In deflagration to detonation supersonic igniter the fuel and oxidizer is ignited with a conventional spark plug. The flame thus developed is made to travel through a Shchelkin spiral placed inside the tube.

The spiral acted as a blockage and the subsonic flame gets converted to detonation wave. A introduction of secondary source of fuel in the detonating tube results in an effective enhancement of ignition in detonation engines.

The supersonic igniter can be used to initiate supersonic /detonating wave in high enthalpy engines like Pulse Detonation Engines (PDE), Continuous Rotating Detonation Engines (CRDE).