Gust-Tunnel Investigation of the Effect of a Sharp-Edge Gust on the Flapwise Blade Bending Moments of a Model Helicopter Rotor
Abstract
Preliminary investigations have been made in the Langley gust tunnel to determine the effects of a sharp-edge vertical gust on the blade flapwise vibratory bending moments of small model rotors having either fixed-at-root or teetering blades. Both rotor configurations were tested up to a tip-speed ratio of about 0.35. The results for simulated forward flight indicate that the effect of the gust on the maximum vibratory bending moment is of less importance for the teetering rotor than for the fixed-at-root rotor. Increasing the rotor speed decreases the magnitude of the vibratory bending moments resulting from a given gust. At a given rotor speed, the magnitude of the vibratory components due to the gust increases with increasing tip-speed ratio. Increasing the rotor speed at a constant forward velocity decreases the maximum vibratory bending moments for all conditions tested. The rate of increase of the vibratory bending moments with tip-speed ratio is approximately twice as great for the fixed-at-root rotor as for the teetering rotor.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1955
- Accession Number
- ADA377151
Entities
People
- Domenic J. Maglieri
- Thomas D. Reisert
Organizations
- National Aeronautics and Space Administration