Abstract: Apparatus for reducing ground erosion caused by impinging hot jets such as the lifting jets of VSTOL aircraft or rockets, said jets emanating from a hot jet nozzle such as a lift engine nozzle or a lift/propulsion engine nozzle, comprising means for introducing a coolant fluid to an impingement surface immediately beneath the turning zone.

Abstract: A variable cycle gas turbine bypass engine includes a first fan 1 located at an inlet to the engine so as to provide air to a compressor 2 driven by a turbine 11 and to a bypass duct 13 surrounding the compressor housing. A second fan 5 located in the bypass duct 13 is driven by a free turbine 12. A controllable area auxiliary air intake 4 and bypass duct blocker doors 3 are located between the first and second fans 1, 5. Control means are effective for selectably operating the bypass duct blocker doors 3 and the auxiliary air intake 4 to vary in operation the bypass ratio of the engine. Thus in conventional wing-borne flight, the intake 4 is closed and the bypass duct 13 is unobstructed, and the combined exhausts from the bypass duct 13 and the turbines 10, 11 and 12 pass to a tailpipe 14, which has a vectorable nozzle 8, to produce forward thrust.

Abstract: A gas turbine powerplant simulator arrangement includes an engine body 2, an intake 13 and exhaust nozzles 3, 4. An air intake flow duct 12 extends from the air intake 13. There is a first primary injector 7, 7a adjacent the intake 13 and includes a primary drive gas inlet 15 connectible to a gas supply source. The flow duct 12 includes an excess flow discharge duct 27 and a balance flow passageway 19a communicating a second primary injector 9 located intermediate the air intake 13 and the adjacent exhaust nozzle 3. The second injector 9 includes its own primary drive gas inlet 28 connectible to an independent gas supply source. The injectors 7, 7a and 9 extend across the full flow cross-section of the duct 12.