This object is part of the American Rocket Society's (ARS) second and last motor to fly. It was used in the flight of ARS Rocket No. 4 on 9 September 1934 at Marine Park, Great Kills, Staten Island, New York. The rocket went up to 116 m (382 ft) and landed 408 m (1,338 ft) away. It flew about 1500 km/h (600 miles an hour).
The motor, which burned gasoline and liquid oxygen, originally had four canted exhaust nozzles facing outward, but during the flight one of the nozzles burned out and was lost while another nozzle was removed for an examination of the rocket and not replaced. The specimen therefore only has two of the remaining nozzles. After this flight, the ARS members decided to concentrate instead on ground static tests of motors. ARS founder G. Edward Pendray gave this object to the Smithsonian in 1966.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.