Low-Speed Wind-Tunnel Test of an Unpowered High-Speed Stoppable Rotor Concept in Fixed-Wing Mode

Low-Speed Wind-Tunnel Test of an Unpowered High-Speed Stoppable Rotor Concept in Fixed-Wing Mode
Author: National Aeronautics and Space Adm Nasa
Publisher: Independently Published
Total Pages: 56
Release: 2018-10-29
Genre:
ISBN: 9781729371077

An experimental investigation of the M85, a High Speed Rotor Concept, was conducted at the NASA Langley 14 x 22 foot Subsonic Tunnel, assisted by NASA-Ames. An unpowered 1/5 scale model of the XH-59A helicopter fuselage with a large circular hub fairing, two rotor blades, and a shaft fairing was used as a baseline configuration. The M85 is a rotor wing hybrid aircraft design, and the model was tested with the rotor blade in the fixed wing mode. Assessments were made of the aerodynamic characteristics of various model rotor configurations. Variation in configurations were produced by changing the rotor blade sweep angle and the blade chord length. The most favorable M85 configuration tested included wide chord blades at 0 deg sweep, and it attained a system lift to drag ratio of 8.4. Lance, Michael B. and Sung, Daniel Y. and Stroub, Robert H. Ames Research Center; Langley Research Center...

Aeronautical Engineering

Aeronautical Engineering
Author:
Publisher:
Total Pages: 580
Release: 1971
Genre: Aeronautics
ISBN:

A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA)

Wind-Tunnel Investigation of a Quarter-Scale Two-Bladed High-Performance Rotor in a Freon Atmosphere

Wind-Tunnel Investigation of a Quarter-Scale Two-Bladed High-Performance Rotor in a Freon Atmosphere
Author: Charles D. Lee
Publisher:
Total Pages: 168
Release: 1971
Genre:
ISBN:

A joint USAAVLABS/NASA-Langley/Bell Helicopter Company experimental investigation of a quarter-scale two-bladed teetering rotor system was conducted in the NASA-Langley Transonic Dynamics Tunnel using Freon as a test medium. Rotors tested were a dynamically similar Bell 540 rotor having -10-degree twist, and a thin-tipped rotor having 0-degree twist. Aerodynamic and loads data were obtained at advance ratios from 0.30 to 0.72 in combination with advancing-tip Mach numbers varying from 0.70 to 0.96. These data were compared to full-scale data and theory. In general, the aerodynamic test data followed predicted trends and correlated well with full-scale tunnel data in the areas of low blade loading at low advance ratio and low advancing-tip Mach numbers. The blade loads data followed the expected trends, but their magnitudes could not be readily compared to existing flight test data due to the differences between the flight test conditions, model test conditions attained, and hub impedance differences. (Author).