Interlaboratory Study (ILS) on the Standard Test Method for Measuring Grid Line Slope (GLS) in Aerospace Transparencies

When an observer looks through an aerospace transparency, relative optical distortion may result, specifically in thick, highly angled, multi- layered plastic parts. Distortion occurs in all transparencies but is especially critical to aerospace applications such as combat and commercial aircraft windscreens, canopies and cabin windows. This is especially true during certain operations such as takeoff, landing and aerial refueling. It is critical to be able to quantify optical distortion for procurement activities. The test method covers apparatus and procedures that are suitable for measuring the grid line slope (GLS) of transparent parts including those that are small or large, thin or thick, flat or curved, or already installed. This ILS determined the test method's measurement precision.Air Force Research Lab Wright-Patterson AFB OH Human Effectiveness Directorate is the author of 'Interlaboratory Study (ILS) on the Standard Test Method for Measuring Grid Line Slope (GLS) in Aerospace Transparencies' with ISBN 9781423550754 and ISBN 1423550757.