Impact of Prediction Accuracy on Costs - Noise Technology Applications in Helicopters

Abstract

This study is an extension of the work reported in AD-A083 935, and considers the effect which uncertainties in the prediction and measurement of helicopter noise have on the development and operating costs. Although the number of helicopters studied is too small to permit generally applicable conclusions, the following are the primary results: (1) the Effective Perceived Noise (EPN) Levels tended to be overpredicted for takeoffs, underpredicted for approaches, with no general trend noted for level flyovers; (2) prediction accuracy for the cases studied ranged from 1 to 6 EPNdB; and (3) test and measurement repeatability can give a range of up to 3 EPNdB. Each helicopter must be studied as an individual case and generalization of cost trends should be avoided.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1981
Accession Number
ADA101768

Entities

People

  • H. Sternfeld Jr.
  • R. H. Spencer

Organizations

  • Boeing Rotorcraft Systems

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Accuracy
  • Acoustics
  • Aircraft Equipment
  • Aircrafts
  • Airframes
  • Data Acquisition
  • Data Analysis
  • Flight
  • Frequency
  • Helicopter Rotors
  • Helicopters
  • Mach Number
  • Measurement
  • Noise
  • Noise Reduction
  • Sound Pressure
  • Tail Rotors

Readers

  • Acoustics.
  • Calculus or Mathematical Analysis
  • Computational Modeling and Simulation