Accession Number : ADA133408

Title :   Study of Noise-Certification Standards for Aircraft Engines. Volume 2. Procedures for Measuring Far Field Sound Pressure Levels around an Outdoor Jet-Engine Test Stand.

Descriptive Note : Final rept.,


Personal Author(s) : Marsh,Alan H

Full Text :

Report Date : Jun 1983

Pagination or Media Count : 88

Abstract : This study, reported in three volumes, had the purpose of considering the feasibility of establishing an FAA requirement for a manufacturer of aircraft engines to demonstrate compliance with an engine noise-level standard in order to obtain an engine-noise type certificate. The objective of engine-noise type certification would be to supplement the aircraft-noise type certification requirements in Part 36 of the Federal Aviation Regulations. The scope of the study was limited to aircraft turbofan engines. Volume 2 describes the general characterisitics of 16 outdoor engine test stands used by 11 organizations for measurements of engine noise levels. Instruments and microphone installations are also described. Recommendations are presented for test procedures to measure farfield sound pressure levels around a turbofan engine mounted on an outdoor test stand. After adjusting the measured data to common reference conditions, the test results should be suitable for demonstrating compliance with the requirements for a static-engine noise type certificate.

Descriptors :   *Turbofan engines , *Aircraft engine noise , *Noise reduction , Test stands , Noise , Level(Quantity) , Sound pressure , Methodology , Installation , Microphones , Data acquisition , Surveys , Configuration management , Field tests , Measurement

Subject Categories : Acoustics
      Jet and Gas Turbine Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE