Rocket Engine, Liquid Fuel, Nike-Ajax

This liquid propellant rocket engine of the Nike-Ajax, built by the Aerojet General Corporatoin, is the U.S.'s first operational surface-to-air missile. The missile used a solid propellant booster and liquid propellant second stage. The liquid sustainer engine produced 2,600 pounds of thrust for about 20 seconds. It used red fuming nitric acid and JP-4, a type of jet fuel, as its propellants. It was a very simple system with no moving parts for ease in operation and high reliability.

The propellants were forced into the combustion chamber by compressed air. Development of the engine was begun in late 1945 by Aerojet-General and the missile became operational in 1953 and remained in service until 1963. This object was donated to the Smithsonian in 1968 by the Aerojet General Corp.