EYES AND EARS: A HISTORY OF FIELD ARTILLERY TARGET ACQUISITION BY BOYD L. DASTRUP, PH.D. HISTORIAN U.S. ARMY FIELD ARTILLERY SCHOOL FORT SILL, OKLAHOMA 2018 INTRODUCTION The conversion from direct fire to indirect fire at the beginning of the 20th Century dramatically changed field artillery target acquisition. Employing direct fire, cannoneers positioned their field pieces unprotected in the open at close ranges to see their enemy easily, to acquire their own targets, and to adjust their own fire. Prompted by rifled small arms and rifled field artillery fire during the Franco-Prussian War of 1870-1871 that annihilated the combatants’ field batteries sited in the open for direct fire, European field artillerymen slowly changed their tactics during the ensuing years. To protect their guns they decided to conceal them behind natural or artificial obstacles where the battery gun crew could not see the target without assistance; and this compounded a growing problem. By the 1870s the average European and American rifled field piece had a range of 4,000 yards and therefore could shoot considerably farther than the human eye could see even with binoculars. Unless armies could find a method of locating targets beyond the range of human eyesight, hiding field artillery behind an obstacle of some kind for protection and employing long-range field artillery would be problematic. Indirect fire offered the solution. It permitted gun crews to hide their cannons for protection and simultaneously engage targets that could not be seen from the battery position. Although various methods of indirect fire had been employed for some years in Europe, they were more suited to siege warfare than mobile warfare. With this in mind, Lieutenant Colonel Karl Guk of the Russian army developed the most practical indirect fire method for a mobile battlefield. Introduced early in the 1880s, Guk’s concept of indirect fire involved using a forward observer, a compass, and an aiming point to hit targets beyond the sight of the battery. However, the reluctance to abandon tried and proven direct fire that was the prevailing gunnery technique where the gunner had to have a direct line of sight from the gun to the target slowed down adopting Guk’s method or any other form of indirect fire for that matter. The Japanese army’s employment of indirect fire crushed Russian field artillery positioned in the open for direct fire at the Battle of Sha Ho in the fall of 1904 and subsequent effective use of indirect fire during the rest of the Russo-Japanese War of 1904- 1905 convinced the Europeans and Americans to abandon direct fire for indirect fire. Notwithstanding the Russian disaster, the Europeans and Americans still clung to direct fire as an alternative to indirect fire. As late as 1914, they still taught their gun crews to abandon indirect fire during the last stages of the attack. They had to move their guns out into the open, move within them with small arms range, and employ direct fire to help press home the infantry attack. Ultimately, World War One forced armies to adopt indirect fire without qualifications. As anticipated by advocates, indirect fire profoundly transformed field artillery target acquisition. Unable to see the battlefield from their concealed positions on the reverse side of a slope, European and American field artillerymen initially turned to terrestrial forward observers to obtain targets and adjust fire. Positioned where they could see the targets, forward observers became the eyes of the Field Artillery; but they could not see targets beyond the horizon. Battlefield conditions during World War One quickly led to the introduction of more sophisticated means of target acquisition to overcome this inherent limitation of terrestrial ii observation. Needing to locate deeply defiladed enemy batteries and other positions beyond the view of terrestrial forward observers, the combatants sent observers aloft in balloons and fixed-wing aircraft. Although aerial observation enabled seeing beyond the visible horizon and finding defiladed batteries and enemy positions, it forced armies to camouflage their positions to avoid detection by aerial observers. In response to this development, the combatant armies introduced sound ranging and flash ranging to find camouflaged targets that could not be spotted by terrestrial and aerial observers. As the evolution of target acquisition during the war suggested, the American Expeditionary Force (AEF) not only imitated its European counterparts but also improvised to satisfy immediate needs. Influenced by the Europeans’ success with sound ranging, flash ranging, and aerial observation in 1914-1917, the Americans adopted them without reservation but interestingly failed to give the Field Artillery any command and control over those assets. The AEF placed sound ranging and flash ranging under the Corps of Engineers where the expertise for such technology resided. However, engineers had little understanding of field artillery requirements and had difficulties meeting the Field Artillery’s needs. At the same time the AEF positioned aerial observation under the Air Service in the Signal Corps that had the aircraft and pilots and often had conflicting priorities with the Field Artillery. This arrangement for the command and control of sound ranging, flash ranging, and aerial observation created unwieldy coordination problems and left the Field Artillery at the mercy of other branches when terrestrial observation was inadequate. Although target acquisition organization was restructured between 1919 and 1942 to furnish the Field Artillery with organic sound ranging, flash ranging, and aerial observation, elusive mortars in World War Two brought further changes. Improvising once again to meet an unforeseen need, the American army modified antiaircraft radars to find ground targets, especially mortars, and attached them to sound ranging and flash ranging units. At the end of the war, American field artillery target acquisition consisted of terrestrial observers, aerial observers, sound ranging, flash ranging, and radars. These methods of organic target acquisition remained unchanged until the 1980s when organic aerial observation disappeared with the creation of centralized aviation in the division and when sound ranging and flash ranging with their range limitations were eliminated in favor of radars to complement terrestrial observation. With the introduction of precision munitions late in the 20th Century, the Field Artillery adopted target location sensors for the mounted and dismounted forces to pinpoint targets accurately and to complement radars and terrestrial observers. This monograph that was initially written in 2008 and revised in 2018 tells the story of the evolution of U.S. Army’s field artillery target acquisition from direct fire to indirect fire. It describes the challenges to create target acquisition capabilities to satisfy the requirements of the Field Artillery and the debates over technology, organization, and doctrine. Boyd L. Dastrup, Ph.D. Field Artillery School Historian U.S. Army Field Artillery School iii LIST OF ACCRONYMS ACH, Annual Command History AEF, American Expeditionary Force AHIP, Army Helicopter Improvement Program AHR, Annual Historical Review AIS, Artillery Intelligence Service ATACMS, Army Tactical Missile System ATACS, Artillery Target Acquisition Counterfire System BFIST, Bradley Fire Support Team COLT, Combat Observation Lasing Team CRAM, Counter Rocket, Artillery, Mortar CSSG, Close Support Study Group FADAC, Field Artillery Digital Artillery Computer FCoE, Fires Center of Excellence FIST, Fire Support Team FSCOORD, Fire Support Coordinator G/VLLD, Ground/Vehicular Laser Locator Designator HMMWV, High Mobility Multipurpose Wheeled Vehicle HRDC, Historical Research and Document Collection JETS, Joint Effects Targeting System FIST, Fire Support Team FS3, Fire Support Sensor System LLDR, Lightweight Laser Designator Radar LCMR, Lightweight Countermortar Radar LRAS3, Long-Range Advance Scout Surveillance System LST, Landing Ship Tank MLRS, Multiple Launch Rocket System MSTL, Morris Swett Technical Library NATO, North Atlantic Treaty Organization ODS, Operation Desert Storm OEF, Operation Enduring Freedom, Afghanistan OIF, Operation Iraqi Freedom PFED, Pocked-size Forward Entry Device QRC, Quick Response/Reaction Capability RPV, Remotely Piloted Vehicle TRADOC, U.S. Army Training and Doctrine Command UAV, Unmanned Aerial Vehicle USAFACFS, U.S. Army Field Artillery Center and Fort Sill USAFAS, U.S. Army Field Artillery School USAFCoE, U.S. Army Fires Center of Excellence USAREUR, U.S. Army, Europe USFET, U.S. Forces, European Theater iv WD, War Department v TABLE OF CONTENTS Title Page i Introduction ii List of Acronyms iv Table of Contents vi Chapter One, Transformation of the Field Artillery 1 Chapter Two, Consolidating and Proving 30 Chapter Three, Falling Behind 75 Chapter Four, Halting the Slide 102 Chapter Five, The Precision Revolution and Target Acquisition 137 Select Bibliography 160 Index 175 Photographs, pp. 67, 68, 69, 70, 71, 72, 73, 74, 136, and 159 vi CHAPTER ONE TRANSFORMATION OF THE FIELD ARTILLERY The Industrial Revolution of the 18th and 19th Centuries with its rapid technological advances dramatically modified all aspects of European and American life. The revolution mechanized tedious, labor-intensive agricultural and industrial processes, made mass production of standardized parts possible, and dramatically improved communications to make the world smaller.