Abstract:
A power train having a gas turbine engine with a controlled power transfer clutch between the compressor turbine and the load turbine driving a power shift transmission. The engine control system includes a fuel control and a power and torque program control responsive to compressor and auxiliary torque and speed controlling the power transfer clutch to provide engine output power and maintain constant high turbine inlet temperature in a wide range of operation for optimum efficiency. The power shift transmission control has shift control valving to selectively supply control pressure to the fluid operated drive motors to selectively establish neutral and a plurality of drives. A flow valve responsive to flow filling a motor for establishing a drive controls a power transfer clutch cut off valve to disconnect the power transfer clutch providing normal engine idle during establishment of a drive. Energizing the starter circuit requires first manually placing the transmission control in neutral and then discontinues fluid feed to the engine and transmission controls, unloads the engine and transmission pumps, disengages the power transfer clutch, provides a low idle throttle stop and further ensures positive neutral in the transmission. When the engine is started and the transmission control is in neutral, the engine power clutch is disengaged, the throttle stop is in low idle, the transmission is in positive neutral and only lubrication pressure is supplied to the transmission.