Accession Number:

ADA526482

Title:

Jet Engine Noise Reduction

Descriptive Note:

Corporate Author:

NAVAL RESEARCH ADVISORY COMMITTEE ARLINGTON VA

Personal Author(s):

Report Date:

2009-04-01

Pagination or Media Count:

100.0

Abstract:

This study was initiated to investigate the jet engine noise problem that U.S. Navy and Marine Corps personnel experience on carriers and amphibious assault ships and propose actions to reduce noise in existing and next generation tactical jet aircraft engines. An overarching finding of this study is the paucity of engineering quality data. Standardized engine noise data to compare the engine noise among different aircraft or among various engines do not exist, and the available data do not correlate Sailor or Marine hearing loss with their respective noise exposure environments. Also, standards do not exist for acquiring engine noise data for tactical aircraft. Although the U.S. Department of Veterans Affairs VA is spending over 1 billion per year for hearing loss cases, there are no data to correlate hearing loss claims to flight deck noise exposure. Approximately 28 of the VA hearing loss claims are for the Department of the Navy, but data do not exist on the environment that caused the hearing loss. Flight deck noise is a serious health risk. The noise levels on Navy flight decks - up to 150 dB - exceed the ability of currently available hearing protection to attenuate the noise to safe levels for the time that our personnel are exposed to high noise. On a positive note, significant progress is being made in the development of improved hearing protection equipment, such as the deep insert ear plugs which are undergoing an operational assessment onboard USS Dwight D. Eisenhower CVN-69. Although the noise levels of commercial jet airliners have been decreasing, the noise levels of tactical jet aircraft have not. In all likelihood, tactical jet noise levels have increased as the velocity and airflow from these engines have increased to produce added thrust. There are exceptions, such as the RA-5C which made its last deployment in 1979, which is reported to have had the highest noise level of any Navy tactical jet aircraft.

Subject Categories:

  • Aircraft
  • Acoustics
  • Jet and Gas Turbine Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE