where an occasional forti- debris created by destruction of ' fication is encountered. buildings will severely restrict exist- ' (2) In the residential district, buildings ing fields of fire and increase the vul- are more closely spaced and are usu- nerability of tanks and other vehicles ally flanked by streets on one side to ambush. and by gardens or grassy plots on the (2) Concealment and cover. Built-up other. The general layout may or areas offer excellent concealment and may not follow some geometrical cover for both the attacker ánd de- pattern. The type of attack to be fender. But the defender has an im- * used in this area may vary and will portant advantage in that the depend upon the density of the build- attacker must expose himself to ings. A modified form of street move through Ahe built-up area. fighting probably will be used, but The defender can increase his ad- basic offensive techniques generally vantage when he can select defen- will remain the same. sive positions in well-constructed (3) The center of the built-up area usu- buildings with good fields of fire. ally is the business section and it The effectiveness of the cover de- normally will consist of buildings of pends upon both the density of the block-type construction with little or buildings and the nature of their no space between buildings, except construction. Buildings constructed for an occasional park, street, or of flammable materials are easily alley. This type of construction will burned and may prove to be traps for require fighting from building to troops using them. Stone or ma- building and block to block. sonry buildings with thick walls h. Under certain conditions, psychological offer excellent cover even when warfare can contribute significantly to the bombardment has reduced them accomplishment of the mission (FM 33-5). to rubble. Buildings with basements or two or more stories offer good 42. Intelligence overhead cover. a. Planning. Difficulties of control inher- ent to operations in built-up areas can be (3) Obstacles. Buildings set close to- partially offset by detailed planning. Such gether in geometric patterns present plans require detailed information concern- obstacles to both men and vehicles. ing the enemy and his defenses, a layout of This is particularly true in areas of the built-up area, and information on the block-typé construction. Streets are nature of the surrounding terrain. These relatively easy to barricade and plans should be based on the most current cover with fire, thereby adding and complete intelligence available. Pro- effectiveness to the obstacles duction of the required intelligence follows Rubble can be used to construct ob- the procedures discussed in FM 30-5. stacles. Obstacles may be created 28 through the use of air, artillery, war, civilians, police, and utilities direct fire weapons, and explosives. employees concerning unusual fea- (4) Key terrain. Key terrain in built-up tures of the area such as the layout areas includes strongly constructed of sewers and underground conduits, buildings, or groups of buildings, and vantage points for observation. which cover, good avenues of ap- d. Reconnaissance. proach; bridges; and hubs of under- (1) All forms of reconnaissance are ground sewage and subway systems. exploited to secure information (5) Avenues of approach. Often the best required by commanders. Air recon- avenue of approach, in terms of con- naissance begins early in the plan- cealment and cbyer, is through exist- ning to determine the enemy’s ing buildings. Other avenues of location, disposition, and activity. approach are restricted to streets, Maximum use of aerial photography alleys, and underground sewage and is made to detect subsequent changes subway systems: in the enemy situation. This recon- (6) Movement. In areas of block-type naissance is conducted by both Air construction, movement is difficult Force and Army aircraft, and is con- for both men and vehicles. Streets tinued during the operation in the and alleys invite movement but con- built-up area. stitute readymade fire lanes and (2) Ground reconnaissance is initiated as killing zones. For this reason, dis- soon as practicable after receipt of mounted troops frequently are forced orders directing operations in the to breach walls, move through built-up area. The enemy’s battle buildings, or move through open position and activity are kept under areas under the cover of smoke or constant visual and electronic sur- darkness. Underground sewage sys- veillance. Patrolling is conducted at tems, subways, or multistoried all echelons and coordinated to deter- buildings may permit limited move- mine the location of enemy strong- ment either below or above ground points, obstacles, weapons positions, level. Vehicles are restricted to and reserves. movement through streets and alleys where they are subject to 43. Fire Support ambush. a. Poor observation, with its resulting c. Sources of Information. limitations on adjustment of fire, and the (1) United States produced or captured proximity of friendly and enemy forces in city maps, large-scale topographic contact make close support by artillery and maps, city pians, SLanuai'Q travel tactical air difficult. High angle-of-fire booklets, and related intelligence weapons, such as mortars, may be able to materials of varied scope and detail place fires into the area of defilade between are normally available from intelli- buildings. Delay fuzes may be used more gence and engineer sources. This frequently to permit projectiles to penetrate material, supplemented by recent roofs and upper floors before exploding. aerial photography and other com- Mortar smoke rounds fired in conjunction bat intelligence sources, should pro- with high explosive rounds have an adverse vide the required information on psychological effect on enemy personnel, and terrain, types of building construc- if there is sufficient litter, refuse, or rubble, tion, transportation facilities, pub- they can cause fires. Direct fire weapons lic facilities, and other important normally provide the bulk of close fire support. features. b. If nuclear fires are planned, their effec- (2) The intelligence officer should be tiveness may be increased by utilizing chem- alert to gain information, before and ical or biological weapons on the periphery of during the attack, from prisoners of the target after the nuclear burst. Chemical

29 and biological weapons should not be used defended buildings. These patrols can learn before the nuclear detonation except when the location of enemy weapons, reserves, and the agent characteristics, such as incubation obstacles; place explosive charges; and elimi- time, delay in casualty production, or delivery nate enemy positions. While large-scale means, so dictate. night operations are avoided, small, local night attacks may be used to position troops c. Limitations may be imposed on the use for daylight operations, secure buildings or of nuclear weapons because of casualties areas required for continued offensive opera- which would be inflicted on civilian popula- tions, and eliminate enemy strongpoints. tions, especially in friendly territory. In such The psychological effect of noise and fire at situations, incapacitating chemical and bio- night should also be considered. logical agents are ideally suited for integra- tion with conventional fire support. The 46. Looting limitations of these weapons systems must Built-up areas present many opportunities also be carefully considered. Biological for looting. As men acquire loot, they dis- weapons present the greatest limitations be- card needed equipment which results in an cause of friendly troop safety considerations overall loss of combat efficiency. No matter and the delay in casualty production. how well-trained or well-disciplined a unit d. Frequently, built-up areas will contain may be, troops will loot unless precautions installations and facilities —such as power are taken in advance. Looting detracts and water stations, railroad yards, and key from the soldier’s alertness, increases his buildings —which must remain intact, if pos- vulnerability and that of his unit, reduces his sible, for subsequent use by the friendly initiative and efficiency, and may delay the forces and the civilian population. Plans progress of the attack. Looting also alienates must be made to protect these installations the population. All leaders must insure that from friendly fire and to prevent the enemy orders against looting are obeyed and that from destroying them. Plans must also be violators are promptly and appropriately made to destroy designated facilities prior to punished. enemy capture. 47. Control of Civilians e. The use of portable or mechanized flame- a. The problem of controlling and admin- throwers or other incendiaries may be the istering civilians usually accompanies fight- quickest and most economical method of ing in built-up areas. A population swollen dislodging a defender from a building. How- by refugees will further complicate the prob- ever, the attacker must use these weapons lem. In friendly territory, cooperation can carefully, considering the possibility of creat- be expected from the local civil authorities. ing obstacles to his own advance or hindering In enemy territory, both friendly and hostile the maneuver of higher or adjacent units. elements may be present. Friendly local authorities should be used to control the civil- 44. Security ian population whenever possible. Circula- tion and movement of noncombatants is Basements, underground passages, and restricted and is regulated. The decision to upper floors create a requirement for security evacuate civilians from a built-up area is above and below, as well as to the front, normally made at the highest command level, flanks, and rear. The attacker frequently since refugee traffic within the battle area attempts to enter buildings from upper floors may interfere with the operations of other and roofs while the defender makes every friendly units. Loudspeakers and leaflets effort to guard these approaches. can be used to facilitate issuance of orders 45. Night Operations and instructions necessary for control of the Movement outside of buildings during day- civilian population. Psychological warfare light is greatly restricted; therefore, much of equipment and trained personnel to operate the fighting in built-up areas will take place it are available upon request from supporting at night. Under cover of darkness, streets psychological warfare units. Civilians may can be crossed more safely and small parties be used in the preparation of defensive posi- can infiltrate between defended areas or tions and other labor projects. 30 b. A civil affairs group composed of various combat operations. Where friendly or effec- civil affairs teams, depending upon the size of tive local government organization exists, it the built-up area, may be assigned or attached is used to assist civil affairs units. Assign- to a unit to administer the built-up area until ment to units normally ceases upon clearance a fully effective type of civil government can of the area, after which the group normally be reestablished. Without such support, comes under the control of a higher head- units will not be able to handle the civil prob- quarters. See FM 41-5 and FM 41-10 for lems and at the same time effectively conduct detailed procedures.

31 CHAPTER 6 ATTACK OF A BUILT-UP AREA

n Section I. GENERAL

48. General undertake a systematic clearance of the The ultimate mission of a unit attacking a area, building by building and block by block built-up area is to seize and clear the entire (par. 426). area. Any tasks, objectives, or other, re^ quirements which will detract from the 50. Phases of the Attack accomplishment of this mission should not a. The attack of a built-up area may be be assigned to an attacking unit. divided into three phases. (1) Phase 1 is designed to isolate the area 49. Tactical Considerations by seizing terrain features dominat- a. Characteristics of built-up areas that ing the approaches to it. Enemy are favorable to the attacker are as follows: defenses or terrain obstacles may (1) The attacker has the advantage of prevent complete isolation. As a maneuver in isolating the town or minimum, the attacker must secure city to be seized. Once the isolation positions outside the built-up area has been completed, the attacker is from which he can support the en- trance to it and the step-by-step in a position either to press the capture of the objective. This phase attack or to contain the defender and of the attack is planned and con- force him to capitulate. ducted in a manner similar to other (2) The attacker may select his point of attacks. See FM’s of the 7- and entry into the built-up area. The 17-series. attack may be conducted from any (2) Phase II consists of the advance to direction, or from more than one the edge of the built-up area and the direction. seizure of a foothold in buildings on (3) The attacker may be able to obtain its near edge. The accomplishment a detailed plan of the built-up area of this phase reduces or eliminates to aid in planning his attack. De- the defender’s ground observation and direct fires on the approaches to fectors or civilians may provide in- the town. The attacker uses the formation to the attacker. cover and concealment in the foothold (4) The attacker may be able to bypass area to displace weapons and to com- strongly defended buildings by going mence his systematic clearing of the under them, using cellars, sewers, area. Planning and conduct of this subways, or other underground pas- phase are much the same as for other sages. Other strongly held defensive attacks of strong defensive positions. positions may be bypassed by attack- An attack against an area of strong ing over the roofs of buildings. masonry buildings that have been b. Each building and block in a built-up extensively prepared may assume area may be a potential fort, since they many of the characteristics of an provide such concealment that the attacker attack on a fortified position. may be unable to determine which is strongly (3) Phase III consists of the advance defended and which is lightly held. Under through the built-up area to clear.it such conditions, the attacker is compelled to of the enemy. During this phase, 32 À*

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Figure 9. A lone infantryman advances rapidly in a built-up area to avoid enemy sniper fire.

the attack assumes more specialized b. Phase I may be accomplished concur- characteristics. Planning of this rently with phases II and III. There should phase is carried out in considerable be no pause following completion of phase II. detail to offset the difficulties of con- Units should move rapidly to deepen the trol. The attack is characterized by penetration before the defender can react. semi-independent action of small As the planning and conduct of phase I is units to accomplish the methodical similar to other ground attacks, the re- clearance of assigned zones. This mainder of the discussion in this chapter is phase of the attack ends when the devoted to phase II, seizure of a foothold, and entire area is cleared. phase III, clearance of the built-up area.

Section II. PLANNING 51. General also covers the essential details of security, combat service support, and the establish- a. Plans for the attack of a well-defended, ment of the communication system necessary built-up area must be based upon a detailed for control. study of the city as well as the enemy dis- b. In an attack of a larger built-up area, positions in and around it. As in any other one or more brigades may be in the attacking attack, planning must provide for a scheme echelon. In this case, a battalion may be of maneuver and . a plan of fire support. assigned a mission of sealing and isolating Both are developed concurrency and must the objective, of seizing a foothold, or of clear- be closely integrated. The plan of attack ing all or a portion of the built-up area; but 33 it will normally participate in only one phase mediate objectives. The numbering of the at a time. The battalion may undertake the buildings along the route of attack facili- seizure of smaller built-up areas independ- tates the assignment of objectives and simpli- ently; in this case, it will be required to fies reports of their seizure. To bypass maintain isolation of the town while clearing buildings would be to risk being attacked it. Combined arms company teams may be from the rear. It is necessary to enter and search each building during the progress of required to carry out similar actions in the the attack. Buildings will be assigned as attack of isolated housing areas. In rela- objectives for rifle squads and, if the build- tively small, built-up areas, combined arms ings are large, for rifle platoons. teams of battalion or company size may b. Phase Lines. Phase lines may be em- accomplish the entire maneuver mission ployed to enhance control by regulating the independently. advance of attacking forces. Phase -lines c. The attack is plannedmay be inused three in lieuphases: of objectives. Principal (1) To isolate the city. streets, rivers, and trolley and railroad lines (2) To gain a foothold near the edge of the are appropriate for use as phase lines. city. c. Zones of Action and Boundaries. These (3) To systematically reduce and seize are used at division and lower levels. In control of the entire area. areas of semidetached construction where observation and movement are less restricted, 52. Intelligence boundaries within brigades, battalions, and The scheme of maneuver is based on a companies are normally established in the careful study of available intelligence. Intel- alleys or within the blocks so that both sides of the street are included in one unit’s zone. ligence requirements are established early in However, in the denser portions of the built- the planning, and all available agencies and up area, which contain block-type construc- sources are exploited in an effort to provide tion, boundaries are placed along one side the commander with essential elements of of the street with the street inclusive to one information and other intelligence require- unit. In addition to assigning zones of ments. Emphasis is placed on collecting action, the attack order normally specifies information of the following: that zones are to be cleared of the enemy. a. Location of covered approaches to the d. Checkpoints and Contact Points. Street built-up area. corners, buildings, railway crossings, bridges, b. Location of public utilities. or any easily identifiable feature may be c. Location and nature of obstacles and designated as checkpoints or contact points. prepared defensive positions. These points, respectively, facilitate report- d. Location, strength, and composition of ing of locations and serve as specific points enemy reserves. e. Location and types of enemy weapons where the commander desires units to make positions and command and observation physical contact. posts. e. Time of Attack. In phase II, when ex- tensive open areas must be crossed to get to 53. Control Measures the buildings on the near edge, the attack As communication and observation are re- may be scheduled for the last hours of dark- stricted and control is difficult in the attack ness in order to provide concealment for the of a built-up area, more restrictive control assault troops. Small parties take advan- measures are usually prescribed in the attack tage of darkness to cross streets and other order. open areas, to gain rooftops, to infiltrate a. Objectives. Objectivesenemy defensiveare relatively areas, and to gain positions shallow. In phase II (seizure of a foothold), s from which to launch or support an attack the battalion normally assigns companies during daylight. the first block of buildings as intermediate objectives. When an objective extends to a /. Attack Positions. In phase II, when a street, only the near side of the street is in- coordinated attack is required, units in the cluded. The final objective is the far edge leading echelon may occupy attack positions of the built-up area. Key buildings or groups in which they accomplish last minute prepa- of buildings also may be assigned as inter- ration and coordination. The requirement 34 for a coordinated attack may arise when the the built-up area favor positioning of the edge of the built-up area is abrupt and over- reserve closely behind the attacking echelon. looks large open areas. In order to preserve The reserves displace on order. secrecy and enhance chances for surprise, b. As few or no gaps will exist between attacking troops should remain in the attack attacking units, commitment of the reserve position only as long as final preparations re- to the attack usually involves a passage of quire. Whenever possible, they occupy and lines or a relief in place. Reserves may be leave the attack position during darkness. employed on one or more of the following

I. missions: 54. Formations (1) An attack to exploit a temporary or The formation to be adopted depends on newly discovered enemy weakness. the width and depth of the zone to be cleared, (2) The assumption of the mission of an the character of the area, enemy resistance, attacking element that has become and the formation adopted by the next higher ineffective. command. Normally, the formation of the (3) The reduction of enemy resistance battalion will provide for two companies in that may have been bypassed by the the attacking echelon. Consideration should be given to leading the phase II assault with attacking echelon or may have sub- tanks when available. sequently developed to the rear of the attacking echelon. 55. Frontages (4) Protection of the flanks and rear. (5) Maintenance of contact with adjacent The frontages assigned to units for the units. attack of a built-up area will depend upon the (6) The assistance of adjacent units when enemy strength, size of buildings, and resist- directed by higher headquarters or ance anticipated. Frontages assigned to when such action favors the accom- units must be commensurate with their capa- plishment of the parent unit’s bilities. As a guide only, in block-type con- mission. struction (usually the most difficult portion of a built-up area), a rifle company’s capability 58. Fire Support Plan is one city block. a. Extensive air and artillery bombard- ment may precede the ground attack of a 56. Main and Supporting Attacks built-up area. Incendiary attacks may be In built-up areas, the main attack may be particularly effective; however, the attacker directed toward the capture of a critical area. should use them carefully since the resulting When the terrain or characteristics of the fires may become an obstacle to his advance. area offer equal advantages to attacking Short of complete saturation of a small area, units, or when enemy forces are estimated to air and artillery bombardment of built-up be uniform, a main attack need not be desig- areas with extensive masonry construction nated. This is normally the case at company can do little more than restrict the movem^tj level. The commander may attack initially and lower the fighting efficiency of enemy with equal forces and, based on the situation troops through repeated shock and concus- during the attack, weight the element which sion. Difficult house-to-house fighting must achieves greater success or which develops still be expected. The rubble and debris an advantage. resulting from air and artillery attack may also provide increased cover for the enemy 57. Reserves while creating obstacles for friendly tanks. a. Reserves are employed much the same b. During phase II, supporting fires are as in other attacks. They are kept somewhat directed toward neutralizing enemy observa- closer to the attacking echelon; however, be- tion and weapons while the attacking echelon cause restricted routes of movement may moves to the buildings at the near edge of the increase the time required for their commit- town. Artillery and mortars are most effec- ment to action. Concealment and cover in tively employed against enemy observation 35 and in counterbattery fires. Airburst fire is prescribed sequence, or may be released to effective against rooftop observation posts subordinate units for specific missions or on while smoke may be used to restrict observa- prearranged schedule. tion at lower levels. High explosive (HE) shells with delay fuzes may be effective 59. Communication Plan against troops in the upper floors of buildings, The communication plan should provide for but they will have little effect on occupants of use of wire and radio down to rifle platoon lower floors. Direct fire weapons, including level. Laying wire lines through buildings tanks, antitank guided missiles, recoilless instead of along streets helps to protect them weapons, and machineguns, are employed to from shellfire and tracked vehicles. Since provide neutralizing fires against known and radio communication may be greatly re- suspected positions in the near-edge build- stricted by the surrounding buildings, and ings. Employment of direct fires in this wire lines may frequently be broken by falling phase of the attack may closely resemble that buildings, shellfire or other causes, small of the attack of a fortified position. units should plan to use foot messengers. Since tank units depend heavily on radio c. Close support fires during phase III must communication, special measures are re- be provided primarily by direct fire weapons. quired to maintain communication within These weapons must be placed well forward them and between separated elements of the with the attacking troops. Rifle grenades combined arms formation. Radio communi- or grenade launchers and small mortars cation can be enhanced by operating sets employed well forward will be particularly from the highest possible locations (rooftops effective. Extensive use should be made of or upper stories) and by the relaying of smoke to blind the defender’s forward weapon messages by other stations, including radio relay by Army aircraft. Rooftops and upper positions and enable attacking small units to stories also provide opportunity to use visual cross open areas and approach close to signals to indicate the need for fire, the shift- windows and doorways. Tear gas and field ing and lifting of fires, and/or to announce protective masks should be used whenever the seizure of a building or group of buildings. they will give assaulting groups an advantage Armored personnel carriers or tanks may be inside buildings. Armored personnel used to provide mobile, protected communica- carriers should be used to move troops from tion centers. building to building where open areas are covered by small-arms, machinegun, and 60. Logistical Support high-explosive fire. They should be accom- a. The expenditure of large amounts of panied by tanks to protect them from heavy, ammunition is common in attacks of built-up direct fire weapons. Control is decentralized. areas; therefore, ammunition distributing The effectiveness of mortars and artillery is points should be well forward. Commanders limited by restricted observation, overhead should plan for early resupply of demolitions, cover for enemy troops, proximity of friendly grenades, flame fuel, and small arms and and enemy troops, and the accompanying tank ammunition. Mobile distributingpoints requirement for pinpoint accuracy. Both may be required down to company team level. mortars and artillery can be used to an Consideration should be given to the use of advantage in maintaining interdiction of armored personnel carriers and hand-carry- routes and restricting movement within and ing parties to resupply the attacking echelon. to the rear of the enemy position. Aerial resupply of prepackaged sling loads by helicopter provides a fast means of resupply. d. Portable and mechanized flamethrowers, self-propelled artillery, and combat engineer b. The logistical plan should provide for vehicles are of great value in reducing indi- special equipment to be available early in vidual buildings and fortified positions. Pro- the planning for rehearsal purposes. Ex- visions for support by these weapons must be amples of these items are flamethrowers, made prior to the attack. Control is usually toggle ropes, and grappling hooks. retained at battalion level. The weapons are c. The evacuation of wounded from roof- assigned specific missions in advance, in tops and upper stories of buildings will be 36 difficult and may require additional litter other attack. After the seizure of a foot- bearers and the use of special evacuation hold, the squads are kept well forward and equipment. Debris may prevent ambulances may be attached to attacking company teams from moving into some areas. Plans should or they are retained in general support to include the marking of buildings which con- provide flank security. The missiles are tain wounded personnel. capable of blasting holes in very thick walls 61. Security and destroying enemy positions. Obstacles Due to the close proximity of opposing within the built-up area may restrict their forces and the excellent concealment and movement. cover available to the defender, security during the attack will present a particular d. Mortars. Both 4.2-inch and 81-mm problem. All units must be alert to an mortars are usually employed in general enemy who may be located above or below support of their parent unit. The mortar’s or to the flanks and rear. The battalion high trajectory allows it to be employed reconnaissance (armored cavalry) plátoon against targets behind buildings which can- and reserve units may be given a mission of not be engaged by artillery. High explosive protecting the flanks and rear and of screen- shells with superquick and time fuzes are ing the areas behind the attacking company effective against rooftop targets. Shells teams. with delay fuze settings are used to penetrate 62. Employment of Organic and Supporting thin roofs and neutralize or destroy enemy Weapons positions in the top floors of buildings. Dur- ing the continuation of the attack, the a. Machineguns. Machineguns are em- ployed initially to provide covering fire mortars may be used to provide smoke- during the attack to seize a foothold in the screens to cover the advance of assault area. When a foothold is secured, these elements in streets, parks, yards, and other weapons are quickly moved into the built-up open areas. Forward observers move with area and are kept well forward where they the attacking echelon to adjust fire on can provide supporting fire for the attacking targets requested by the unit commander. echelon. Machineguns fire grazing fire down streets and alleys and across open areas. e. Artillery. The artillery is employed in These fires destroy any enemy driven into its normal role of close support of the attack- the open and prevent the enemy from using ing echelon using direct or indirect fire, as streets, alleys, and open areas as routes for appropriate. Artillery, particularly the self- supply, reinforcement, or maneuver. propelled 155-mm and 8-inch howitzers, pro- b. Recoilless Rifles and Antitank Rockets. vides an excellent means of destroying or These weapons provide antitank protection neutralizing bunkers, heavy fortifications, and may be used to blast holes in walls and or troops in reinforced concrete buildings. knock out enemy strong-points. They are Concrete-piercing 1-55-mm and 8-inch how- well adapted to combat in built-up areas itzer rounds can penetrate 36 and 56 inches because of their light weight, versatility, of concrete, respectively, at a range of 2700 and penetrating power. They cannot be fired meters. Artillery can also be used to neutra- from within rooms, however, unless provi- lize enemy positions on rooftops or in the top sions are made for the escape of the backblast. floors of buildings. During phase III of Recoilless rifles move into the fringe of the the attack, the effectiveness of massed built-up area with the lead elements. Dur- artillery fires will be reduced because of ing the attack within the built-up area, they restricted observation and the proximity are moved with or directly behind the assault platoons to be readily available to fire on of friendly and enemy troops; therefore, targets of opportunity. If obstacles within control of artillery fires is frequently the built-up area do not restrict the move- decentralized. Time fire and proximity-fuze ment of vehicular-mounted weapons, they fire are effective against the enemy on roof- will normally be attached to or placed in tops and behind barricades. Artillery direct support of the lead elements. weapons should be protected against enemy c. Antitank Guided Missiles. The antitank antitank fire in a manner similar to that used squads are employed initially as in any for tanks. 37 /. Tanks. should be assigned to protect spe- (1) When the built-up area is small or cific tanks. lightly defended, the force should (4) See FM 17-1 for details of employment. attempt to drive through or into the g. Nuclear Weapons. It may not be de- town as rapidly as possible using- sirable to use nuclear weapons in conjunc- tanks, if available, as the leading- tion with a ground attack of a built-up area element. In heavy house-to-house because of the casualties which would be and street fighting, tanks support the inflicted on civilian populations, especially movement of infantry by use of their in friendly territory. Frequently, built-up main guns and machineguns to fire areas will contain installations and facilities into buildings and to destroy steeples, such as power and water stations, railroad tall chimneys, and other structures yards, and key buildings. It is desirable to which may contain enemy observers. capture these intact for subsequent use by Tanks provide covering fire for in- friendly forces and the civilian population. fantry for the assault and reduction Plans for and conduct of the attack must of enemy positions. Moving tanks provide for the protection of these facilities remain close to buildings on the sides and installations from friendly fire and for of the streets held by attacking units, preventing the enemy from destroying them. while covering the opposite sides and 63. Reconnaissance Units firing at anything suspicious. Reconnaissance units at all levels normally (2) Infantry units support the movement are employed to protect the flanks and rear of tanks by locating targets, directing of attacking units. The capability for re- the fire of tanks, neutralizing or connaissance and security is somewhat re- destroying antitank weapons, and duced, however, by restricted observation protecting tanks from tank-hunter and mobility in the built-up area. Army teams. aircraft can be utilized to provide reconnais- (3) Streets and alleys constitute ready- sance and security for the ground commander in built-up areas. made fire lanes and firing zones. Vehicular traffic is greatly restricted 64. Engineers and canalized and it is subject to а. Attached or supporting engineers are ambush and close-range fire. Tanks employed well forward and will frequently are at a further disadvantage be- accompany the lead units. cause their main guns cannot be б. Missions accomplished by engineers depressed or elevated sufficiently may include — to fire into the basements or upper (1) Preparation and execution of demo- floors of buildings at close range. litions for use in breaching walls or other obstacles. All bridges and overpasses are (2) Location and assistance in mine checked for mines and boobytraps removal. and for load capacity. Tanks should (3) Clearance of barricades and debris not move singly. Specific riflemen to assist forward movement. Section III. CONDUCT OF THE ATTACK 65. Isolation of the Area66. Seizure of a Foothold Phase I is the isolation of the built-up area a. Phase II is the advance of the attacking and the seizure of terrain features that force to the edge of the built-up area and dominate the approaches into it. The at- seizure of a foothold. It should insure the tacker secures positions outside the built-up elimination of the defender’s ground obser- area from which tq support the entrance vation and direct fires on the approaches into it. The tactics and techniques for this into the built-up area. The attacker uses phase of the operation do not differ from the foothold area to reorganize, decentralize those employed in an attack against other control, and displace weapons to firing posi- well-organized enemy defenses. tions from which the continuation of the 38 attack can be supported. Favorable avenues ■zones of responsibility. Each subordinate of approach' are exploited. Supporting unit must clear , its zpne.completely, leaving weapons are used to neutralize the enemy no enemy in its rear (pars.'68-70). and to isolate the foothold area from support and reinforcement from other parts of the ■b. When the built-up area is small or lightly built-up area. Artillery and mortar fires defended, the attacking force should attempt are used extensively to cover the advance of the attacking units and to prevent the to drive through or into the town- as rapidly enemy from manning crew-served or indi- as possible to seize terrain or buildings and vidual antitank weapons. They may also be enemy routes-into the town from the other used to blow gaps through tactical and pro- side. tective wire where more efficient means of accomplishing this are not available. Smoke c. Mopping-up operations. shells may be used to screen adjacent areas (1) In a strongly defended built-up area, and to further isolate the foothold area. the leading elements must mop up as Supporting fires are shifted when attacking troops have reached the final coordination they advance. Each building in the line, and leading elements move without assigned zone must be entered and delay to the first buildings to be seized. thoroughly searched for enemy. The initial objective is normally the first This procedure protects leading ele- block of houses in the built-up area. ments from surprise attacks on their rear, secures their lines of communi- b. The probability of success is increased cation, and prevents support and re- if the assault is launched from an unexpected serve units from becoming involved direction and preferably in the early morn- in unexpected mopping-up operations ing just before first light, during other which may hamper their prompt em- periods of reduced visibility, or under cover ployment elsewhere! . of smoke.

c. Combat engineer vehicles, mechanized (2) When a built-up area is. lightly de- flamethrowers, and tanks equipped with fended, it may be desirable for lead- mine detonating devices such as demolition ing elements to push forward rapidly snakes, flails, or rollers should be included .to seize critical areas. In such a in the assaulting force. situation, supporting elements and reserves are given specific mopping- 67. Clearance of the Built-Up Area up missions to clear sections of the Phase III begins without pause after the area which have been bypassed or completion of phase II. Phase III of the only hastily cleared by the leading attack may be either a systematic block-by- units. Close coordination between block, house-to-house reduction of the built- the leading units and the mopping-up up area or a rapid advance through the town units is essential to prevent them with clearance of specific critical areas and from becoming engaged in a fire fight strategic buildings. Clearance and seizure with each other because of mistaken techniques depend upon the mission, size of identity. the town, construction and building arrange- ment, and enemy dispositions and strength. d. Consolidation takes place as each unit Factors governing the selection and execu- objective is taken. Attention is given to tion of the techniques are listed below. placing weapons and men in firing positions to cover all avenues of approach. At this a. When the built-up area is exceedingly time, plans are made or completed for the large and heavily fortified, or when the mis- continuation of the attack. When the entire sion requires a complete clearance of enemy built-up area has been secured, the consolida- forces, a methodical, house-to-house, and tion will be such as to prevent the enemy block-by-block clearance operation is per- from regaining a foothold within the formed. The area is divided into company buildings. 39 Section IV. HOUSE-TO-HOUSE FIGHTING 68. Assault Technique party depends upon the size and character a. The assault and clearance of an indi- of the buildings to be searched. It should be kept small, since an excessively large vidual building or groups of buildings is carried out by a searching party supported searching party leads to confusion and the by the fires of a covering party. This tech- men get in each other’s way. In the search- nique applies to all levels of units. Sup- ing party, the riflemen operate as two-man porting weapons provide covering fires for searching teams under the direction of the larger units, while in the rifle squad one squad or fire team leader. fire team may cover the other team as it d. The individual techniques of members searches. of the searching party are emphasized be- b. The covering party protects and aids cause of the decentralized control involved. the advance of the searching party. It (1) Before entering a room which is normally includes riflemen and grenadiers; believed to contain enemy, the rifle- weapons employed may include machineguns, man throws in a grenade. To take rocket launchers, tanks, and other direct full advantage of the cover available, fire weapons. From selected firing posi- he should be trained to throw with tions, the covering party fires on the build- either hand and from any position. ing to be entered and on any adjacent (2) Riflemen should be trained to fire buildings from which enemy fire can be placed quickly and accurately, either on the . searching party. The searching right- or left-handed, from any posi- party, on seizure of the designated buildings, tion. All portions of a room may not provides covering fires and protection for the be visible to a man entering it (fig. covering party as it displaces. When a street 10). For close combat, emphasis is is the boundary between units, adjacent placed on quick firing rather than use units assist each other with mutually sup- of the bayonet. A fixed bayonet porting fires. makes it more difficult to cross ob- c. The searching party enters and searches stacles and move through small all buildings that the unit is responsible for openings. clearing. The party usually consists of rifle- (3) A searching team of two riflemen nor- men, although special demolition teams may mally is given the mission of search- accompany it. The size of the searching ing one room. One man throws in a

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Figure 10. Corner barricade. 40 grenade, waits for it to explode, then to an upstairs window (fig. 14). Be- enters quickly and places his back fore entering any room that may con- against the nearest wall. The sec- tain an enemy, the rifleman always ond man follows and searches the throws in a hand grenade. room in detail. The searching team 6. Entry on Middle Floor. In many cases, the fire team leader informed it may be impossible to enter a building at of its progress in clearing assigned portions of a building. the top. In these instances, entry should (4) At times it may be desirable or be made at the highest possible point using necessary to create openings in walls the techniques described in a above. The to permit movement from one room floor on which entry is made should be or building to another. “Mouse- thoroughly cleared first. The searching holing”, or creating these openings, party then moves to the top floor and clears can be done with handtools, explo- the building from the top down (fig. 12). sives, or weapons. c. Entry at the Bottom. When entrance must be made at ground level, it is preferable 69. Methods of Entry to use demolitions, artillery, tank fire, or There are three methods of entering and other weapons to blast a new entrance. clearing buildings. Doors or windows are likely to boobytrapped a. Entry at the Top. or covered by enemy fire. When the ground (1) Whenever possible, buildings are floor has been cleared, the searching party cleared from the top down. Heli- moves to the top of the building and works copters may be used to deliver down. assault troops to the roofs of build- ings from which they will fight their way down to bottom floors. En- 70. Techniques of Movement trance through the upper part of the a. Streets, alleys, vacant lots, and other building is preferable because it is open areas offer the best fields of fire to the easier to work down than up (fig. 11). enemy and are avoided whenever possible. An enemy who is forced to the top Open spaces that cannot be avoided are may be cornered and fight desper- crossed quickly. Smoke is used liberally to ately or escape over the roofs, while conceal movement. Routes of advance are one who is forced down to the ground chosen which will not mask the covering fire. level may be tempted to withdraw b. Cover is selected in advance. The at- from the building, thus exposing him- tacker hugs walls and moves rapidly from self to the fire of the covering party. cover to cover. The rifleman rolls quickly (2) Various means such as ladders, over roofs and walls to avoid going over them ■ drainpipes, vines, helicopters, or the upright (fig. 15). He must fire his rifle from roofs of adjoining buildings may be his right shoulder around the right side of used to reach the top floor or roof of a cover and from his left shoulder around the building. In some cases, one mem- left side (fig. 16). He avoids firing over the ber of the team can climb onto the top of cover unless his silhouette blends with shoulders of the other and reach the background. high enough to pull himself up. c. In lightly defended areas, the require- Toggle ropes are also useful. These ment for speed may dictate moving through are short ropes 4 to 6 feet long and the streets and alleys without first clearing about Vi inch in diameter. One end all buildings. Under these circumstances, of the rope has an eye (loop) and the the maneuver element should employ tanks, if available, to lead the column, closely fol- other is tied to a short stick (fig. 13). lowed and supported by infantry. If the Several toggle ropes can be joined infantry is mechanized, it should remain together to form wall-scaling ropes. mounted until forced to dismount, and should By attaching a grappling hook to the remount to cross open areas. When dis- end of a wall-scaling rope, a rifleman mounted, rifle elements move along each side can scale a wall, swing from one of the street with leading squads keeping building to another, or gain entrance approximately abreast of the lead tanks. 41 I*»

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When not accompanied by tanks, rifle ele- ments move single file along one side of the street under cover of fires from supporting \ • weapons. They are well dispersed and move along quickly. Each man in the leading element is detailed to observe and cover a ■»«CS certain area, such as second floor windows on the opposite side of the street. .• «2? 1— d. House-to-house fighting lends itself to surprise situations. Special attention must be given to alertness and all-around secu- .ÈV rity. The attacker must be ready to meet the enemy not only on the front, flanks, and rear, Figure 12. Attack through ceiling and wall. but from above and below as well.

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Section V. COUNTERGUERRILLA OPERATIONS 71. General c. When an urban area has been seized a. Since built-up areas are the most un- by an insurgent force, it must be recap- tured as soon as possible to prevent an favorable terrain for an overt combat ele- apparent success or victory by the guerrilla ment of a guerilla force, such a force will not force, to maintain popular support for the normally choose to fight in these areas until friendly cause, and to free troops for use it has reached the latter phases of its orga- elsewhere. nizational development and has a strength and capability comparable to the conven- tional force. However, clandestine elements 72. Tactical Considerations in cities and towns often incite organized a. The tactics of reducing a barricaded rioting, seize portions of urban areas, erect built-up area (fig. 17) resemble the conven- street barricades, and resist attempts to en- tional tactics of normal street and house-to- ter the area. Noncombatants are sometimes house fighting. held as hostages. b. A cordon is established to surround and b. The objectives of these operations may be solely to conduct resistance, or, more seal off the barricaded area. The cordon is probably, to commit the counterguerrilla established at the next street or road out force to actions against the civil population from the barricaded area which offers good which will result in a gain of sympathizers visibility, fields of fire, and ease of move- for the guerrilla force and make it appear ment. All unauthorized persons are cleared that it is promoting a popular cause. from the intervening area. The cordon 46 I 0.

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0 CORDON AND SCREENING POSTS.

BARRICADED AREA. HIGH BUILDINGS (1 & 2) 0 SHOULD BE CLEARED FIRST.

Figure 17. Reducing a.barricaded urban area. controls all entrances and exits of the en- sible, by employing large armored formations circled area. in the vicinity of the barricades, by firing c. Announcements are made to the insur- indirect fire into uninhabited areas on the gents, by such means as loudspeaker broad- fringe of the barricaded area, and by making casts and leaflets, that the area will be all overt preparations for the attack as attacked at a given time unless the insurgents obvious as possible to the insurgents. lay down their arms, return their hostages 73. Conduct of the Attack safely, and surrender peacefully. Amnesty a. If the insurgents do not surrender, ma- and protection may be offered to those who neuver and fire support elements attack at surrender prior to the attack. the prescribed time and clear the area as d. During the period between the time of rapidly as possible with a minimum of killing the announcement and the time of the attack, of noncombatants and destruction of prop- a show of force in the vicinity of the barri- erty. The cordon remains in place to main- caded area will assist in impressing upon tain security, support the attack by fire the insurgents the hopelessness of defending where possible, and receive prisoners and against the forthcoming attack. This show rescued hostages from the attacking of force may be accomplished by airlifting elements. or parachuting the infantry attack units b. If the area is large, it is either divided into their attack positions as early as pos- into sectors for control purposes or the attack 47 is controlled by the use of progressive phase arouse the hatred of the civil population for lines. As each sector or phase line is cleared, the counterguerrilla force. A very effective the cordon moves to exclude it. Close sur- means of countering «uch-psychological war- veillance of cleared areas is maintained in fare is the use of loudspeaker'announcements case underground passageways are used as and leaflets prior to the attack. These an- escape routes. Succeeding sectors are nounceménts and leaflets categorically state' attacked and cleared one at a time. to the insurgents and the remainder of the c. Commanders must be alert to the psy- civilian population that in the forthcoming- chological after effects of an offensive oper- ation against a barricaded urban area. attack (1) civilians will probably be killed or Innocent civilian adults and children will wounded and (2) the responsibility for such probably be killed and wounded by the action. actions rests entirely on the insurgents, who The guerrilla force will attempt in every way may surrender and negate the necessity for possible to exploit this fact to the utmost to such action.

48 CHAPTER 7 DEFENSE OF A BUILT-UP AREA

Section I. GENERAL

74. General 75. Defensive Considerations a. The use of a built-up area in the organi- a. General. The defense of a built-up zation of a defense depends upon such factors area is organized around key terrain features as its size, its location in relation to the and centers of construction which preserve overall defensive mission, and whether it the integrity of the defense and provide ease affords increased protection. Cities, towns, of movement to the defender. Subter- and villages constructed of flammable ma- ranean systems may be used for the move- terials provide little protection and may ment of forces and may provide protection become a hazard to the defender, while against nuclear attack. They are incorpo- buildings of masonry construction can be rated in the organization of the defense. developed into well-fortified defensive posi- Maximum use is made of rubble and other tions or strong points. Each building and obstacles. Defenses are prepared in depth each block in a town or city of masonry for continuous defense throughout the area. buildings is a potential fort and provides such concealment that the attacker is unable b. Concealment and Cover. The manmade to determine which is strongly defended and obstacles and cover characteristics of built- which is lightly held. This causes him to up areas favor the defender. dissipate his forces, and rubble and debris c. Restricted Movement. Movement of from his fires hinders his advance through vehicles is restricted to the narrow lanes the area and provides added protection for provided by streets and alleys. Movement thé defender. Cellars, sewers, subway tun- of foot troops is also confined, although some nels, thick masonry walls, and reinforced traffic through buildings is possible. Because concrete floors and roofs provide cover for of these difficulties in movement, the com- the defender during heavy bombardments. mitment of large, centrally controlled re- When fires are lifted or shifted, the defender serves for counterattacks within the built-up is able to emerge promptly to meet the enemy area usually is not feasible. assault. d. Observation. Limited observation within b. A built-up area that can be easily the built-up area restricts both the attacker avoided has little defensive value. Thus, a and the defender. built-up area suitable for defense must be e. Communication. Radio communication located so that it forces the enemy to launch a direct attack or make a time-consuming may be impeded by the buildings in the area. maneuver. c. The obstacle effect of built-up areas may 76. Obstacles permit their defense in lesser strength, thus providing economy-of-force. Under some A built-up area is to a degree, an obstacle > conditions, elements of the division may se- in itself since it canalizes and impedes an cure built-up areas while the remainder of attack. Likely avenues of approach are the division is retained in reserve to counter- blocked by obstacles and covered with fire. attack in the open. Consideration should Antitank and antipersonnel obstacles, and also be given to defending on the outskirts toxic chemical agents and fougasses, rein- of outside the built-up area to provide ma- forced with wire entanglements, hold the neuver space for counterattacking forces. attacker under fire while he attempts to 49 breach them. Tank obstacles are impro- ized, the mining and boobytrapping of the vised throughout the built-up area by blow- obstacles, particularly those of rubble and ing. craters, demolishing walls, derailing or debris, are highly effective deterrents to overturning streetcars or railroad cars, and breaching operations. Nuisance mines and by making maximum use of rubble and debris boobytraps, when authorized, are frequently from demolished buildings. When author- placed inside unoccupied buildings.

Section II. PLANNING 77. General integrated into the overall defense plan. a. The area defense is employed when de- They are prepared to continue resistance fending a built-up area. Tue fundamentals even when bypassed and isolated. of defensive combat are generally the same /. When time permits, planning for the as for any other area defense. The differ- defense is detailed and centralized. Since ences are in techniques employed and degree the majority of actions are conducted by of emphasis on certain fundamentals. small units, control is decentralized during b. Because of abundance of concealment the conduct of the defense. and cover but limited observation, special attention must be given to mutual support 78. Scheme of Maneuver and all-around defense to counter enemy а. The development of a scheme of maneu- infiltration. The nature of the terrain usu- ver for the defense of a built-up area is similar to that for other defensive operations. ally leads to close combat with enemy forces. It involves the plan for placement and Therefore, added emphasis is placed on the movement of the organic and attached ma- barricading of streets and the employment neuver units to accomplish the mission. of direct fire weapons. Throughout the development of the scheme c. The forward edge of the battle area of maneuver, the commander considers the (FEBA) should be located near the forward mission, enemy, terrain and weather, and edge of the city or town. This prevents the troops available, and their effect on the plan enemy from entering the outskirts and gain- of defense. ing the advantage of cover, provided by б. Defensive echelons include the security buildings, to deploy his forces. The FEBA area, forward defense area, and the reserve. should not appear as a clearly defined line on which the ¡attacker can mass his supporting 79. Security Echelon fires. Under some conditions, it may be a. The security echelon includes covering necessary or des.irable to locate the FEBA forces, a general outpost, and combat out- back from the edge of the built-up area. For posts (COPL) as in other situations. They example, the character or density of con- cover all approaches to the built-up area and struction along the forward edge may be less provide observation to give warning of suitable for defense than buildings nearer enemy approach, adjust long range fires on the center of the town or city. Portions of the attacker, and deceive the enemy as to the the FEBA may also be withdrawn within true location of the FEBA. They accomplish the built-up area to deceive the enemy as to their missions by delaying and disrupting its true location. the enemy advance. d. All echelons of units are assigned spe- b. Local security elements occupy fox- cific areas to be defended. Positive meas- holes outside of buildings at night and move ures are taken to maintain continuous inside the buildings during daylight hours. surveillance over the entire area and to de- c. When the COPL is well forward of the fend oh short notice in any direction. De- edge of the built-up area, tanks may be em- fenses are tied together to prevent ployed with the combat outpost. Due to encirclement and penetration. their limited maneuverability in restricted e. Key buildings or groups of buildings areas, however, tanks are not usually em- that, are strongly constructed and well sited ployed with the combat outpost when the out- for defense may be strongpoints. These are post is on or near the edge of the built-up 50 area and can be supported by tanks on the toons are as stated in paragraph 77. With FEBA (fig. 18). two platoons forward, the forward rifle com- pany may be assigned a frontage of two to four city blocks, and a depth of two to three city blocks. This minimum figure applies in areas of dense, block-type construction, multistory buildings and underground passages. (1) Rifle platoons along the FEBA are assigned one or two blocks to defend, depending on the character of build- ing construction. Large, strongly constructed buildings such as court- houses, post offices, or public utility buildings may require occupation and % defense by an entire platoon. Each individual is assigned a sector of fire and several firing positions. By frequently shifting his firing position, a rifleman can cover his sec- tor and deceive the enemy as to his true location. Machineguns are em- ployed to place flanking, grazing- fire across the front of the FEBA. They are usually placed at ground level to achieve maximum grazing fire. Rifle platoon antitank weapons * are located to command street inter- sections. They may be located in Figure 18. Tank movement restricted by built-up area upper floors to gain better observa- and rubble. tion and fields of fire. They, too, must have several alternate posi- tions. The platoon leader must de- 80. Forward Defense Forces vote special attention to security a. The determination of the size of forces against entry into the platoon area to be employed on the FEBA, the width of from the flanks, rear, overhead, or the sector assigned to each unit, and the underground. Specific individuals specific locations of defensive positions are designated to perform these depend upon the mission; size, trafficability, tasks. and natural defensive strength of the area to be defended; enemy capabilities; and capa- (2) Tank elements of the company team bilities of the defender. and antitank weapons of the weapons b. Defense of the FEBA normally is as- platoon are employed to cover the signed to infantry battalions or infantry- more dangerous avenues of armor heavy battalion task forces. Battalions are approach. They are usually used in usually assigned frontages of from four to conjunction with barricades along eight city blocks (an average city block is the FEBA, in which case they may be approximately 175 meters) and a depth of attached to a rifle platoon. When three to six city blocks. Battalions normally streets entering the company area employ two companies forward and retain one in reserve. are numerous, tanks and antitank c. Forward companies normally employ weapons may be employed under two platoons forward and one in reserve. company control and positioned in Factors influencing the disposition of pla- depth. In either case, supplemen- 51 tary positions are selected and ing surveillance of the rear area, elements prepared to cover other streets enter- of the reserve may prepare special covered ing the area from the front, flanks, routes through buildings for use during and rear. counterattack. (3) The 81-mm mortar section is em- ployed in general support. Diffi- 82. Reconnaissance Platoon culty may be encountered in finding- Prior to withdrawal of the general outpost, positions which provide adequate the reconnaissance platoon may be employed mask clearance. When the company forward of the COPL as in other defensive position is very shallow, ■ mortars situations. Its mobility, communications, may be emplaced in the battalion and firepower particularly suit it for security reserve area and support the com- and warning missions. Following with- pany from that location. In plan- drawal of the outpost, the reconnaissance ning concentrations, priorities are platoon is used on the flanks and rear or in given to streets and other open areas patrolling of rear areas. The platoon’s as well as areas containing lightly mobility is greatly reduced within the built- up area, where scouts and riflemen must constructed buildings. Extensive usually operate dismounted. Close-in pro- use of illuminating fires is planned tection by riflemen must be provided for the for the hours of darkness. Due to antitank weapons or tanks. The platoon the excellent cover normally afforded may assume security missions of reserve defending troops in a built-up area, rifle companies or become a part of the airburst concentrations may be reserve when the primary reserve is planned much closer to friendly posi- committed. tions than in other situations. (4) Reserve platoons of the forward com- 83. Boundaries and Coordinating Points panies prepare positions to limit pen- Boundaries are usually located in streets etrations, defend against attack from or alleys with coordinating points at street the flanks and rear, maintain surveil- intersections. When a street is designated lance over areas not assigned to for- as a boundary, responsibility for both sides ward platoons, support forward of the street is given to one unit. In order platoons by fire (primarily with ma- to provide properly for a coordinated defense, chineguns and antitank weapons or rear boundaries are usually designated. tank main guns), and prepare to counterattack as required. Small 84. Preparation of the Defensive Area unit counterattacks are more com- mon in the defense of built-up areas a. Priority is given to erection of obstacles than in most other defensive situa- to the movement of enemy combat vehicles. tions. They are launched promptly . In the forward area, streets are blocked by to regain key individual buildings or craters, rubble, or barricades made of locally groups of buildings that have been available material. Buildings may be demol- lost to, or contain, the enemy. Coun- ished to provide material for the construction of obstacles. Wire entanglements and anti- terattacks may be executed at night. personnel mines are added to prevent pas- 81. Reserve Company sage by foot troops and to hamper efforts to Reserve companies are employed in the remove the obstacles. Enemy riflemen who defense of a built-up area in much the same will attack through buildings are at a consid- manner as in other area defenses. Due to erable disadvantage when their supporting tanks are unable to mqye abreast of them in restricted routes of movement and the the streets. Street barricades are closely abundance of concealment and cover, reserve coordinated with antitank and small arms companies are usually somewhat closer to fires. Movable barricades are prepared forward companies than in open terrain. for use in rear areas. In addition to the usual reserve tasks of b. Buildings that contribute most to the preparing blocking positions and maintain- general scheme of defense are selected for 52 occupation. Mutual support between de- aperture. Exclusive use of windows is fended buildings is essential. Within the gen- avoided. Interior rooms should have loop- eral plan for defense, buildings are selected holes opening into adjoining rooms. that offer the best fields of fire and obser- vation, good defenses on all sides, and good cover from enemy fires. Buildings should A be carefully inspected to determine de- fensive strengths and weaknesses. Many structures that appear to be strong may have thin veneer walls and offer little protection. Outside appearances should be altered as little as possible to avoid attracting attention. Unoccupied buildings are barricaded within to prevent easy entry by the enemy. Booby- traps, when authorized, may be used in & vacant buildings. Buildings, or portions of them, which obstruct fields of fire may be demolished. j-fC " c. Windowpanes are knocked out to prevent •A, injury from flying glass. Openings are C» screened or closed to keep out grenades. J Curtains may be hung over the upper portion « of openings to darken the rooms and prevent observation. Unoccupied buildings and /J. 7 □) rooms are similarly prepared. 7 r« / ■■A/ M d. There should be an ample number of B loopholes (firing ports) so that when a man has fired from one, and thereby possibly dis- closed his position, he can move to another. A Loophole behind vine. The most effective loopholes are usually B Tiles lifted on roof. Dark patches are painted on those near the ground (fig. 19). Places that roof as dummy loopholes. C Loophole under shadow of porch. D Loophole at ground level behind bush. E Loophole under the eaves. Dummies should be Wl painted all along under the gutter. Figure 20. Loopholes in unexpected places. 5»' Steffi m. e. When windows or large openings are used as loopholes, firing positions should be m m<9i ¡?í.V> well back in the room to provide concealment for the firer. The area in front of the weapon should be cleared or dampened to keep dust kicked up by the muzzle blast from giving away the position. Firing positions within the room are reinforced with . or other firing rests are provided to conform to the position of the loophole. f. If possible, two exits from each occupied room should be kept open. Holes for move- ment from one room to another are made in concealed places such as behind heavy furni- Figure 19. Typical firing ports and observation slits in wall of masonry building. ture or under stairs. Openings are located so the enemy cannot see into the room. Doors used by the defender are sandbagged to pro- provide the element of surprise are used vide bulletproofing and the minimum opening whenever possible (fig. 20). It may be desir- necessary for passage. able to knock out a few bricks or make a small g. One or more well-camouflaged and sand- hole in the corner of a building for a firing bagged observation posts are prepared in 53 attics or on upper floors. These locations or when suitable firing positions are not may also be used for sniping. They are available within the battalion area, the 4.2- particularly useful when entry over the roofs inch mortars may be positioned behind the or through upper floors is possible. Struc- reserve. tural features such as drain pipes, which b. Davy Crockett. The battalion Davy may help the enemy gain entrance through Crockett section is normally employed in upper floors, should be removed. general support, and it is positioned to en- h. As time permits, the fortification of gage enemy targets forward of the FEBA. buildings used for defense is improved. Likely target areas are selected and firing The ceilings of cellar dugouts are reinforced data are computed in advance for the deliv- to provide bomb-proof shelters. Upper floors are bulletproofed with sandbags. Walls are ery of on-call nuclear fires. reinforced and sandbagged. c. Tanks. Tanks are used to provide anti- i. Fires are a particular hazard to the de- tank defense and to serve as a part of the fender. Flammable trash must be cleared reserve for the execution of counterattacks. away and gas and electricity turned off. Tanks may be attached to forward rifle com- Firefighting equipment must be collected panies to engage enemy armor forward of throughout the area and kept close at hand. the battle area (par. 79c). Sand and water are stored for future use. d. Artillery. Exits (covered if possible) are required for (1) The supporting artillery units should rapid escape from burning buildings. be located and echeloned so as to permit the delivery of fires to support 85. Fire Support Planning all phases of the defense. Artillery a. Due to the narrower frontages normally is positioned to permit the massing assigned in the defense of built-up areas, of its fires on critical avenues of continuous final protective fires to break up approach. the enemy assault are usually possible. (2) Initially, the artillery delivers long- Final protective fires include direct fires, range fires in support of the security allocated barrages of supporting artillery echelon, with close-in fires and bar- and mortars, and organic mortars. Bar- rages designed to engage the enemy rages cover dangerous avenues of approach as he approaches the FEBA and into the built-up area. break up his assault. Ffres are also b. As with a defense in depth on open ter- planned for the support of counter- rain, plans are made to bring the enemy attacks. under fire at long range and subject him to e. Antitank Weapons. Antitank weapons increasingly heavy fire as he approaches the are positioned to cover the front and flanks. battle area; to stop his assault with final pro- Elements of the battalion antitank platoon tective fires immediately in front of the may be attached to forward rifle companies, battle area; and to eject him by counter- with priority given to those units covering attack from within the built-up area if he armor approaches. Company antitank weap- succeeds in penetrating it. ons are located in each rifle platoon area to 86. Employment of Organic and Support- fire against enemy armor, grouped person- nel, and crew-served weapons. ing Weapons a. Mortars. The 4.2-inch mortars normally are employed in general support. Desirably, 87. Engineers the 4.2-inch mortars are emplaced within or Supporting engineers assist in the organi- near an occupied position of the battalion zation of the defense by preparing street reserve to preclude displacement in the barricades and other obstacles (par. 76), event of a minor penetration. Mortar posi- using demolitions, mines, wire, and rubble. tions with adequate mask clearance may be Obstacles are integrated into the division limited within the built-up area, and this fac- barrier plan. If time permits, the engineers tor may dictate the exact location of the may provide special equipment and skilled weapons. Occasionally, when the depth of personnel for improving positions, construct- the battalion defensive area is quite shallow ing special fortifications beyond the capabil- 54 ity of the rifle companies, and maintaining ganic means. When practicable, additional routes within the built-up area. telephones are provided to forward elements for communication with subordinate units. 88. Logistical Support Wire is installed in underground passages All types of supplies are dispersed and where possible. stocked in sufficient quantities to sustain b. In addition to security restrictions im- each defense area or center of resistance for posed upon radio traffic, unfavorable operat- a prolonged period in the event it becomes ing conditions in the built-up area may isolated. Ammunition, food, water, and reduce the effectiveness of radios, particu- other critical items are securely stored in larly those in small dismounted infantry bombproof and fireproof shelters, if avail- units. able. Supply and distribution of water for troop consumption and firefighting may 90. Counterattack Plans become a serious problem if local sources of Counterattack plans are prepared by units water become contaminated or destroyed. down to company level. Counterattacks by Plans are made for aerial resupply of critical company reserves are more common in de- items. fense of built-up areas than in defense in open terrain. Prompt offensive action is 89. Communication planned to regain any key building or group a. Maximum use is made of wireof buildings for trans- the enemy may have seized. mitting orders and disseminating informa- Routes through buildings are prepared in tion. Existing commercial wire facilities, advance for movement of the counterattack if operable, may be used to supplement or- force.

Section III. CONDUCT OF THE DEFENSE 91. Conduct of the Defense increased fires and by close combat in the a. As the enemy comes under observation streets and within buildings. Flat trajectory of security elements, he is subjected to individual and crew-served weapons, grenade long-range artillery fires. Tactical air, if launchers, and hand grenades become the available, will be used to delay the enemy primary means of defense within the built-up advance and inflict maximum casualties. area (par. 84). Each unit holds its assigned Nuclear weapons may 'also be employed if area at all cost to maintain the continuity of suitable targets are located and developed. the defense. Gaps between units are closed Prior to withdrawal, the security elements by fires or by elements of their reserves. delay, deceive, and disorganize the enemy to d. Observation must be maintained at all the maximum extent possible without be- times. Observers in upper floors must be coming decisively engaged. able to spot enemy parties attempting to b. Upon withdrawal of the combat out- breach a wall or otherwise gain entry. Hand post (COP), FEBA forces engage enemy grenades thrown or dropped out of windows targets as they appear, or fire against suspect may be effective. Successful entry of a de- or likely enemy assembly areas or other posi- fended building must be made known to all tions. Low-yield nuclear weapons (to in- occupants without delay. Immediate efforts clude the Davy Crockett) may be fired against are made to seal off and destroy the intruders. on-call targets. Further delay is accom- When ordered to withdraw from a portion of plished by previously prepared obstacles a building, troops withdraw toward prepared such as antitank and antipersonnel mine- exits, preferably in upper floors. They use fields, barricades, and barbed wire. demolitions to create new openings when c. When the enemy reaches an area from necessary. which he can launch an assault, final protec- tive fires are executed to disorganize the attacking forces and inflict maximum casual- 92. Employment of Reserves ties. If the attacker succeeds in reaching Reserves are used to eject the enemy before the battle area, resistance is continued by he can seize a foothold and consolidate and 55 enlarge his penetration. They accomplish accordance with previously prepared plans. this by blocking or counterattacking pene- The restrictions to observation with built-up trating elements. Initially, all available fires areas require that extremely close coordina- are directed at the penetrating force, during tion of fires be achieved between the counter- which designated forces counterattack in attack force and adjacent units.

56 APPENDIX I REFERENCES

AR 105-87 Electronic Warfare. FM 19-40 Handling of Prisoners of War. AR 320-5 Dictionary of United States Army. FM 20-32 Warfare. Terms. FM 20-33 Ground Flame Warfare. AR 320-50 Authorized Abbreviations and FM 20-60 Battlefield Illumination. Brevity Codes. FM 21-5 Military Training. ‘ FM 1-15 Aviation Battalion, Infantry, Air- FM 21-6 Techniques of Military Instruction. -r <'•- borne, Mechanized and Armored FM 21-10 Military Sanitation. ! Divisions. FM 21-11 First Aid for Soldiers. \* FM 1-100 Army Aviation. FM 21-18 Foot Marches. FM 3-5 Chemical, Biological, and Radio- FM 21-20 Physical Training. logical (CBR) Operations. FM 21-26 Map Reading. FM 3-10 Chemical and Biological Weapons FM 21-30 Military Symbols. Employment. FM 21-40 Small Unit Procedures in Chemical, - (S) FM 3-10A Chemical and Biological Weapons Biological, and Radiological (CBR) Employment (U). Operations. FM 3-12 Operational Aspects of Radiological FM 21-41 Soldier’s Handbook for Chemical Defense. and Biological Operations and FM 5-1 Engineer Troop Organizations and Nuclear Warfare. Operations. FM 21-48 Chemical, Biological, and Nuclear FM 5-15 Field Fortifications. Training Exercises and Inte- FM 5-31 Use and Installation of Boobytraps. grated Training. FM 5-34 Engineer Field Data. FM 21-50 Ranger Training and Ranger FM 5-135 Engineer Battalion, Armored, Operations. Mechanized, and Infantry Divi- FM 21-60 Visual Signals. sions. FM 21-75 Combat Training of the Individual FM 5-136 Engineer Battalion, Airborne Divi- Soldier and Patrolling. sion. FM 21-76 Survival. FM 6-20-1 Field Artillery Tactics. FM 21-77 Evasion and Escape. FM 6-20-2 Field Artillery Techniques. FM 22-100 Military Leadership. FM 7-11 Rifle Company, Infantry, Airborne FM 23-20 Davy Crockett Weapon Systems in Infantry, and Mechanized In- Infantry and Armor Units. fantry. FM 24-18 Field Radio Techniques. FM 7-15 Infantry, Airborne Infantry, and FM 24-20 Field Wire and Field Cable Tech- Mechanized Infantry, Rifle Pla- niques. toons and Squads. FM 25-10 Motor Transportation, Operations. FM 7-20 Infantry, Airborne Infantry, and FM 27-10 The Law of Land Warfare. Mechanized Infantry Battalions. FM 30-5 Combat Intelligence. FM 7-30 Infantry, Airborne, and Mecha- FM 30-7 Combat Intelligence: Battle Group, nized Division Brigades. Combat Command, and Smaller FM 11-50 Signal Battalion, Armored, Mecha- Units. nized and Infantry Divisions. FM 30-10 Terrain Intelligence. FM 11-57 Airborne Division Signal Battalion. FM 30-16 Technical Intelligence. FM 17-1 Armor Operations. (S) FM 30-18 Collection Intelligence Operations, FM 17-15 Tank Units, Platoon, Company, and Intelligence Corps, U.S. Army (U). Battalion. FM 31-10 Barriers and Denial Operations. FM 17-30 The Armored Division Brigade. FM 31-15 Operations Against Irregular FM 17-36 Divisional Armored and Air Cavalry Forces. Units. FM 31-16 Counterguerrilla Operations. FM 17-95 The Armored Cavàlry Regiment. FM 31-21 Guerrilla Warfare and Special FM 19-15 Civil Disturbances and Disasters. Forces Operations. FM 19-25 Military Police Traffic Control. (C) FM 31-40 Tactical Cover and Deception (U).

57 (CM) FM 32-5 Communications Security (U). TC 7-3 Antipersonnel Weapon (Claymore) FM 33-5 Psychological Operations. M18 and MISAI. FM 41-5 Joint Manual of Civil Affairs/Mili- (C) TC 100-1 Employment of Nuclear Weapons tary Government. (U). Civil Affairs Operations. FM 41-10 TC 101-2 Tactical Operations Centers. FM 54-2 Division Logistics and the Support TM 3-200 Capabilities and Employment of Command. Toxic Chemicals. FM 57-35 Airmobile Operations. Fallout Prediction. FM 61-100 The Division. TM 3-210 (S) FM 100-1 Doctrinal Guidance (U). TM 3-220 Chemical, Biological, and Radio- FM 100-5 Field Service Regulations; Opera- logical (CBR) Decontamination. tions. TM 5-280 Foreign Mine Warfare Equipment. FM 101-5 Staff Officers’ Field Manual; Staff TM 9-1940 Land Mines. Organization and Procedure. TM 9-1946 Demolition Materials. FM 101-10, Part II Staff Officers’ Field Manual; Orga- TM 57-210 Air Movement of Troops and nizational, Technical and Logis- Equipment. tical Data. DA Pam 108-1 Index of Army Motion Pictures, (S) FM 101-31-2 Staff Officers’ Field Manual; Nu- Filmstrips, Slides and Phono- « clear Weapons Employment (U). Recordings. (S) TC 3-7 Capabilities and Employment of DA Pam 310-Series Military Publications Indexes. ■ 'Oe Biological Agents (U). DA Pam 750-1 Preventive Maintenance Guide for TC 3-10 Defense Against V-Agents. Commanders.

58 APPENDIX II TRAINING

1. Objectives coordinated teams for the accomplish- The objectives of training for combat in ment of specific tasks. Rehearsals fortified or built-up areas are as follows: and the study of aerial photos and a. Train individuals and units in the proper terrain models contribute to develop- tactics and techniques for the attack or ment of proficiency. Emphasis is defense of fortified or built-up areas. placed upon the training of platoon- b. Train individuals and teams in the use size assault teams and on the coordi- of special-purpose assault equipment and nation of fire support and maneuver weapons. elements. c. Train the individual in the peculiarities b. Built-up Areas. When training for the and techniques of the enemy in fortified or attack of a specific area, most of the training built-up area fighting. time is devoted to technical training (use of d. Prepare the individual soldier psycho- special equipment) and the practical applica- logically for successful combat in a fortified tion of tactics and techniques for the specific or built-up area. area to be attacked. Whenever possible, e. In the case of the attack, make the both tactical and technical training should individual completely familiar with the par- be conducted in a built-up area similar to ticular area in which the attack is to be con- the one to be attacked. ducted. (1) Special technical training for the attack of a built-up area should em- 2. Training for the Attack phasize the following: a. Fortified Areas. Practical application (a) Development of proficiency in the and realism are stressed throughout all use of special-purpose weapons and training. Both technical training (use of equipment. special equipment) and tactical training are (b) Use of demolitions. conducted in terrain similar to that in the (c) Boobytraps and mine warfare. fortified area to be attacked. (d) Passage of obstacles common to (1) Special technical training for the built-up areas. attack of a fortified position should (e) Peculiarities and techniques of the emphasize the following: enemy in built-up area fighting. (а) Development of proficiency in the (/) Plan and characteristics of the area use of special-purpose weapons. to be attacked. (б) Use of demolitions. (c) Breaching of minefields. (g) Establishment and use of special (d) Passage of obstacles. communication techniques. (e) Peculiarities and techniques of the (h) Use of flamethrowers. enemy in defense of fortified areas. (2) Special tactical training for the (/) Layout and characteristics of the attack of a built-up area should em- fortified area. phasize the following: (g) Establishment and use of special {a) Fire and maneuver by small units in communication techniques. built-up areas. (2) Special tactical training must be (6) Techniques of entry and search of directed toward developing well- buildings. 59 (c) Techniques of individual fighting fensive force must participate in in close quarters. alerts. Emphasis is placed upon (d) Techniques of infantry-tank team- frequent rehearsals of the counter- work. attack plans. 3. Training for the Defense b. Built-up Areas. Training for the de- fense of a specific built-up area is usually a. Fortified Areas. Special training for the conducted on the site. Training is accom- defense is usually conducted in the posi- plished concurrently with preparation of tions to be defended. the defense. (1) Special technical training should stress the following: (1) Special technical training for the (a) Installation of mines. defense of a built-up area should (b) Construction of obstacles. include — (c) Construction of shelters and em- (а) Construction of obstacles. placements. (б) Selection and preparation of build- {d) Development of proficiency in the ings to be defended. use of any special-purpose or addi- (c) Peculiarities and techniques of the tional weapons. enemy in built-up area fighting. (e) Establishment and use of special {d) Installation and proficiency in the communication techniques. use of special communication (2) Special tactical training stresses re- techniques. hearsal of all individuals and units (2) Special tactical training for defense in their defensive roles. To the ex- of a built-up area should include — tent permitted by installed obstacles, (а) Thorough indoctrination of individ- the aggressor is used to maneuver uals in the plan of defense. against security forces and forward (б) Training of individuals in fighting forces, and to require commitment of in close quarters. reserves to counterattack or occupy (c) Simulated attacks to rehearse in- blocking positions. Alerts of the dividuals and units in their defen- defensive garrison are conducted sive roles. realistically, frequently, and at vary- (d) Training of units in fighting when ing hours. All elements of the de- isolated from other friendly units.

60 INDEX

Paragraphs Pages Paragraphs Pages Action, zones of 53 34 Attacks of fortified areas —Continued Antitank weapons 26,62, 16,37, Missions — Continued 86 54 Rifle companies 13 11 Artillery 26,62, 16,37, Night attacks 19 13 86 54 Reconnaissance: Attack, conduct in built-up area: By fire 17 13 Area clearance 67 39 By probes 17 13 Area isolation 65 38 Attack, phases of 50 32 Assault technique 68 40 Attack plans for fortified area:' Attack, conduct of 73 47 Control measures 23 15 Counterguerrilla operations 71 46 Engineers 27 19 Entry to buildings, methods of 69 41 Fire support, plan of: Movement in area, techniques of 70 41 Nonnuclear fires 25 15 Seizure of foothold 66 38 Nuclear fires 25 15 Tactical considerations 72 46 Formations 22 14 Attack of built-up area: Frontages 24 15 Battle control measures 53 34 Organic, supporting weapons, use of: Communications 59 36 Antitank 26 16 Engineers, use of 64 38 Artillery 26 16 Fire support plan 58 35 Chemical agents 26 16 Formations, attack 54 35 Davy Crockett 26 16 Frontages 55 35 Flamethrowers 26 16 Intelligence requirements 52 34 Mortars 26 16 Logistical support 60 36 Nuclear weapons 26 16 Main, support attacks 56 35 Tanks 26 16 Organic, supporting weapons 62 37 Attack platoon tasks 30 21 Phases of attack 50 32 Attack training app. II 59 Reconnaissance 63 38 Attacks, night 19 13 Reserves 57 35 Battle area organization 35 24 Security 61 37 Boundaries 83 52 Tactical considerations 49 32 Built-up areas: Attacks of fortified areas: Block-type construction 40 27 Communications, use of 18 13 Critical areas 40 27 Considerations, general: Detached-, semidetached-buildings 40 27 Advantages of defense 14 11 Isolated housing 40 27 CBR weapons, use of 14 11 Key buildings 40 27 Disadvantages of defense 14 11 Built-up areas, combat in: Psychological warfare, use of 14 11 Clearance 67 39 Considerations, special: Isolation 65 38 Airborne-airmobile forces, use of .... 15 12 Seizure 66 38 Assault elements 15 12 Captured enemy material-positions, Check, contact points 52 34 use of 15 12 Chemical agents, toxic 26 16 Chemical-biological agents, use of... 15 12 Civilians, control of 47 30 Fire plan details 15 12 Combat in built-up areas: Reserves 15 12 Civilians, control of 47 30 Selection of area of penetration 15 12 Fire support 43 29 Intelligence: Intelligence: Aerial surveillance 16 12 Information sources 42 28 Infrared photos.. 16 12 Planning 42 28 Topographic maps 16 12 Reconnaissance 42 28 Missions: Terrain 42 28 Attacking echelon 13 11 Looting, control of 46 30 Battalion, basic element 13 11 Night operations 45 30 Platoons 13 11 Security 44 30

61 Paragraphs Pages Paragraphs Pages Combat in built-up areas —Continued Grappling hook 69 41 Tactical considerations 41 27 House-to-house fighting: Communications 18, 37, 13, 25, Assault technique 68 40 59. 89 36. 55 Methods entry 69 41 Coordinating points 83 52 Movement techniques.. 70 41 Conduct of attack 29, 73 20, 47 Intelligence 16, 12, Control measures 23, 53 15, 34 42, 52 28, 34 Counterattack plans 90 55 Japanese fortifications. 4 4 Counterguerrilla operations 71 46 36, 55 Davy Crockett 26, 86 16, 54 Logistical support 60, 88 52 Defense conduct 39, 26, Loopholes 84 84, 91 52, 55 Looting 46 30 Defense of built-up area: Machineguns 62 37 Area defense preparations 84 52 Maginot line 4 4 Boundaries, coordinating points... 83 52 Maneuvers ••••■ 21,78 14, 50 Conduct of defense : 91 55 Mannerheim line 4 4 Considerations 75 49 Missions 13 11 Communications 89 55 Mortars 26, 16, Counterattacking 90 55 62, 86 37, 54 Fire support plans 85 54 Night attacks 19 13 Forward forces 80 51 Night operations 45 30 . Logistical support 88 55 North Korean-Chinese fortifications 4 4 Maneuver, scheme of '. 78 50 Nuclear warfare defense 34 24 Obstacles 76 49 Nuclear weapons •• 26, 46 16, 30 Organic, supporting weapons 86 54 Obstacles: Plans of defense 77 50 Antiairborne H 10 Reconnaissance 82 52 Antiairlanded H 10 Reserve forces 81,92 52,55 Antimechanized 10 10 Security echelon 79 50 Antipersonnel - 9 9 Defense of fortified area: 9 Battle area, organization 35 24 Natural 8 Obstacles, general 76 49 Fire support 36 25 Communications 37 25 Planning, fire support 25, 36 15, 25 Considerations 33 23 Platoon attack tasks 30, 31 21, 22 Nuclear warfare 34 24 Reconnaissance. 17, 13, Defense training app. II 59 63, 82 38, 52 Defensive considerations 33, 23, 56, 35, 75, 80 49, 51 Reserves. 81, 92 52, 55 Engineers 27, 19, 4 4 64, 87 38, 54 Russian fortifications. Fire support 43, 29, Security. 44, 30, 58, 85 35, 54 61, 79 37, 50 Firing ports 84 52 Siegfried line. 4 4 Flamethrowers 26 16 Smoke 26 16 Formations 22 14 Tactical considerations. 41, 27, Fortifications: 49, 72 32, 46 Fortified area 5, 7 8 Tanks. 26, 16, 1, 5 3, 8 Fortified belt 62, 86 37, 54 Fortified locality 1, 5 3, 8 Toggle rope, grappling hook 69 41 Fortified position 5 8 Toxic chemicals 26 16 Fortified zone 1, 5 3, 8 Training: Fortified area attack: For attack app. II 59 Communications 18 13 For defense app. II 59 Considerations, general 14 11 Considerations, special 15 12 World War II fortifications: Intelligence 16 12. Japanese fortifications 4 4 Missions 13 11 Maginot line 4 4 Night attacks 19 13 Mannerheim line 4 4 Reconnaissance 17 13 North Korean-Chinese fortifications... 4 4 Fortified areas 7 8 Russian hedgehops 4 4 Fortified works 6 8 Siegfried line 4 4 Frontages 24, 55 15, 35 Zones of action 53 34 62 By Order of the Secretary of the Army: EARLE G. WHEELER, General, United States Arm.y, Official: . Chief of Staff. J. C. LAMBERT, Major General, United States Army, The Adjutant General.

Distribution: Active Army: USACDEC (5) DCSPER (2) USACECDA (5) USACSSG (5) ACSI (2) USAINTCDA (5) USASDEG (5) DCSLOG (2) USAOCDA (1) USACDC Nuclear Gp (5) CORC (2) USASWCDA (5) US AC AG (5) GRD (1) USAICDA (5) USAWC (25) COA (1) USAADCDA (1) USAARMS (270) V CINFO (1) USAAVNCDA (5) USAAMS (10) TIG (1) USACMCDA (1) USAAVNS (10) TJAG (1) USACACDA (1) USACMLCSCH (10) TPMG (1) USACECDA (5) USACAS (2) TSG (1) USAMPCDA (1) USAES (25) CofEngrs (1) USAMSCDA (5) USAINTS (25) CofCh (1) USAQMCDA (1) USATS (25) OPO (2) USATCDA (5) MFSS (15) USCONARC (10) Armies (5) USASCS (15) ARADCOM (1) Corps (3) USASWS (10) USADC (20) Div (2) USAQMS (5) LOGCOMD (1) Div Arty (1) USAIAS (5) USAAGCDA (1) Bde (5) Units organized under following USAARMCDA (5) Regt/Gp (3) TOE: USAARTYCDA (5) Inf Bg (5) 17-22 (1) USACBRCDA (5) Bn (5) ' USACARMSCDA (5) Co/Btry (5) NG: Stàte AG (3); Units-Same as Active Army except allowance is one copy to each unit USAR: Same as Active Army except allowance is one copy to each unit. For explanation of abbreviations used, see AR 320-50.

U S GOVERNMENT PRINTING OFFICE . 1964 OL—719-500

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o o o o FM 31-bO 'COMBAT iri FORTIFIED AND BUILT-UP AREAS—1964