Noise Reduction for Business Jet Aircraft.
Abstract
An analysis is made of the noise reduction potential for the business jet aircraft fleet registered in the United States as of 1975. Noise characteristics of each aircraft are defined at various thrust levels and noise reductions achievable for different design options are determined. Costs and performance penalties are assessed for each option in order to evaluate the consequences of lowering present FAR 36 Appendix C noise levels. With current technology, the exhaust noise of all engines can be reduced significantly with multi-element nozzles, but the addition of a lined ejector provides little additional noise reduction at greatly increased weight and performance penalties. Acoustic liners in exhaust ducts reduce fan or core noise for some engines but inlet liners have little value. Equipping aircraft with new engines achieves major noise reductions but is technically and economically reasonable for only about twenty percent of existing business jet aircraft. To assess noise reductions, a single number criterion is proposed, based on the effective perceived noise level contour that circumscribes a two square-mile area. Also it is recommended that takeoff noise be measured at 2.5 nautical miles from brake release.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1976
- Accession Number
- ADA031149
Entities
People
- Colin G. Gordon
- John F. Mills
- John F. Wilby
- William J. Galloway
Organizations
- BBN Technologies