Abstract: An improved prechamber and fuel manifold structure for a gas turbine engine having a premixing-prevaporizing type combustor, the improvement residing in the provision of a prechamber having an internal cylindrical surface swept by swirling pressurized air passing through the prechamber from a plenum to the combustor and in the provision of a fuel manifold having a plurality of individual fuel conduits extending from a remote fuel supply pipe to a corresponding plurality of delivery heads in the prechamber. The delivery heads direct fuel generally tangent to the internal cylindrical surface to form a film for vaporization in the passing air and the length of the fuel conduits and the flow areas of the fuel conduits and the delivery heads are generally equal so that fuel flow in the fuel conduits is balanced and so that when the conduits are opened to atmospheric pressure at termination of combustion, purging of residual fuel to foreclose coking is rapid and complete.