Once near the launch ramp, the wing spar and wings were attached and the missile was slid off the loading trolley, Zubringerwagen, onto the launch ramp. The ramp catapult was powered by the Dampferzeuger trolley. The pulse-jet engine was started by the Anlassgerät, which provided compressed air for the engine intake,and electrical connection to the engine spark plug, and autopilot. The Bosch spark plug was only needed to start the engine, while residual flame ignited further mixtures of gasoline and air, and the engine would be at full power after 7 seconds. The catapult would then accelerate the bomb above its stall speed of 200 mph, and ensuring sufficient ram air.