Abstract: A fuel leakage protection system is disclosed for a gas turbine engine having a fuel system that has a plurality of fuel nozzles that are spaced around a combustor section, a plurality of fuel tubes that are connected to the fuel nozzles individually, two generally semi-circular fuel manifolds that are located aft of the fuel nozzles and that ar connected to the fuel tubes and a branch manifold that is connected to the fuel manifolds.The fuel leakage protection system comprises a collar assembly encapsulating each fuel supply fitting connecting a fuel tube to a fuel nozzle or the branch manifold to a fuel manifold to trap leakage fuel. A fuel collection manifold collects leakage fuel from the collar assemblies via a plurality of fuel return tubes that are connected to the manifold at one end and fluidly connected to the collar assemblies at the other end.

Abstract: A rocketjet engine has a light, hollow double-acting compressor piston (35 and 123). It is reciprocated by a smaller-diameter double-acting power piston (51) through a power shaft (52 and 60) connecting them. Up to 90 percent of intake air is routed from a compressor cylinder (36) to a thruster (1 and 106) and the remaining ten percent to a power cylinder (55). Fuel and water are preheated and sprayed into the power cylinder with phase-change injectors 67-70 at ends of compression strokes after complete flame-front propagation to actuate the compressor with combined combustion and steam pressure. To provide steam-propulsion pressure in addition to peak-heat combustion pressure and to cool the thruster, fuel is preheated and spray injected into an upstream combustor (8 and 109) portion of the thruster (1 and 106).