Results 191 to 200 of about 15,230 (231)

Crack Propagation in Helicopter Rotor Blades

1971
Design criteria are presented for the residual strength and life of fatigue loaded helicopter structures. The crack propagation rate methods and data are reviewed, and a bilinear semilog method is shown to be most accurate for predicting residual life. The methods developed are compared with full scale rotor blade fatigue data.
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Mechanical Stability of a Two-Bladed Cantilever Helicopter Rotor

Journal of the Aeronautical Sciences, 1956
SUMMARY A theoretical analysis of the mechanical stability of a twobladed cantilever helicopter rotor, whose hub is mounted upon isotropic elastic supports in the horizontal plane and whose elastic blades employ fixed root attachments, has been made and is reported here.
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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
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Active rotor control for helicopters: individual blade control and swashplateless rotor designs

CEAS Aeronautical Journal, 2011
Modern helicopters still suffer from many problems that hinder a further increase in their efficiency, acceptance and hence their market share. The high level of vibrations and the noise generated by the rotor are the most important reasons for this. Vibrations are problematic not only for pilot and passenger comfort, but also give rise to an increase ...
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Stability of a Flexible Helicopter Rotor Blade in Forward Flight

Journal of the Aeronautical Sciences, 1956
The problem of the stability of the transient motion in the flapping plane of a flexible helicopter rotor blade in forward flight is considered. The formulation of the problem considers two degrees of freedom—rigid flapping and elastic bending. A new method of determining the transient stability of the motion is developed, using the concept of ...
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Design and Production of Fiberglass Helicopter Rotor Blades

1980
The design of a helicopter rotor blade requires close attention to aerodynamic, dynamic, structural and mechanical considerations, and manufacturing methodology.
C. E. Covington, P. S. Baumgardner
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Unsteady Air Loads on Helicopter Rotor Blades

The Journal of the Royal Aeronautical Society, 1964
An appropriate introduction to the topic of this lecture is the following comment taken from Cierva's third and last lecture presented before this Society in 1935:“Perhaps the most irritating of the secondary difficulties met with in the Autogiro development have been those of a dynamical nature.
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The Heavy Lift Helicopter Rotor Blade

Journal of the American Helicopter Society, 1974
T. Scarpati, R. Sandford, R. Powell
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Multi-objective sensor placement optimization of helicopter rotor blade based on Feature Selection

Mechanical Systems and Signal Processing, 2022
João Luiz Junho Pereira, Matheus Brendon Francisco, Sebastiao Simöes Cunha   +2 more
exaly  

High-fidelity simulation of blade vortex interaction of helicopter rotor based upon TENO scheme

Chinese Journal of Aeronautics, 2023
Wei Bian, Guoqing Zhao, Qijun Zhao
exaly