Boeing B-29 Superfortress

 Design and development  began work on pressurized long-range in 1938, in response to a Army Air Corps request. Boeing's design study for the Model 334 was a pressurized derivative of the Boeing B-17 Flying Fortress with nosewheel undercarriage.  Although the Air Corps did not have money to pursue the design, Boeing continued development with its own funds as a private venture.  The Air Corps issued a formal specification for a so-called "superbomber", capable of delivering 20,000 lb (9,100 kg) of to a target 2,667 mi (4,290 km) away and capable of flying at a speed of 400 mph (640 km/h) in December 1939.  It featured a pressurized cabin, all dual wheeled, tricycle landing gears, and a remote, electronic -control system that controlled four turrets.  Boeing received an initial production order for 14 service test aircraft and 250 production bombers in May 1941, this being increased to 500 aircraft in January 1942.  The first prototype made its maiden flight from , Seattle on 21 September 1942  Manufacturing the B-29 was a complex task. It involved four main-assembly factories: a pair of Boeing operated plants at Renton, (Boeing Renton), and Wichita, Kansas (now Spirit AeroSystems), a Bell plant at Marietta, Georgia ("Bell-Atlanta"), and aMartin plant at Omaha, Nebraska ("Martin-Omaha" - Offutt Field).

B-29 Superfortress General characteristics

Crew: 11 (Pilot, Co-pilot, Bombardier, Flight Engineer, Navigator, Radio Operator, Observer, Right Gunner, Left Gunner, Central Fire Control, )

 Length: 99 ft 0 in (30.18 m)  Wingspan: 141 ft 3 in (43.06 m)  Height: 27 ft 9 in (8.45 m)  Wing area: 1,736 sq ft (161.3 m²)  Aspect ratio: 11.50:1  Empty weight: 74,500 lb (33,800 kg)  Loaded weight: 120,000 lb (54,000 kg)  Max. weight: 133,500 lb (60,560 kg) ; 135,000 lb plus combat load  Powerplant: 4 × Wright R-3350 -23 and 23A Duplex-Cyclone turbosupercharged radial engines, 2,200 hp (1,640 kW) each  Zero-lift drag coefficient: 0.0241  Drag area: 41.16 ft² (3.82 m²)

Performance

 Maximum speed: 357 mph (310 knots, 574 km/h)  Cruise speed: 220 mph (190 knots, 350 km/h)  Stall speed: 105 mph (91 knots, 170 km/h)  Range: 3,250 mi (2,820 nmi, 5,230 km)  Ferry range: 5,600 mi (4,900 nmi, 9,000 km,[75])  Service ceiling: 31850 ft [24] (9,710 m)  Rate of climb: 900 ft/min (4.6 m/s)  Wing loading: 69.12 lb/sqft (337 kg/m²)  Power/mass: 0.073 hp/lb (121 W/kg)  Lift-to-drag ratio: 16.8 Armament

Guns:

 eight or 10× .50 in (12.7 mm) Browning M2/ANs in remote-controlled turrets.[76] (omitted from B-29s)  2× .50 BMG and 1× 20 mm M2 cannon in tail position (the cannon was later removed)[N 11]  Bombs: 20,000 lb (9,000 kg) standard loadout  The nose and the cockpit were pressurized, between fore and aft pressurized sections was a long tunnel over the two bays so as not to interrupt pressurization during bombing. Crews could crawl back and forth between the fore and aft sections, with both areas and the tunnel pressurized. The bomb bays were not pressurized  

. Cockpit

General Electric Central Fire Control system

B-29 Guns  The revolutionary General Electric Central Fire Control system on the B-29 directed four remotely controlled turrets armed with two .50 Browning M2 machine guns each. There were five interconnected sighting stations located in the nose and tail positions and three Plexiglas blisters in the central fuselag. Five General Electric analog computers (one dedicated to each sight) increased the weapons' accuracy by compensating for factors such as airspeed, lead, gravity, temperature and humidity. The computers also allowed a single gunner to operate two or more turrets (including tail guns) simultaneously. The gunner in the upper position acted as fire control officer, managing the distribution of turrets among the other gunners during combat The tail position initially had two .50 Browning machine guns and a single M2 20 mm cannon. Later aircraft had the 20 mm cannon removed,[30]and sometimes replaced by a third machine gun.

 Battle of Kansas

 The combined effects of the aircraft's highly advanced design, challenging requirements, and immense pressure for production, hurried development and caused setbacks. Changes to the production craft came so often and so fast that in early 1944, B-29s flew from the production lines directly to modification depots for extensive rebuilds to incorporate the latest changes.

 the B-29 project was unprecedented in Aviation history: from inception, to drawing board and mass production took three years, at a time when such a design should have taken five years just to become a prototype. Instead the engineering design, production and testing were being undertaken simultaneously, with all of the expected and unexpected problems.

 at the end of 1943, although almost 100 aircraft had been delivered, only 15 were airworthy. The basic design of the B-29 was sound, but significant shortcuts had been taken in the rush to get it into service, causing numerous defects and quality problems.

o The biggest headaches were caused by the new R-3350 engines, which were constantly overheating. the uppermost five cylinders (every 25 hours of engine time) and the entire engines (every 75 hours). . This problem was not fully cured until the aircraft was fitted with the more powerful Pratt & Whitney R-4360 "Wasp Major" in the B-29D/B-50 program, which arrived too late for World II.

o Other problems arose with defective pressure seals around the cockpit windows and sighting blisters, which needed precise fitting to avoid leakage.

o Also causing problems were the sighting systems (four analog computers) for the remote controlled defensive armament, as well as the turrets themselves.

o Then came electrical failures, caused by faulty Cannon plugs, which supplied connections throughout the ten miles (16 km) of wiring in each B-29.

o Sub-standard glass in the cockpit transparencies meant the pilots had problems due to the distortion.

o A minor "beef-up" was found to be needed on the wing structures

o When General Arnold visited the Wichita Plant on 11 January 1944 he wanted 175 combat ready B-29s for the XX Command. As he was shown around the assembly lines he picked out the 175th fuselage section and signed it commenting: "This is the plane I want. I want it before the First of March. When he discovered two months later that no B-29s were actually combat ready, and that some had been sitting waiting for parts for two months or more Arnold was livid.

o This prompted an intervention by General Hap Arnold to resolve the problem, with production personnel being sent from the factories to the modification centers to speed modification of sufficient aircraft to equip the first Bomb Groups in what became known as the "Battle of Kansas". This resulted in 150 aircraft being modified in the six weeks between 10 March and 15 April 1944. Specialist USAAF ground crew and technicians were called in from all over the country and 600 workers were pulled from the Wichita assembly lines. Subcontractors were told to stop all work on non-B-29 components until they had fulfilled their commitments

o With the thermometer often reading below zero the 1,200 technicians who had gathered at the Wichita factory and the Modification Centers were being asked to modify each bomber inside and out. . Firstly the needed to have some of the plating removed, the required "beef-ups" were added then each piece of skin riveted back in place.

. At the same time the cowl flaps, which controlled airflow through and around the troublesome engines, were being modified.

. Each piece of glass installed in the nose had to be pulled out and replaced with new distortion free panes. After that the pressurization had to be rechecked: 75 B-29s in total needed new glass.

. Internally every electrical plug had to be removed, disassembled and resoldered - a total of 586,000 connections in completed aircraft, plus those on the assembly lines and in wiring harnesses ready for installation.

. A lot of the work was being done in the middle of the frequent snow- storms: it was so cold crews could only work for 20 minutes at a time, with most of the jobs requiring delicate handling

Operational history  In September 1941, the Army Air Forces plans for war against and proposed basing the B-29 in for operations against Germany as British airbases were likely to be overcrowded. planning throughout 1942 and early 1943 continued to have the B-29 deployed initially against Germany, only transferring to the Pacific after the end of the war in Europe.  By the end of 1943, however, plans had changed, partly due to production delays, and the B-29 was dedicated to the Pacific Theater.

Operational history  A new plan implemented at the direction of President Franklin D. Roosevelt as a promise to China, called Operation Matterhorn, deployed the B-29 units to attack Japan from four forward bases in southern China, with five main bases in , and to attack other targets in the region from China and India as needed. Keep China in the war holding down Japanese forces.  The was formed in April 1944 to oversee all B-29 operations. In an unprecedented move, the commander of the USAAF, General Henry H. Arnold, took personal command of this unit and ran it from the Pentagon in Washington, D.C.  If airpower delivers an independent service would be created.  B-29s started to arrive in India in early April 1944. The first B-29 flight to airfields in China (over the , or "") took place on 24 April 1944.  The first B-29 combat mission was flown on 5 June 1944, with 77 out of 98 B-29s launched from India bombing the railroad shops in and elsewhere in .  On 15 June 1944, 68 B-29s took off from bases around , 47 B-29s bombed the Imperial Iron and Steel Works at Yahata, Japan. This was the first attack on Japanese islands since the Doolittle raid in April 1942.The first B-29 combat losses occurred during this raid, with one B-29 destroyed on the ground by Japanese fighters after an emergency landing in China,[44] one lost to anti-aircraft fire over Yawata, and another disappeared after takeoff from Chakulia, India, over the Himalayas This raid, which did little damage to the target, with only one bomb striking the target factory complex, nearly exhausted fuel stocks at the Chengdu B-29 bases  Japan was bombed on: 7 July 1944 (14 B-29s), 29 July (70+), 10 August (24), 20 August (61), 8 September (90), 26 September (83), 25 October (59), 12 November (29), 21 November (61), 19 December (36) and for the last time on 6 January 1945  Brutal Japanese offensive against bases.  -29s were withdrawn from airfields in China by the end of January 1945. Throughout this prior period, B-29 raids were also launched from China and India against many other targets throughout Southeast Asia, including a series of raids on and Thailand.  The B-29 effort was gradually shifted to the new bases in the in the Central Pacific, with the last B-29 combat mission from India flown on 29 March 1945.  Overall, Operation Matterhorn was not successful. The nine raids conducted against Japan via bases in China succeeded only in destroying Ōmura's aircraft factory. XX lost 125 B-29s during all of its operations from bases in India and China, though only 22 or 29 were destroyed by Japanese forces; the majority of the losses were due to flying accidents

Operational history Pacific

 in addition to the logistical problems associated with operations from China, the B-29 could only reach a limited part of Japan while flying from Chinese bases. The solution to this problem was to capture the Mariana Islands, which would bring targets such as , about 1,500 mi (2,400 km) north of the Marianas within range of B-29 attacks. The Joint Chiefs of Staff agreed in December 1943 to seize the Marianas.

 A joint US forces invaded Saipan on 15 June 1944

 Operations followed against Guam and , with all three islands secured by August.

 Naval construction battalions (Seabees) began at once to construct air bases suitable for the B-29, commencing even before the end of ground fighting. In all, five major air fields were built: two on the flat island of Tinian, one on Saipan, and two on Guam. Each was large enough to eventually accommodate a bomb wing consisting of four bomb groups, giving a total of 180 B-29s per airfield.  The first B-29 arrived on Saipan on 12 October 1944, and the first combat mission was launched from there on 28 October 1944, with 14 B-29s attacking the Truk atoll.

 The 73rd Bomb Wing launched the first mission against Japan from bases in the Marianas, on 24 November 1944, sending 111 B-29s to attack Tokyo. For this first attack on the Japanese capital since the Doolittle Raid in April 1942,  Problems with Jetstream, weather fronts, interception, engines affecting bombing accuracy.  In typical American fashion, they found the meanest S.O.B. they could to clean up the G*****M mess.  Japanese cities congested, built of wood, low level industries contribute to war effort.

 In early 1945, Major General Curtis Lemay, commander of XXI Bomber Command, the Marianas-based B-29-equipped bombing force . ordered most of the defensive armament and remote-controlled sighting equipment removed from the B-29s under his command so that they could carry greater fuel and bomb loads as a result of the change of role from high-altitude, daylight bombing with high explosive bombs to low-altitude night raids using incendiary bombs. To maximize the effectiveness of the firebombing attacks, LeMay ordered the B-29s to fly at the low altitude of 5,000 feet (1,500 m) .

 More bombs carried, greater accuracy, less strain on engines.

 With these new tactics, a total of 302 B-29s participated in the Operation Meetinghouse raid on Tokyo on the night of 9–10 March, with 279 arriving over the target. The raid was led by special crews who marked central aiming points. It lasted for two hours. The raid was a success beyond General LeMay's wildest expectations. The individual caused by the bombs joined to create a general , which would have been classified as a but for prevailing winds gusting at 17 to 28 mph (27 to 45 km/h).[4] When it was over, sixteen square miles of the center of Tokyo had gone up in flames and nearly 100,000 people had been killed. Fourteen B-29s were lost. The B-29 was finally beginning to have an effect.

 On the night of 13–14 March, eight square miles of Osaka went up in flames. On 16–17 March, three square miles of were destroyed, and on 19–20 March in a return visit to , three more square miles were destroyed. This destructive week had killed over 120,000 Japanese civilians at the cost of only 20 B-29s lost.  The most commonly cited estimate of Japanese casualties from the raids is 333,000 killed and 473,000 wounded. There are a number of other estimates of total fatalities, however, which range from 241,000 to 900,000. In addition to the loss of mostly civilian life, the raids caused extensive damage.  In Tokyo, Osaka and Nagoya, "the areas leveled (almost 100 square miles (260 km2)) exceeded the areas destroyed in all German cities by both theAmerican and English air forces (approximately 79 square miles (200 km2). 136 B-29s were downed during the campaign to Japan's cities and contributed to a large decline in industrial production.

Name of Japanese Percentage of the Equivalent in size to city firebombed city destroyed the following American city Tokushima 85.2 Ft. Wayne Fukuyama 80.9 Macon Kofu 78.6 South Bend Nara 69.3 Boston Tsu 69.3 Topeka Okayama 68.9 Long Beach Mito 68.9 Pontiac Takamatsu 67.5 Knoxville 66.1 Oklahoma City Tsuruga 65.1 Middleton Nagaoka 64.9 Madison Maebashi 64.2 Wheeling Imabari 63.9 Stockton 63.6 Des Moines Kagoshima 63.4 Richmond Toyohashi 61.9 Tulsa Hamamatsu 60.3 Hartford Isezaki 56.7 Sioux Falls Ichinomiya 56.3 Sprinfield Kobe 55.7 Baltimore Kochi 55.2 Sacramento Kumagaya 55.1 Kenosha Akashi 50.2 Lexington Himeji 49.4 Peoria Hiratsuka 48.4 Battle Creek Tokuyama 48.3 Butte Sakai 48.2 Forth Worth Saga 44.2 Waterloo Chosi 44.2 Wheeling Utsunomiya 43.7 Sioux City Numazu 42.3 Waco Kure 41.9 Toledo Sasebo 41.4 Nashville Uhyamada 41.3 Columbus Ogaki 39.5 Corpus Christi Siumonoseki 37.6 San Diego Kawasaki 36.2 Portland Omuta 35.8 Miami Osaka 35.1 Chicago Yokkichi 33.6 Charlotte Omura 33.1 Sante Fe Okazaki 32.2 Lincoln Kumamoto 31.2 Grand Rapids Oita 28.2 Saint Joseph Miyakonoio 26.5 Greensboro Miyazaki 26.1 Davenport Nobeoka 25.2 Augusta Fukuoka 24.1 Rochester Moh 23.3 Spokane Sendai 21.9 Omaha Yawata 21.2 San Antonio Hbe 20.7 Utica Amagasaki 18.9 Jacksonville Nishinomiya 11.9 Cambridge Toyama 99 Chattanooga Fukui 86 Evansville Kuwana 75 Tucson Hitachi 72 Little Rock Hachioji 65 Galveston Matsuyama 64 Duluth Yokohama 58 Cleveland Tokyo 51 New York Wakayama 50 Salt Lake City Shimizu 42 San Jose Chiba 41 Savannah Nagoya 40 Los Angeles Aomori 30 Montgomery

Operation Starvation  Although less publicly appreciated, the mining of Japanese ports and shipping routes (Operation Starvation) carried out by B-29s from April 1945 significantly affected Japan's ability to support its population and move its troops.  Operation Starvation was an American naval mining operation conducted in World War II by the Army Air Forces, in which vital water routes and ports of Japan were mined by air in order to disrupt enemy shipping.  The mission was initiated at the insistence of Admiral Chester Nimitz who wanted his naval operations augmented by an extensive mining of Japan itself conducted by the air force. LeMay assigned one group of about 160 aircraft of the 313th Bombardment Wing to the task, with orders to plant 2,000 mines in April 1945.  The mining runs were made by individual B-29 Superfortresses at night at moderately low altitudes. Radarprovided mine release information. This mining proved the most efficient means of destroying Japanese shipping during World War II. In terms of damage per unit of cost, it surpassed and the United States submarine campaign.  Eventually most of the major ports and straits of Japan were repeatedly mined, severely disrupting Japanese logistics and troop movements for the remainder of the war with 35 of 47 essential convoy routes having to be abandoned.  For instance, shipping through Kobe declined by 85%, from 320,000 tons in March to only 44,000 tons in July. Operation Starvation sank more ship tonnage in the last six months of the war than the efforts of all other sources combined.  The Twentieth Air Force flew 1,529 sorties and laid 12,135 mines in twenty-six fields on forty-six separate missions. Mining demanded only 5.7% of the XXI Bomber Command's total sorties, and only fifteen B-29s were lost in the effort. In return, mines sank or damaged 670 ships totaling more than 1,250,000 tons.  After the war, the commander of Japan's minesweeping operations noted that he thought this mining campaign could have directly led to the defeat of Japan on its own had it begun earlier. Similar conclusions were reached by American analysts who reported in July 1946 in the United States Strategic Bombing Survey that it would have been more efficient to combine the United States' effective anti-shipping submarine effort with land- and carrier-based air power to strike harder against merchant shipping and begin a more extensive aerial mining campaign earlier in the war. This would have starved Japan, forcing an earlier end to the war. WWII Summary

 The Twentieth Air Force lost 414 B-29s during attacks on Japan

 Much of Japan's industrial capacity was also destroyed by Allied bombing. Over 600 major industrial facilities were destroyed or badly damaged, contributing to a large decline in production

 Approximately 40 percent of the urban area of the 66 cities subjected to area attacks were destroyed ]This included the loss of about 2.5 million housing units, which rendered 8.5 million people homeless.

 To achieve this, the American Twentieth Strategic Air Force, in concert with its Allies, dropped 160,800 tons of bombs on the Japanese home islands. Of this total, 147,000 tons of bombs were dropped by the B-29 bomber force. Around 90 percent of the American tonnage fell in the last five months of the war.

 The financial cost of the campaign to the United States was $4 billion; this expenditure was much lower than the $30 billion spent on bomber operations in Europe, and a small proportion of the $330 billion the US Government spent on the war.

 Japanese payed the price for militarists refusal to surrender.

 Did not talk about atomic bombs, firebombing often overlooked.

UK

American post-war military assistance programs loaned the RAF enough Superfortresses to equip several RAF Bomber Command. The aircraft were known as the Washington B.1 in RAF service, and served from March 1950 until the last bombers were returned in early 1954. 87 loaned from the USAF as the Washington B.1

Soviet re-engineering of the B-29  During 1944 and 1945 five B-29s made emergency landings in Soviet territory after bombing raids on Japanese Manchuria and Japan.  The Tu-4 first flew on 19 May 1947, piloted by test pilot Nikolai Rybko.[19] Serial production started immediately, and the type entered large-scale service in 1949.  Entry into service of the Tu-4 threw the USAF into a panic, since the Tu-4 possessed sufficient range to attack Chicago or Los Angeles on a one-way mission, and this may have informed the maneuvers and air combat practice conducted by US and British air forces in 1948 involving fleets of B-29s.  Eight hundred and forty-seven Tu-4s had been built when production ended in the in 1952, some going to China during the later 1950s and postwar service  Sovet fighters appeared over Korea, and after the loss of 28 aircraft, future B-29 raids were restricted to night-only missions, The B-29 was notable for dropping the large "Razon" and "Tarzon" radio-controlled bomb in Korea, mostly for demolishing major bridges, Boeing B-50 Superfortress  The Boeing B-50 Superfortress is a post–World War II revision of the Boeing B-29 Superfortress, fitted with more powerful Pratt & Whitney R-4360 radial engines, stronger structure, a taller fin, and other improvementsHowever, the later B-50 Superfortress variant (which was initially designated B-29D renamed for congress) was good enough to handle auxiliary roles such as air-sea rescue, electronic intelligence gathering,air-to-air refueling, and weather reconnaissance.  The B-50D was replaced in its primary role during the early 1950s by the Boeing B-47 Stratojet, which in turn was replaced by the Boeing B-52 Stratofortress.  The final active-duty KB-50 and WB-50 variants were phased out in the mid-1960s, with the final example retired in 1965. Seen picture of recon jets refulled on ground in Vietnam.  Boeing built 370 of the various B-50 models and variants between 1947 and 1953.  Lucky Lady II  Lucky Lady II is a Boeing B-50 Superfortress that became the first to circle the worldnonstop when it made the journey in 1949, assisted by in- flight refueling. Total time airborne was 94 hours and 1 minute.  LeMay cited the significance of the mission as indicating that the Air Force now had the capability to take off on bombing missions from anywhere in the United States to "any place in the world that required the atomic bomb"  The aircraft's crew were each awarded the Distinguished Flying Cross and were honoured by the National Aeronautic Association with its annual Mackay Trophy, recognizing the outstanding flight of the year and by the Air Force Association with its Air Age Trophy.  After flying 23,452 mi (37,742 km) he aircraft flew at altitudes between 10,000 to 20,000 ft (3,000 to 6,100 m) and completed the trip around the world at an average ground speed of 249 mph (401 km/h; 216 kn) Boeing C-97 Stratofreighter  The Boeing C-97 Stratofreighter is a long-range heavy military cargo aircraft developed from the B-29 and B-50 bombers. Design work began in 1942, with the prototype's first flight being on 9 November 1944, and the first production aircraft entered service in 1947. followed by its commercial variant, the Boeing Model 377 Stratocruiser in 1947.  . fitting an enlarged upper fuselage onto a lower fuselage and wings which were essentially the same as those of the B-29 Superfortress with the tail, wing, and engine layout being nearly identical.  Between 1947 and 1958, 888 C-97s in several versions were built, 811 being KC- 97 tankers  A heavily modified line of outsized-cargo variants of the Stratocruiser is the Guppy / Mini Guppy /Super Guppy which remain in service today with operators such as NASA.  A transport developed from the B-29 was the Boeing C-97 Stratofreighter, first flown in 1944,  The Boeing 377 Stratocruiser was a large long-range airliner developed from the C-97 Stratofreighter military transport, a derivative of the B-29 Superfortress. The Stratocruiser's first flight was on July 8, 1947.[2] Its design was advanced for its day, its innovative features included two passenger decks and a pressurized cabin, a relatively new feature on transport aircraft. It could carry up to 100 passengers on the main deck plus 14 in the lower deck lounge; typical seating was for 63 or 84 passengers or 28 berthed and five seated passengers.  The Stratocruiser was larger than the Douglas DC-6 and and cost more to buy and operate. Its reliability was poor, chiefly due to problems with the four 28- cylinder Pratt & Whitney Wasp Major radial engines and their four-blade propellers. Only 55 Model 377s were built for , along with the single prototype.  , Inc. is an American aircraft manufacturer which made a name for itself by converting Boeing 377Stratocruisers into the famous Guppy line of , re- engineered solely for transporting oversized cargo such as space exploration vehicles. Survivors  A total of 3,970 B-29s were built.  Twenty-two B-29s are preserved at various museums worldwide, including one flying example; Fifi, which belongs to the Commemorative Air Force, along with four complete airframes either in storage or under restoration (including one to airworthy), eight partial airframes in storage or under restoration, and four known wreck sites.  Important part of aviation history, defence of the west.  Conclude on a lighter note, what we were fighting for…