The Ballistic Research Laboratory (BRL) was a research facility under the U.S. Army Ordnance Corps and later the U.S. Army Materiel Command that specialized in ballistics as well as vulnerability and lethality analysis. Situated at Aberdeen Proving Ground, Maryland, BRL served as a major Army center for research and development in technologies related to weapon phenomena, armor, accelerator physics, and high-speed computing. In 1992, BRL was disestablished, and its mission, personnel, and facilities were incorporated into the newly created U.S. Army Research Laboratory (ARL).
The laboratory is perhaps best known for commissioning the creation of the Electronic Numerical Integrator and Computer (ENIAC), the first electronic general-purpose digital computer.
History Formation 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, OCO was responsible for supervising ballistic firings at Sandy Hook Proving Ground in New Jersey and computing firing tables for the Army. 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. However, Sandy Hook Proving Ground was closed down in 1917 due to its inadequate size and its close proximity to New York Harbor. Operations were subsequently moved to the newly established Aberdeen Proving Ground in Harford County. By early 1918, almost all of OCO's test firings were conducted at Aberdeen Proving Ground.
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. Major Forest Moulton, a former astronomy professor at the University of Chicago, served as the first head of the Ballistics Branch. During his tenure, Moulton revamped how the branch conducted its ballistics work and recruited a large number of highly educated scientists to expand the staff.
In 1919, the OCO was reorganized into four major parts—the General Office, the Manufacturing Service, the Field Service, and the Technical Staff—in accordance with peacetime operations requirements. 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 30 people. Despite the small staff size, however, 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. 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 performed 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.
In 1938, the Research Division was renamed the Ballistic Research Laboratory in order to give greater emphasis to the organization’s basic mission, and Colonel Zornig became its first director; the assistant director was Captain Leslie E. Simon. The following year, 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. This building was designated as Building 328 and was completed in 1941. World War II The Ballistics Research Laboratory further expanded its capabilities and quickly rose to prominence during the timespan of World War II; in 1941 Simon replaced Zornig as director. 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. 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, and the provision of information regarding various weapon effects. Unlike civilian laboratories whose productions were inherently restricted by anticipations of market demand, BRL owed 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 laboratory so that it could improvise solutions to particular problems and later refine those improvisations for wider use.
In 1940, Zornig established a Scientific Advisory Council and appointed eminent American scientists and engineers to undertake various assignments for BRL. 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.
For most of the war, a substantial amount of the BRL effort was directed toward testing weapons and computing firing and bombing tables. However, the laboratory 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. Near the end of the war, BRL also conducted a series of experiments assessing the vulnerability and survivability of U.S. Army aircraft. In August 1943, Ordnance Department Order 80 designated the BRL as the principal research organization of the U.S. Army's Ordnance Department.
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. 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. The wind tunnel was primarily used to obtain basic design information for the development and modification of bombs, rockets, and other fin-stabilized projectiles.
In 1943, the Ballistic Research Laboratory quietly initiated Project ALECTO, an experimental effort to simulate the effects of high-explosive blasts on armored vehicles using analog computing methods. Named after one of the Greek Furies, ALECTO used a combination of scaled physical models, high-speed photography, and a modified Bush differential analyzer to predict structural deformation under blast pressure. While rudimentary by modern standards, ALECTO marked one of the first attempts to blend experimental and computational modeling for battlefield survivability analysis. Findings from Project ALECTO directly informed postwar armor design protocols and laid conceptual groundwork for BRL’s later digital simulation programs in the 1960s.Mallory, R.C. Pre-Digital Simulation Initiatives at the U.S. Army Ballistic Research Laboratory, 1942–1950. U.S. Army Technical Archives, Monograph Series 11-B, 1978, pp. 47–58.
Development of electronic computers
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. 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. However, even the differential analyzer was not enough to keep up with the needs of the U.S. Army. By 1941, the production of firing tables was so far behind that BRL rushed to find any means of expediting the ballistic computation process. To ease the burden of work, the laboratory 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. 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.
In 1942, John Mauchly and John Presper Eckert at the Moore School submitted a proposal to BRL that detailed the creation of a high-speed computation device for computing ballistic trajectories. On June 5, 1943, the Army Ordnance Corps and the University of Pennsylvania signed a six-month contract in the amount of $61,700 for the construction of the Electronic Numerical Integrator and Computer, or ENIAC.
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. However, building ENIAC proved to be more arduous than expected. By 1944, only two of the four accumulators were completed. Meanwhile, BRL had only fallen further behind the demand for firing tables. Although the number of table requests reached 40 a week, BRL could only produce about 15. 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 ENIAC from four to twenty, delaying its completion even further but obtaining a much more powerful machine in exchange. As a result, ENIAC wasn't finished until November 1945, three months after the end of the war. Throughout the course of ENIAC's construction, nine additional supplements were made to the initial contract, increasing Project PX's overall cost to $486,800.