A New Method for Measuring the Transmissivity of Aircraft Transparencies
Abstract
Transmissivity is a measurement of the relative amount of light transmitted through a part. It is an important optical parameter for aircraft transparencies, since it determines the apparent brightness of the objects observed outside the cockpit. Because visual parameters such as acuity, contrast threshold, and color perception vary with brightness at low luminance values, transmissivity can have a direct effect on vision. The transmissivity of aircraft transparencies is currently measured following the American Standard for Testing and Materials Test Method D-1003. This method, originally intended for the measurement of small, thin, flat parts, has several shortcomings for measuring aircraft transparencies. A new method for measuring transmissivity, which overcomes the shortcomings of D-1003, is described. The precision of both methods was determined in laboratory tests; the results of these tests are presented. The new test method, in addition to its application advantages, is slightly more precise than ASTM D-1003. Keywords: Windscreens, Windshields, Canopy.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1989
- Accession Number
- ADA216953
Entities
People
- Harold S. Merkel
- Harry L. Task
Organizations
- Armstrong Laboratory