OH-6A Phase II Quiet Helicopter Program

Abstract

The report presents the results of the Phase 2 Quiet Helicopter Program. A Hughes OH-6A Light Observation Helicopter was extensively modified to obtain a maximum of quieting. The purpose was to apply the latest known sound-suppression techniques available to industry to an actual helicopter and then to measure the results. An acoustic goal was set which required a balanced treatment of each noise-producing source throughout the full frequency range. Noise reductions ranged from 14 to 20 db depending on the flight conditions. The report describes the detailed configuration changes, the test and development programs, and the final sound level measurements compared to the standard OH-6A.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1972
Accession Number
AD0753646

Entities

People

  • Harold W. Ferris
  • William C. Mccluskey
  • William H. Barlow

Tags

Communities of Interest

  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Acoustic Measurement
  • Acoustics
  • Aerodynamic Configurations
  • Aircrafts
  • Airfoils
  • Airframes
  • Contracts
  • Drive Shafts
  • Engine Noise
  • Exhaust Systems
  • Governments
  • Materials
  • Measurement
  • Recording Systems
  • Resonant Frequency
  • Sound Pressure
  • Tail Rotors

Fields of Study

  • Physics

Readers

  • Acoustics.
  • Software Engineering