Meteorological and Ground Effects on the Propagation of Aircraft Noise Close to the Earth's Surface
Abstract
Dickinson (J. Sound and Vib 47, 438-443, 1976) reported observations of unexpectedly low attenuations between aircraft take-off noise levels measured at ranges of 320 m and 2900 m at London (Gatwick) Airport. The anomalous attenuation were attributed to the effects of focussing by a temperature inversion. These data are investigated and a ray trace study shows that the low attenuations are unlikely to be caused by atmospheric focussing by the temperature inversion. Further, it is shown that a combination of the effects of a finite impedance ground and of atmospheric refraction is overcoming part of the ground absorption at the distant position can adequately explain the observed data.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1977
- Accession Number
- ADA054968
Entities
People
- C. I. Chessell