Accession Number:

AD0702422

Title:

NOISE ENCOUNTERED IN ROTARY-WING AIRCRAFT

Descriptive Note:

Final rept. Feb 1962-Apr 1969

Corporate Author:

SCHOOL OF AEROSPACE MEDICINE BROOKS AFB TX

Personal Author(s):

Report Date:

1969-12-01

Pagination or Media Count:

34.0

Abstract:

The acoustic environment within rotary-wing aircraft consists of a mixture of noises. The report identifies, describes, and illustrates the primary and secondary noise-producing mechanisms associated with helicopter operation. The noise sources include main rotors, antitorque rotors, main and secondary transmission and gear-shaft distribution systems, and auxiliary power units. In addition to describing specific noise generators, the report presents composite noise envelopes illustrating typical noise environs of rotary-wing vehicles having different configurations of rotor - to - power plant matings. Alterations in internal noise which occur during conditions of hover and forward flight are described and aeromedical factors such as speech interference and potential auditory risk are identified.

Subject Categories:

  • Helicopters
  • Stress Physiology
  • Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE