Abstract: A twin spool counter-rotating turbofan gas turbine engine having a counter-rotating fan module integrated with the high pressure compressor and driven by a counter-rotating turbine utilizing only two drive shafts. The two drive shafts are aerodynamically coupled and rotate in opposite directions relative to each other with or without the use of a gearbox. The integration between the fan module and high pressure compressor allows the fan blade rows to operate at the same mechanical speed of the high pressure compressor blade rows. An afterburner module may be added to the present invention to provide thrust augmentation.

Abstract: Active recovery from a rotating stall operating condition in an axial flow compression system is accomplished by altering the temperature and/or density of the working fluid flowing in the inlet of the compression system once rotating stall is detected. A burner is used to increase the compressor inlet flow temperature and concomitantly reduce the inlet flow density. Alternatively, a low density gas such as helium is injected into the compressor inlet. The ingestion of high temperature gases or other low density gases into the compressor energizes a dynamic response from the compression system that induces rotating stall recovery.

Abstract: A twin spool counter-rotating turbofan gas turbine engine having a counter-rotating fan module integrated with the high pressure compressor and driven by a counter-rotating turbine utilizing only two drive shafts. The two drive shafts are aerodynamically coupled and rotate in opposite directions relative to each other with or without the use of a gearbox. The integration between the fan module and high pressure compressor allows the fan blade rows to operate at the same mechanical speed of the high pressure compressor blade rows. An afterburner module may be added to the present invention to provide thrust augmentation.