Abstract: In liquid propellant rocket engines, spark igniters are often used indirectly to light preburners, gas generators, and main chambers [1]. Attraction for spark igniters is strongly influenced by their ability for repeatable engine starts and high reliability. In the case of spark igniters, however, ignition is reliant upon an ignitable mixture passing near the spark tip very early in the engine start transient, prior to pressure quenching of the spark. While direct ignition of rocket engine co…