Engineering topics
Publications and source records attributed to Harvey H Hubbard.
Principal noise problems for propeller and jet powered V/STOL aircraft, large high altitude supersonic aircraft, and special mission aircraft for supersonic flight at low altitudes
Some aspects of the helicopter noise problem are briefly discussed. These discussions deal with the nature of the problem, some tentative criteria for use in evaluating it, and the physical characteristics of noise from helicopters. Overall noise data are presented for a reciprocating-engine helicopter along with discussions of the characteristics of noise from its various components such as the engine, gearing, and rotors. Some consideration is also given to the noise from tip jet rotor systems