Identification and Proposed Control of Helicopter Transmission Noise at the Source
Abstract
Helicopter cabin interiors require noise treatment which is expensive and adds weight. The gears inside the main power transmission are major sources of cabin noise. This paper describes work conducted by the NASA Lewis Research Center in measuring cabin interior noise and in relating the noise spectrum to the gear vibration of the Army's OH-58 helicopter. Flight test data indicate that the planetary gear train is a major source of cabin noise and that other low frequency sources are present that could dominate the cabin noise. Companion vibration measurements were made in a transmission test stand, revealing that the single largest contributor to the transmission vibration was the spiral bevel gear mesh. Our current understanding of the nature and causes of gear and transmission noise is discussed. The authors believe that the kinematical errors of the gear mesh have a strong influence on the noise. This paper summarizes completed NASA/Army sponsored research that applies to transmission noise reduction. The continuing research program is also reviewed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 19, 1987
- Accession Number
- ADA219535
Entities
People
- David G. Lewicki
- Eugene A. Krejsa
- John J. Coy
- Robert F. Handschuh
- Ronald G. Huff
Organizations
- United States Army Aviation and Missile Command