Accession Number:

AD0260759

Title:

GROUND AND IN-FLIGHT ACOUSTIC AND PERFORMANCE CHARACTERISTICS OF JET-AIRCRAFT EXHAUST NOISE SUPPRESSORS

Descriptive Note:

Corporate Author:

NATIONAL AERONAUTICS AND SPACE ADMINISTRATION WASHINGTON D C

Report Date:

1961-08-01

Pagination or Media Count:

1.0

Abstract:

Characteristics were determined for a twin-engine jet aircraft with the following configurations 1 eight-lobe exhaust noise suppressors, 2 eight-lobe nozzles and ejectors, and 3 the unmodified aircraft. In-flight sound pressure levels measured on the ground under the flight path were reduced 5 to 6 decibels by the suppressors. Similar reductions in perceived noise level occurred. Increases in total drag coefficient of 3 and 7 percent and decreases in specific range of 5 to 14 percent were found to result from the suppressor configurations. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE