Further Sensitivity Studies of Community-Aircraft Noise Exposure (NOISEMAP) Prediction Procedures.
Abstract
This report describes the results of studies of the sensitivity of the noise exposure contours to various model parameters and assumptions presently in the NOISEMAP procedure. The areas within Day/Night Level (LDN) contours for ten Air Force airbases increased by 11 to 4O percent when the noise measure was adjusted for the presence of pure tones. The contour areas for typical mixed fighter, bomber/tanker, and training airbases were reduced by 3 to 11 percent by substitution of the SAE algorithms for ground-to-ground propagation and transition models, whereas adding the fuselage shielding algorithm reduced the contour areas by 13 to 22 percent. Since there is little firm evidence showing one set of algorithm more accurate than the other, the present NIOISEMAP models will be retained until further technical analyses or new data show a clear basis for alteration. The contour areas for typical National Guard and combined bomber/tanker/fighter airbases for standard day weather conditions were reduced by up to 10 percent using sumner-type climate conditions, but were reduced by 18 to 60 percent by winter weather conditions. Although use of standard dry conditions results in contours that are quite representative for most bases, it is recommended that contours be developed based on a simple review of the absorption coefficients (for the 1000 Hz one-third octave frequency band) determined from the set of monthly average temperatures and relative humidities.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1977
- Accession Number
- ADA301331
Entities
People
- Dwight E. Bishop
- John F. Mills
- Richard D. Horonjeff
- Thomas C. Dunderdale
Organizations
- BBN Technologies