by Sibley School of Mechanical and Aerospace Engineering, Cornell University, National Aeronautics and Space Administration, National Technical Information Service, distributor in Ithaca, New York, [Washington, DC, Springfield, Va .
Written in English
|Statement||Albert R. George and S.-T. Chou|
|Series||NASA contractor report -- NASA CR-176829|
|Contributions||Chou, S. T, United States. National Aeronautics and Space Administration|
|The Physical Object|
A study was made of helicopter tail rotor noise, particularly that due to interactions with the main rotor tip vortices, and with the fuselage separation mean wake. The tail rotor blade-main rotor tip vortex interaction is modelled as an airfoil of infinite span cutting through a moving : A. R. George, S. T. Chou. A study was made of helicopter tail rotor noise, particularly that due to interactions with the wakes of the main rotor, hub, and fuselage, and with the engine exhaust. Thereafter the method is applied to wind tunnel data and flight test data for two different helicopters, one with a traditional tail rotor (Bo) and one with a modern Fenestron (EC). The results illustrate that a traditional tail rotor displays a rather tonal noise signature very similar to that of the main rotor, only smaller in amplitude and on a shorter time : W. F. J. Olsman. 1 ANALYSIS OF TAIL ROTOR NOISE REDUCTION BENEFITS USING HELINOVI AEROACOUSTIC MAIN/TAIL ROTOR TEST AND POST-TEST PREDICTION RESULTS J. Yin, A. Dummel1, D. Falchero2, M. Pidd3, J. Prospathopoulos4.
This is a collection of the Ray Prouty's columns in Rotor and Wing and American Helicopter Society's Vertiflite magazine from to Preview this book» What people are saying - Write a review. The Defender is single rotor and uses what is called the Coanda Effect instead of a tail rotor to counteract torque. Air is bled from the engine through a rotatable slot in the tail boom. CoNV 2D, a conventional helicopter with a single main rotor system and tail rotor. This is a dual structure design using the same airframe, hub and landing gear as the CoAX 2D, but substituting other conventional components such as a tail rotor, drive system and the standard main rotor head. There will also be provision for a twin-engine version. Tail rotor for an MHR Sea Hawk. A helicopter main rotor or rotor system is the combination of several rotary wings (rotor blades) and a control system that generates the aerodynamic lift force that supports the weight of the helicopter, and the thrust that counteracts aerodynamic drag in forward flight.
A Comparative Study of Tail Rotor Noise Mechanisms Journal of the American Helicopter Society, Vol. 31, No. 4 Two-dimensional blade-vortex flow visualization investigation. Get this from a library! Helicopter tail rotor noise analyses: final technical report period, June 1, - Janu [Albert R George; S T Chou; United States. . A study is made of helicopter tail rotor noise, particularly that due to the interactions with main rotor tip vortices. Summarized here are present analysis, the computer codes, and the results of several test cases. Amiet's unsteady thin airfoil theory is used to . The calculations follow closely the standard methods of aerofoil theory but the rotor analysis is simplified. In tail rotor pitch-flap instability, the flapping and lagging motions are coupled. Since the original publication of 'Bramwell's Helicopter Dynamics' in , this book has become the definitive text on helicopter dynamics and.