The Feasibility and Use of Anti-Torque Surfaces Immersed in Helicopter Rotor Downwash

摘要

An analytical investigation was made of the effectiveness of anti-torque aerodynamic surfaces immersed in helicopter rotor downwash. It is shown that additional vertical tail surface having areas equal to about two percent of the main rotor disk area could provide torque trim for speeds above about 75 ft/sec for representative current vehicles. (Author)