A Study of the Effect of Terrain on Helicopter Noise Propagation by Acoustical Modeling

Abstract

An experimental program was conducted to evaluate the applicability of acoustical modeling techniques to study the effects of terrain on helicopter noise propagation. Comparison of model results with flyover data of a full scale UH-1 helicopter showed very good correlation with 500 ft altitude data and moderately good correlation with 50 ft altitude data. Model studies of the effects of the blocking and channeling of sound by barriers, such as hills, shows good correlation with expected results for simple cases with the model providing useful results for more complex cases. Further full scale verification is recommended to further exchange confidence in the modeling technique for application to helicopter detection studies.

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Document Details

Document Type
Technical Report
Publication Date
Mar 23, 1981
Accession Number
ADA097626

Entities

People

  • Harry Sternfeld Jr.

Organizations

  • Boeing Rotorcraft Systems

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms

DTIC Thesaurus Topics

  • Absorption
  • Absorption Coefficients
  • Accuracy
  • Acoustics
  • Aircrafts
  • Attenuation
  • Electromagnetic Radiation
  • Flight Paths
  • Generators
  • Helicopters
  • Line Of Sight
  • Losses
  • Measurement
  • Reflection
  • Scattering
  • Simulations
  • Verification

Fields of Study

  • Physics

Readers

  • Acoustics.
  • Aviation Science / Aeronautics.
  • Computational Modeling and Simulation