Optical Radiation Transmittance of Aircraft Windscreens and Pilot Vision
Abstract
Optical radiation can have acute and chronic effects on the tissues of the eye, especially if exposure levels exceed normal repair capabilities. In support of a Department of Homeland Security project, the transmittance properties of aircraft windscreens were measured at the FAA's Civil Aerospace Medical Institute (CAMI) for both visible and invisible optical radiation. This paper focuses on windscreen transmittance in the ultraviolet (UV) (< 380 nm) and visible (380-780 nm) portions of the optical spectrum. Transmission measurements were performed on eight aircraft windscreens. Three windscreens were from large commercial jets (MD 88, Airbus A320, and Boeing 727/737); two from commercial, propeller-driven passenger planes (Fokker 27 and the ATR 42); one from a small private jet (Raytheon Aircraft Corporation Hawker Horizon); and two from small general aviation (GA), single-engine, propeller-driven planes (Beech Bonanza and Cessna 182). The two GA aircraft windscreens were plastic (polycarbonate); the others were multilayer (laminated) composite glass. UV transmittance for both glass and plastic windscreens was less than 1% for UV-B (280-320 nm) radiation. In the UV-A portion (320-380 nm) of the spectrum, transmittance differences increased from 0.41% to 53.5%, with plastic attenuating more UV radiation than glass. For visible light, average transmittance from 400-600 nm (violet to orange) was similar (82.8% 4.6%) for both windscreen materials, while from 625 to 775 nm (orange to red), the difference in average transmittance increased from 9.1% to 40.0%, respectively, with plastic transmitting longer wavelengths more efficiently.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2007
- Accession Number
- ADA471609
Entities
People
- Ron W. Montgomery
- Van B. Nakagawara
- Wesley J. Marshall
Organizations
- Federal Aviation Administration