Results 251 to 260 of about 64,082 (287)

A Comparative Study of Tail Rotor Noise Mechanisms

Journal of the American Helicopter Society, 1986
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. Both harmonic and broadband noise were analyzed. The disturbed flow into the tail rotor was modeled using combinations of aerodynamic and acoustic flow codes along with some necessary ...
A. R. George, S. ‐T. Chou
openaire   +1 more source

Prediction of Main Rotor, Tail Rotor and Engine Parameters from Flight Tests

49th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference <br> 16th AIAA/ASME/AHS Adaptive Structures Conference<br> 10t, 2008
In the framework of this research project, the main rotor torque, tail rotor torque, engine torque and main rotor speed of a helicopter in forward flight are estimated by using a state space model from flight tests data. The state space model inputs are nonlinear terms made of combinations of pilot controls and helicopter states.
Michel Nadeau Beaulieu, Ruxandra Botez
openaire   +1 more source

Method for the Extraction of Helicopter Main and Tail Rotor Noise

Journal of Aircraft, 2018
In this paper a method for the extraction of main and tail rotor noise from an acoustic pressure time history of a helicopter is described.
openaire   +2 more sources

Cracking in a Tail Rotor Blade in a Helicopter

2005
Abstract The tail rotor blade of a helicopter developed a visible crack during service. The cracked region was removed from the blade and the fracture surface was examined in a SEM, revealing shallow pitting on the inside surface of the skin and a corresponding reduction in thickness. Based on these findings, investigators concluded that
openaire   +1 more source

Aeroacoustic investigation of a ducted tail rotor

AIAA AVIATION 2023 Forum, 2023
Prateek Jaiswal, Jose Rendon, Yann Pasco, Marlène Sanjosé, Stephane Moreau   +4 more
openaire   +1 more source

Tail Rotor Performance in Presence of Main Rotor, Ground, and Winds

Journal of the American Helicopter Society, 1974
Wayne Wiesner, Gary Kohler
openaire   +1 more source

Numerical investigation and optimization for interior duct shape of ducted tail rotor

Aerospace Science and Technology, 2021
Chenkai Cao, Guoqing Zhao, Qijun Zhao
exaly  

Solid Lubricants for Helicopter Tail Rotor Gearboxes

1970
Abstract : Solid lubricants as retainers in rolling bearings and as idlers for load gearswere evaluated in a Bell UH-1 helicopter tail rotor drive gearbox under normallubricated conditions and also under emergency conditions of dry operation.Solid lubricants provided satisfactory gearbox operation using conventionalfluid lubrication in all tests at ...
openaire   +1 more source

Description of a Dynamical Framework to Analyse the Helicopter Tail Rotor

Dynamics, 2021
Salvador Castillo-Rivera, M Tomás-Rodríguez   +1 more
exaly  

Composite Bearingless Tail Rotor for UTTAS

Journal of the American Helicopter Society, 1977
Ronald R. Fenaughty, William L. Noehren
openaire   +1 more source