WAC Corporal

WAC Corporal. The WAC Corporal was the United States' first successful sounding rocket and a foundational vehicle in the development of American rocketry. Developed by the Jet Propulsion Laboratory and built by the Douglas Aircraft Company, it was designed to carry scientific instruments into the upper atmosphere. Its successful flights at White Sands Proving Ground provided critical data and experience that directly influenced later missile and space programs.

Development and design

The project was initiated under the direction of the California Institute of Technology and the United States Army's Ordnance Corps, with key figures like Frank Malina and Theodore von Kármán leading the design team at the Jet Propulsion Laboratory. The rocket's name was derived from the Women's Army Corps, a nod to its smaller size compared to the larger V-2 rocket being tested concurrently. Its airframe was constructed from lightweight aluminum, and it utilized a pioneering liquid-propellant engine developed by Aerojet, burning a hypergolic mixture of red fuming nitric acid and aniline. For initial launch, it was mounted on a rail and used a separate solid-propellant booster, also built by Aerojet, to achieve sufficient velocity before the sustainer engine ignited.

Operational history

The first successful launch occurred on September 26, 1945, at White Sands Proving Ground in New Mexico, reaching an altitude of approximately 70 kilometers. This and subsequent flights were part of Project Hermes, which also involved testing captured German V-2 rockets, and the WAC Corporal was sometimes used as a second stage in these experiments. In a famous 1949 mission known as Bumper-WAC, a WAC Corporal mounted atop a V-2 became the first two-stage rocket launched from Cape Canaveral, achieving a record altitude. Over its operational life from 1945 to 1951, the rocket conducted sixteen launches, with fourteen successes, gathering valuable data on upper atmosphere conditions, cosmic rays, and wind shear.

Technical specifications

The WAC Corporal stood 4.9 meters tall with a diameter of 0.30 meters and had a launch mass of about 300 kilograms. Its liquid-propellant sustainer engine, produced by Aerojet, generated 6.7 kilonewtons of thrust using the hypergolic propellants red fuming nitric acid and aniline. The initial booster was a solid-fuel motor that provided a short, high-thrust impulse. The rocket could carry a small payload of scientific instruments, approximately 11 kilograms, to altitudes exceeding 80 kilometers, crossing the recognized boundary of space. Its guidance was minimal, relying on a preset trajectory stabilized by fins, with no active control system after launch.

Legacy and impact

The WAC Corporal proved the viability of American-designed liquid-fuel rockets and established critical operational procedures at White Sands Proving Ground. Its technology and engineering team directly contributed to the development of the Corporal missile, the United States' first nuclear-armed surface-to-surface missile. The experience gained, particularly from the Bumper-WAC flights, provided foundational knowledge for multi-stage rocketry that would be essential for later programs like the Redstone and ultimately the Saturn V. As a pioneering sounding rocket, it demonstrated the practical use of rockets for peaceful scientific exploration, setting a precedent for organizations like NASA and influencing the design of subsequent research vehicles such as the Aerobee.

Category:Sounding rockets of the United States Category:1945 in spaceflight