Optimal Helicopter Operation Considering Power Failure Possibilities

This paper summarizes our previous work (Refs. 1-4) on optimal control of helicopters following power failure, with emphasis on its application to the analysis of operating limitations to assure safety in case of power failure. The height-velocity boundary, required takeoff field length, and maximum takeoff weight determined theoretically and experimentally correlate reasonably well, hence the presented theory can be used to reduce the cost, time, and risk involved in flight tests for certification. In addition, it can be used to determine optimal takeoff procedures of helicopters and tiltrotors for transport category operations such that the takeoff weight is maximized according to the available field length.