Measurement of Rocket Engine Spark Gap Ignition EMC

A spark may be used to ignite nonhypergolic rocket engine propellants. Broad-band radiated interference from the spark plug will be radiated through the thrust chamber throat and will limit the level to which interference can be reduced. Tests have been performed by Textron's Bell Aerospace Company to determine the extent to which the rocket engine thrust chamber attenuates radiated interference from the spark. Results indicate that, for small reaction control type engines, compliance with typical EMC specifications is a reasonable possibility.