Date: ca. 1937
Country of Origin: United States of America
3-D Test: 20.3 x 12.7 x 8.9cm (8 x 5 x 3 1/2 in.)
Rods, Chrome-plated steel; cooling jacket, nickel-plated brass; nuts, steel; motor, proper (threaded interior cylinder), non-ferrous metal; retainer rings, steel; hex nut on component No. 3, aluminum; B-nut, brass; nozzle, non-ferrous metal, possibly plated copper or brass; nozzle sleeves or collars (two), brass
This is a replica of the regeneratively-cooled liquid fuel rocket motor designed and built by James H. Wyld of the American Rocket Society (ARS) in 1937.
One major problem faced by early rocket experimenters was overheating of their small motors. Wyld's solution was regenerative-cooling, which was also tried by Robert Goddard and by rocket experimenters in Europe. In this system, the propellant circulates around the motor in a cooling jacket before injection into the combustion chamber where it is ignited with the oxidizer (liquid oxygen). The pre-heated fuel also aids its combustion. The motor was successfully tested in 1938 and 1941.
Wyld and three other ARS members formed Reaction Motors, Inc. (RMI), in December 1941 and this motor is an early replication by the company of that first model, with some of the materials changed. The Reaction Motors Division of Thiokol Chemical Corp. sent the motor to the Smithsonian in 1952.
Gift of Thiokol Chemical Corporation, Reaction Motors Division