Ballistic Research Laboratory

The history of the Ballistic Research Laboratory dates back to World War I with the Office of the Chief of Ordnance (OCO) within the U.S. Army. During the first year of U.S. involvement in the war, the OCO was responsible for supervising ballistic firings at Sandy Hook Proving Ground in New Jersey and computing firing tables for the Army.[4] These firing tables played a vital role in the war effort, because field artillery units heavily relied on them to determine the proper angle of elevation that a specific projectile required to hit a target at a specific range with a given propellant charge. They were also used to predict the projectile's trajectory and correct for variations in atmospheric temperature, air density, wind, and other factors.[5] However, Sandy Hook Proving Ground was closed down in 1917 due to its inadequate size and its close proximity to New York Harbor, and operations were moved to the newly established Aberdeen Proving Ground in Harford County. By early 1918, almost all of the OCO's test firings were conducted at Aberdeen Proving Ground.[4][6]

As the war continued, the Chief of Ordnance created a Ballistics Branch for the OCO on April 6, 1918, to keep up with the rapidly increasing demand for firing tables and other ballistic data.[4] The first Head of the Ballistic Branch was Major Forest Moulton, a former astronomy professor at the University of Chicago. During his tenure as the head of the branch, Moulton significantly expanded the Ballistics Branch, greatly advancing the Army's theoretical and experimental ballistics work as well as recruiting a large number of highly educated scientists to the staff.[4][7]

After the end of World War I, the OCO was reorganized into four major parts in 1919 to accommodate for peacetime operations requirements: the General Office, the Manufacturing Service, the Field Service, and the Technical Staff. In 1935, the Research Division was created at Aberdeen Proving Ground and placed under the control of the Technical Staff. Led by Colonel Hermann H. Zornig, the Research Division initially consisted of only thirty people; however, despite the small staff size, the group supervised six different sections of ballistic work: Interior Ballistics, Exterior Ballistics, Ballistics Measurements, Ordnance Engineering, Computing, and War Reserve. The Internal Ballistics Section was responsible for mathematical and experimental research that advanced the theory of interior ballistics and the investigation of gun design principles. It also conducted effect-of-fire investigations, which studied the behavior of projectiles and bombs as well as their individual components as they approached a target. The Exterior Ballistics Section focused on the trajectories and flight characteristics of projectiles and bombs, which influenced the design of new munitions. The Ballistics Measurements Section developed improved ballistic measuring devices, while the Ordnance Engineering Section made kinematic and mechanical analyses of gun mechanisms and gun mounts. The Computing Section was tasked with preparing firing and bombing tables for standard ammunition and bombs, and the War Reserve Section was responsible for the surveillance of stored ammunition.[4]

In 1938, the Research Division was renamed the Ballistic Research Laboratory and Colonel Zornig became its first director.[8] This development was made largely in recognition of the Research Division's importance to the U.S. Army, and, in 1939, the Army Air Corps contributed funds to BRL for a new building to house additional laboratory facilities as a show of gratitude for the lab's work on bomb ballistics. As a result of the change, the Interior Ballistics Section was broken down into Mathematical (transferred to the Exterior Ballistics Section), Mechanics and Heat, Physical Chemistry, and Effect of Fire Units, while the Computing Section was divided into Ground Gunfire, Bombing, and Air Gunfire Units.[4]

The Ballistics Research Laboratory further expanded its capabilities and quickly rose to prominence during the timespan of World War II. Compared to its initial staff of 65 people with a $120,000 annual budget in 1940, BRL grew to have over 700 personnel with an annual budget of $1.6 million by 1945.[4] It was responsible for conducting basic and technical research in ballistics and other related scientific fields as well as overseeing the development of computing techniques, the preparation of ballistic tables for guns, bombs, and rockets, and the provision of information regarding the use of various weapons during combat.[9] Unlike civilian laboratories whose productions were inherently restricted by anticipations of market demand, BRL owned a significant portion of its success to how the development of their instruments and technologies reflected only what the Army needed. Enough flexibility was provided to the lab so that it could improvise solutions to particular problems and later refine those improvisations for wider use.[4]

In 1940, Zornig established a Scientific Advisory Council, with which he appointed eminent American scientists and engineers to undertake various assignments for BRL.[10] The original members of the committee consisted of aerodynamicist Hugh Dryden, physicist Albert Hull, physical chemist Bernard Lewis, astronomer Henry Russell, physicist Isidor Rabi, physical chemist Harold Urey, aerospace engineer Theodore von Karman, and mathematician John von Neumann.[8]

For the majority of the war, a substantial amount of the BRL effort was directed toward testing weapons and computing firing and bombing tables. However, the lab was also involved in significantly improving the quality control of stockpiled ammunition as well as training and deploying technical service teams to calibrate guns on the battlefield. In addition, BRL provided technical analysis assistance to the U.S. Army and Army Air Forces, such as determining the optimum bomb pattern for bombing runs, improving the accuracy of aerial gunnery, and conducting studies on the vulnerability of the German 88-mm gun to fragmenting shells.[9] In August 1943, Ordnance Department Order 80 designated the BRL as the principal research organization of the U.S. Army's Ordnance Department.[4]

One of the major events that took place at BRL during the war was the installation of the first supersonic wind tunnel in the United States. The recommendation to construct a wind tunnel at Aberdeen Proving Ground was made in 1940 by Theodore von Karman, a member of the Scientific Advisory Committee. Karman proposed that a wind tunnel would greatly enhance ballistic research since it could produce both subsonic and supersonic velocities. Soon afterwards, the Guggenheim Aeronautical Laboratory of the California Institute of Technology was commissioned with designing a wind tunnel that could produce velocities up to Mach 4.3. However, the wind tunnel was not constructed until the fall of 1943 and was not ready for use until November 1944.[4] Upon its completion, Edwin Hubble, the Chief of the External Ballistics Branch, was arranged as the first head of the Supersonic Wind Tunnel with BRL Assistant Director Robert Kent assigned as the second head.[11] The wind tunnel was primarily used to obtain basic design information for the development and modification of bombs, rockets, and other fin-stabilized projectiles.[4]

Near the end of World War II, BRL also conducted a series of experiments assessing the vulnerability and survivability of U.S. Army aircraft.[9]

During the interwar period between the First and Second World War, the need for a faster and more efficient method of constructing artillery firing tables prompted BRL to consider the potential applications of digital computation.[4] In 1935, before the Research Division became BRL, the Technical Staff acquired a copy of the Bush differential analyzer, which could compute a 60-second trajectory in about 15 minutes compared to about 20 hours performed by a person with a desk calculator.[5] However, even the differential analyzer was not enough to keep up with the needs of the U.S. Army.[4] By 1941, the production of firing tables was so far behind that BRL rushed to find any means of expediting the ballistic computation process.[5] To ease the burden of work, the lab trained almost 100 female graduates from colleges all over the Northeast to calculate ballistic firing tables. When the Women's Army Corps was formed, those assigned to ballistic computation were trained in Philadelphia and deployed to Aberdeen Proving Ground.[12] During this time, Colonel Paul Gillon of the OCO had his attention on the Moore School of Electrical Engineering at the University of Pennsylvania. Gillon, who oversaw the ballistic computations needed for the firing and bombing tables, knew that an upgraded version of the Bush differential analyzer existed at the Moore School.[13]

In 1942, John Mauchly and John Presper Eckert at the Moore School submitted a proposal to the Ballistic Research Laboratory that detailed the creation of a high-speed computation device for computing ballistic trajectories.[14] On June 5, 1943, the Army Ordnance Corps and the University of Pennsylvania signed a six-month contract in the amount of $61,700 (equivalent to $1,043,442 in 2022) for the construction of the Electronic Numerical Integrator and Computer, or ENIAC.[5]

Known as “Project PX,” the secret construction of the pilot model took place at the Moore School with Eckert as chief engineer and Mauchly as principal consultant.[3] However, building the ENIAC proved to be more arduous than expected. By 1944, only two of the four accumulators were completed. At this point, BRL had only fallen further behind the demand for firing tables. While the number of table requests reached forty a week, BRL could only produce about fifteen. But despite the slow progress, the finished accumulators performed twice as fast as the initial stipulated speed, operating at 200,000 pulses a second. Impressed by this demonstration, BRL agreed to increase the number of accumulators in the ENIAC from four to twenty, delaying its completion even further but obtaining a much more powerful machine in exchange. As a result, the ENIAC wasn't finished until November 1945, three months after the end of the war.[15] Throughout the course of ENIAC's construction, nine additional supplements were made to the initial contract, increasing the Project PX's overall cost to $486,800 (equivalent to $7,912,974 in 2022).[5]

While ENIAC never saw use during World War II, its first job upon completion was to calculate the feasibility of a proposed design for the hydrogen bomb.[16] But while ENIAC could perform ballistic calculations at impressive speeds, it was held back by its lack of internally stored program capability.[17] It took scientists a month to complete the calculation due to the thousands of steps involved as well as ENIAC's inability to store programs or remember more than twenty ten-digit numbers. Nevertheless, the electronic computer revealed several flaws in the proposed design of the bomb that would have been nearly impossible to identify otherwise.[16] The formal dedication of the ENIAC took place on February 15, 1946, at the Moore School, and the machine was moved to its permanent home at Aberdeen Proving Ground in January 1947.[18] During a formal demonstration of the ENIAC in 1946, the Army showed the machine could solve 5,000 addition problems in one second as well as 50 multiplication problems in one second.[19] While the Bush differential analyzer could compute a 60-second trajectory in about 15 minutes, the ENIAC could do the same in about 30 seconds.[5] In 1948, BRL converted ENIAC into an internally stored-fixed program computer and used it to perform calculations on not just ballistics but also for weather prediction, cosmic ray studies, thermal ignition, and other scientific tasks. In addition, it was also made available to universities free of charge.[3]

But even before ENIAC was operational, BRL had already started to plan for the development of a stored-program computer known as the Electronic Discrete Variable Computer, or EDVAC. In 1944, in the middle of ENIAC's development, Mauchley and Eckert proposed the creation of EDVAC to make up for ENIAC's shortcomings. Unlike its predecessor, the EDVAC was planned to have a central processor and a memory for both data and programs.[20] During this time, John von Neumann became involved in the work on both ENIAC and EDVAC and was among those who supported funding the EDVAC project. In October 1944, the Ordnance Department issued a contract and $105,600 (equivalent to $1,755,475 in 2022) in funding for the development of this new machine with supervision of the project assigned to BRL.[3] Built as a collaborative effort between BRL, the Moore School, the Institute for Advanced Studies, and the National Bureau of Standards, EDVAC was completed and installed at BRL in 1949. However, it wasn't operational until 1952 due to design issues. By then, BRL had already acquired the Ordnance Discrete Variable Automatic Computer (ORDVAC), which the lab had commissioned the University of Illinois to build. As a result, BRL was the world's largest computer center for a brief time in 1952 with ENIAC, EDVAC, and ORVAC all in its possession.[5]

After World War II, the six branches at BRL were raised to laboratory status in August 1945, leading to the formation of the Interior Ballistics Laboratory, the Exterior Ballistics Laboratory, the Terminal Ballistics Laboratory, the Ordnance Engineering Laboratory, the Ballistic Measurements Laboratory, and the Computing Laboratory.[4] These six labs were collectively referred to as the Ballistic Research Laboratories.[11] In 1953, BRL replaced the Ordnance Engineering Laboratory with another laboratory called the Weapons Systems Laboratory to increase research in weapon effectiveness and vulnerability assessment.[21] The post-war era also saw BRL administer more of its research through private contractors and other government agencies. About 25 percent of the total appropriation for research from 1953 to 1956 was channeled in this way.[4] In 1958, BRL established the Future Weapons System Agency to provide an unbiased source of advice on new weapon development programs to the Ordnance Corps.[21]

Throughout the 1960s and 1970s, BRL increased its focus on target acquisition, guidance, and control technology and expanded its research to include more sophisticated weapon systems. At the same time, the lab discontinued research for which the technology had sufficiently matured and transferred much of its routine or service operations to other agencies. This transition included the transfer of its Pulse Radiation Facility to the Army Test and Evaluation Command, the transfer of the Tandem Van de Graaff Accelerator to the University of Pennsylvania, and the closure of the BRL wind tunnels. In 1962, as part of the Army's major reorganization effort, BRL was placed under the new U.S. Army Materiel Command (AMC) alongside other groups such as the Harry Diamond Laboratory and the Human Engineering Laboratories. But unlike the other organizations at Aberdeen Proving Ground, BRL was classified as a Class II Activity, which made it separate from the administration of the Aberdeen Proving Ground Command and allowed BRL to receive funds directly from AMC.[21]

As Army leaders continued to streamline the research labs in an effort to eliminate overlapping functions, the Ballistic Research Laboratories underwent several organizational changes. In 1968, BRL's Ballistic Measurements Laboratory became the Signature and Propagation Laboratory, which remained under BRL. In 1969, the Ballistic Research Laboratories added yet another laboratory called the Nuclear Defense Laboratory, which was renamed as the Nuclear Effects Laboratory upon consolidation. In the early 1970s, BRL replaced its Signature and Propagation Laboratory with the newly formed Concepts Analysis Laboratory and replaced its Nuclear Effects Laboratory with the Radiation Laboratory. Finally, in 1976, the Ballistic Research Laboratories merged all of the existing laboratories under its command and to become the new Ballistic Research Laboratory once more. As a result, the seven laboratories were turned into six new divisions: the Interior Ballistics Division, the Launch and Flight Division, the Terminal Ballistics Division, the Ballistic Modeling Division, the Vulnerability Analysis Division, and the Computer Support Division.[21]

In 1992, the Ballistic Research Laboratory was one of the seven Army laboratories that was consolidated to form the U.S. Army Research Laboratory. Its operations were divided into three parts, each of which merged into different ARL directorates. The bulk of BRL formed the core of the Weapons Technology Directorate, which later became the Weapons and Materials Research Directorate. BRL's computer technology elements migrated to the Advanced Computational and Information Sciences Directorate, which later became the Computational and Information Sciences Directorate. Lastly, BRL's vulnerability analysis component became a part of ARL's Survivability/Lethality Analysis Directorate.[2]

As high-speed computation became a major Army priority, BRL played a major role in the development of the modern computer as the lab worked to increase the pace of military calculations. In addition to aiding the development of some of the world's earliest electronic computers, BRL focused on making advancements in both hardware and software with an emphasis on augmenting the speed of operation, ease of programming, and overall economy of their computers.[4] After the successful demonstration of its early electronic computers, BRL continued to invest heavily in high speed computation research. In 1956, researchers at BRL began developing a new computer on their own called the Ballistic Research Laboratories Electronic Scientific Computer, or BRLESC. Completed in 1961, it was very briefly considered the world's fastest computer before it was quickly outperformed by the IBM 7030 Stretch. In 1967, BRL developed a solid-state digital computer called the BRLESC II, which was designed to run 200 times faster than the ORDVAC. BRLESC I and II became the last computers designed and developed by BRL. After performing around-the-clock operations for more than a decade, both the BRLESC I and II were shut down in 1978. Despite this, BRL continued to conduct research on high-speed computing and was involved in the development of new hardware and software such as the Heterogeneous Element Processor and ping.[5]

Interior ballistics research at BRL focused primarily on improving the propulsion of munitions and increasing the speed of Army missiles. In working toward this goal, BRL developed new propellants that provided more power and energy while maintaining stability and control.[25] Such work entailed analyzing the chemistry of flames, the mechanics of the launching process, and the propellants’ physical and chemical properties. More specific objectives that the researchers word toward included increased muzzle velocity, better burning of propellants, the elimination of hang fires, the reduction of bore erosion, the reduction of muzzle flash and smoke, decreased gun weight, and better recoil mechanisms. Early in its history, BRL's two principal objectives were to learn more about the fundamental processes of interior ballistics to design better guns and to develop more accurate methods of predicting how those guns would perform. This meant that many of the studies that the lab conducted concentrated on issues surrounding how the propellant interacted with the munition. BRL researchers also focused heavily on the physical chemistry of the propellants as well as the thermodynamic qualities of the powder gases produced from burning the propellant. BRL research in interior ballistics led to a wider range of propellants for different weapon systems that achieved higher velocities.[4] As artillery technology became more sophisticated, BRL used its electronic computers to develop digital programs that simulated the interior ballistic performance of its weapon systems. Interior ballistic data from gun firings also helped BRL researchers create models to guide the design of future munitions. By the mid-20th century, the lab had started developing propellants for advanced rockets and large caliber ammunition. Researchers were also engaged in studies pertaining to ignition, combustion, weapon kinematics, and gun barrel erosion.[21]

Exterior ballistics research at BRL focused on the outward design of Army missiles and the aerodynamic phenomena that influence their flight. In addition to known forces such as drag and lift, BRL researchers were tasked with analyzing potential factors that could influence a projectile's behavior such as the effects of the Magnus force and moment. Both theoretical and experimental studies helped BRL researchers create new techniques for designing aerodynamically stable missiles. One of the most important tasks that BRL performed was developing techniques for predicting the dynamic stability of proposed spin-stabilized missile designs. However, researchers also analyzed designs for fin-stabilized projectiles as well. Other areas of research included analysis on boundary layers, heating rates, and the chemical interactions between the travelling projectile and the surrounding air and electric fields.[4][25] BRL's exterior ballistics division was not solely responsible for developing better projectiles and firing techniques. This section of the lab was also in charge of preparing the firing and bombing tables for soldiers in the field. During World War II, weapon accuracy became a critical focal point for BRL researchers, who directed much of their wartime effort toward refining the ballistic performance of the projectiles. In order to test the performance of different projectiles under various conditions, the lab relied heavily on the supersonic wind tunnels and aerodynamic ranges installed at Aberdeen Proving Ground. The wind tunnels were used extensively during the late 1950s for BRL's cross-wind program, which arose from the Army's need to obtain aerodynamic data in order to prepare firing tables for aircraft rounds fired at large initial yaw angles.[4] During the Space Race, BRL assisted in the development of several spacecraft, including the Mercury, Gemini, and Apollo Projects. The lab also engaged in research regarding high altitude atmospheric physics research, fluid physics, and experimental aeroballistics as well as the development of intercontinental ballistic missiles.[21]

Terminal ballistics research at BRL studied the underlying effects of weapons upon striking their target. BRL researchers in this field conducted experimental and theoretical work on the impact behavior of projectiles and investigated topics such as the mechanisms of penetration, fragmentation, wound ballistics, detonation, shockwave propagation, and combustion.[25] During the post-World War II era in particular, BRL intensified its terminal ballistics research in response to the Army's need for more destructive weapon systems with greater firepower and the rapid advancement of instruments that could provide more precise data about a weapon's terminal effectiveness. This division of the lab also focused on investigating nuclear physics and participated in nuclear blast field tests. BRL developed and provided all instrumentation for measuring air blasts, shock velocities, and hydrostatic pressures for Operation Buster-Jangle and Operation Tumbler-Snapper in 1952, Operation Upshot-Knothole in 1953, Operation Castle in 1954, and Operation Teapot in 1955.[4] The laboratory also conducted air blast research during Operation Blowdown in 1963 and Operation Distant Plain in 1966 and 1967. In addition, a large portion of the basic research was directed toward the development of predictive mathematical models and computer programs. While terminal ballistics played a large role in weapon design and evaluation, BRL used the experimental data to develop protective technologies as well, including various kinds of tank armor. The lab also conducted research into the effects of laser beams starting in the 1960s.[21]

Around the end of World War II, BRL was assigned by the Office of the Chief of Ordnance to conduct vulnerability analysis of combat aircraft and munitions and to implement plans to reduce those vulnerabilities. Over time, BRL expanded this role to evaluate all types of weapon systems and vehicles and applied their findings to improve future designs. The laboratory not only conducted vulnerability analysis on American weapon systems to enhance their performance, but it also analyzed enemy combat systems to pinpoint their weaknesses. While this was a relatively small duty compared to some of its other functions, vulnerability analysis and reduction nevertheless became the central focus for an entire division within BRL as researchers conducted studies concerning methods to increase the effectiveness of Army technology. Throughout the Vietnam War, BRL researchers were tasked with continually analyzing combat damage to U.S. aircraft. The laboratory also tested nuclear weapons effects on aerial vehicles and missiles by using high explosive charges to simulate the blast from a nuclear weapon. In general, BRL functioned as the Army's lead laboratory in vulnerability analysis in regards to combat and other external damage, whereas the Army's Vulnerability Assessment Laboratory conducted vulnerability analysis in regards to electronic warfare susceptibility.[21]

Weapon systems research at BRL generally referred to the study of various munitions from an operational analysis viewpoint. These studies focused on enhancing the effectiveness of various weapons such as guns and rockets against a wide variety of targets from personnel to armed tanks. This research was primarily done to assess and predict how each weapon system would perform in a given situation.[25] Beginning in the early 1950s, BRL relied on operations research techniques to evaluate both the weapon systems and the experimental approach with which they were evaluated. The lab also incorporated concepts from game theory to develop programs that simulated battles that allowed them to analyze different tactics and the use of particular weapons in certain situations. Data collected from these studies, largely with the assistance of BRL's electronic computers, helped guide weapon development for the Army as BRL researchers formulated which weapon system performed best against specific targets under various circumstances. After 1968, the focus of weapon systems research shifted to developing new technical approaches to solving Army problems. BRL researchers also planned for the possibility of total nuclear war and thus focused heavily on evaluating intercontinental ballistic missiles, air defense platforms, and advanced submarine systems. BRL also conducted numerous studies that took factors such as cost-effectiveness and ammunition availability into consideration.[21]