This is one of the first successfully flown JATO (Jet-Assisted-Take-Off) rockets in the U.S. It was used on an Ercoupe light aircraft in tests in 1941 at March Field, California. JATOs shortened distances for takeoffs of planes. The motor was designed and made under the GALCIT Rocket Research Project (Guggenheim Aeronautical Laboratory, California Institute of Technology).
The solid propellant JATO produced 28 pounds of thrust for about 12 seconds. Six units were used in each test of the 750 pound plane. The Ercoupe tests led in 1942 to a U.S. Navy contract with GALCIT and the formation of the Aerojet Engineering Company. The Aerojet General Corporation donated this JATO to the Smithsonian in 1968.