Results 81 to 90 of about 15,084 (235)
Performance Data from a Wind-Tunnel Test of Two Main-rotor Blade Designs for a Utility-Class Helicopter [PDF]
An investigation was conducted in the NASA Langley Transonic Dynamics Tunnel to evaluate an advanced main rotor designed for use on a utility class helicopter, specifically the U.S. Army UH-60A Blackhawk.
Singleton, Jeffrey D. +2 more
core +1 more source
Calculated Hovering Helicopter Flight Dynamics with a Circulation Controlled Rotor [PDF]
The influence of the rotor blowing coefficient on the calculated roots of the longitudinal and lateral motion was examined for a range of values of the rotor lift and the blade flap frequency.
Chopra, I., Johnson, W.
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Helicopter low-speed yaw control [PDF]
, 1993 A system for improving yaw control at low speeds consists of one strake placed on the upper portion of the fuselage facing the retreating rotor blade and another strake placed on the lower portion of the fuselage facing the advancing rotor blade.
Crowell, Cynthia A. +2 more
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Jixie chuandong, 2017 The torsional vibration dynamics analytical model of rotor power transmission system is built,the shimmy collectivity mode of vibration and frequency of rotor blade are obtained,it is indicated that the propulsion/transmission system will influence ...
Lai Lingyun, Zhang Ruochen, Liu Yongzhi
doaj
Structural optimization of composite helicopter rotor blades
, 2020 Structural optimization of a helicopter rotor blade with uniform aerodynamic surface and twist at the functional region is performed for weight minimization subject to various constraints relevant to helicopter rotor blades. The genetic algorithm based optimization is performed only for the functional region of the blade.
openaire +2 more sources
Performance of an optimized rotor blade at off-design flight conditions [PDF]
An investigation is made of the dynamic and aerodynamic performance of a helicopter rotor previously optimized for minimum 4/rev vertical shear and blade weight subject to certain dynamic and structural constraints.
Chattopadhyay, Aditi
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Mars Science Helicopter Conceptual Design [PDF]
, 2020 Robotic planetary aerial vehicles increase the range of terrain that can be examined, compared to traditional landers and rovers, and have more near-surface capability than orbiters. Aerial mobility is a promising possibility for planetary exploration as
Balaram, Jayarao +15 more
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Model helicopter rotor high-speed impulsive noise: Measured acoustics and blade pressures [PDF]
A 1/17-scale research model of the AH-1 series helicopter main rotor was tested. Model-rotor acoustic and simultaneous blade pressure data were recorded at high speeds where full-scale helicopter high-speed impulsive noise levels are known to be dominant.
Boxwell, D. A. +3 more
core +1 more source
Examining the stability derivatives of a compound helicopter [PDF]
, 2016 Some helicopter manufacturers are exploring the compound helicopter design as it could potentially satisfy the new emerging requirements placed on the next generation of rotorcraft.
Ferguson, Kevin, Thomson, Douglas
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A flight investigation of blade section aerodynamics for a helicopter main rotor having NLR-1T airfoil sections [PDF]
A flight investigation was conducted using a teetering-rotor AH-1G helicopter to obtain data on the aerodynamic behavior of main-rotor blades with the NLR-1T blade section.
Morris, C. E. K., Jr. +2 more
core +1 more source