Ignition was initiated by an automotive-type spark plug located about behind the shutter system, electricity to the plug being supplied from a portable starting unit. Three air nozzles in the front of the pulse jet were connected to an external high pressure air source which was used to start the engine. Acetylene was used for starting, and very often a panel of wood or similar was held across the end of the tailpipe to prevent the fuel from diffusing and escaping before ignition was complete.