The missile's propulsion system consisted of a XLR35-RM-1 composed of four thrust chambers, built by Reaction Motors, which produced of thrust each and could independently swivel up to ten degrees on one axis. The gimbaling motion was used to control the flight path of the missile, replacing the system of the V-2 missile that used moving fins placed within a fixed engine. The gimbal system adds complexity to the engine mounting but preserves more of the energy of the rocket exhaust during maneuvering. The engine had a specific impulse of sea level.