Hypergolic Ignitor Assembly

An ignitor for use with the MC-I rocket engine has a cartridge bounded by two end caps with rupture disc assemblies connected thereto. A piston assembly within the cartridge moves from one end of the cartridge during the ignition process. The inlet of the ignitor communicates with a supply taken from the discharge of the fuel pump. When the pump is initially started, the pressure differential bursts the first rupture disc to begin the movement of the piston assembly toward the discharge end. The pressurization of the cartridge causes the second rupture to rupture and hypergolic fluid contained within the cartridge is discharged out the outlet. Once the piston assembly reaches the discharge end of the cartridge, purge grooves allow for fuel and remaining hypergolic fluid, to be discharged out the ignitor outlet into the combustion chamber to purge the ignitor of any remaining hypergolic fluid.