HELICOPTER BLADE SLAP,

Abstract

The paper considers a possible mechanism for the generation of blade slap. A simplified theory for this is presented which shows good agreement with the results obtained from a test rig on which blade slap was simulated. In particular it show that the noise is dependent on the fourth power of the velocity and the square of the gust size (vortex strength). The results are sufficiently encouraging to warrant the extension of the analysis to that of an actual helicopter. Normally, blade element velocity in a helicopter can not be varied appreciably; it is fixed by far more important aerodynamic considerations. The profile of a vortex and its path are very important considerations that may possibly be partially controllable. Because the noise increases with the square of the vortex velocity amplitude (W), highly loaded rotor blades, which produce a strong tip vortex have a greater penchant toward loud blade slap. This contributes to the severity of the blade slap on the IROQUOIS which has a highly loaded two-bladed rotor. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1966
Accession Number
AD0634644

Entities

People

  • F. Webb Taylor
  • John W. Leverton

Organizations

  • University of Southampton

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Agreements
  • Aircrafts
  • Airframes
  • Amplitude
  • Demographic Cohorts
  • Helicopter Rotors
  • Helicopters
  • Rotary Wing Aircraft
  • United States Military Academy
  • Vehicles

Fields of Study

  • Physics

Readers

  • Aerodynamics/Aeronautics.
  • Aerospace Engineering
  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.