SIDE-BY-SIDE HOVER PERFORMANCE COMPARISON OF MDHC 500 NOTAR™ AND TAIL ROTOR ANTI-TORQUE SYSTEMS

A flight test of a 530N “first generation-production” prototype NOTAR helicopter and a 530FF tail rotor equipped helicopter was performed to study and compare the hover performance of the two helicopters. The purpose of this test program was to accurately compare the anti-torque and total system performances of both helicopters. Results from the flight test show the two helicopters require the same power to hover in-ground-effect at 36 inch skid height, and to hover-out-of-ground-effect. The NOTAR-equipped 530N used less main rotor power per pound of gross weight as compared to the 530FF, However, the 530N required a higher percentage of anti-torque power versus total power than the 530FF. Improvements have been identified that can improve the efficiency of the next generation of NOTAR systems which would reduce the total hover power required to below that of tail rotor equipped helicopters.