IMPROVED STATIC AND DYNAMIC PERFORMANCE OF HELICOPTER POWERPLANT

The paper covers features Inherent in the helicopter as an aircraft, and operating conditions of its powerplant, the influence of the latter on the static and dynamic performance of engines and the helicopter as a whole in accordance with the laws limiting the maximum engine parameters. Reasons for the integrated control of the helicopter and the powerplant are given with due account of specific features of this type of aircraft. Consideration of the existing problems in this aspect has allowed us to do the following; to optimize the takeoff power limitation in accordance with the engine parameters; to develop recommendations leading to Improved helicopter takeoff and hovering safety as well as improved powerplant static and dynamic performance and stabilized engine parameters in flight in turbulent air. Data obtained from spectrum analysis of the thermal effect produced by reingestion of the exhaust gases into the compressor inlet are presented. They are applicable to single rotor helicopters powered by turbine engines (with takeoff weight over 9,000 kg). Data obtained from investigations of the turbine engine takeoff power augmentation by injecting water into the compressor inlet and limiting simultaneously the maximum gas temperature at this power rating are given. This method of augmenting the engine takeoff power when the helicopter is operated at high ambient temperatures and at high altitudes is promising as it allows to maintain the aircraft flight productivity with a minimum increase in the design weight.