This SAE Aerospace Information Report (AIR) provides definitions of and inspection criteria for defects commonly encountered in molded and finished glass covers for exterior aircraft lighting. This document covers, but is not limited to, visual inspection and evaluation recommendations for molded glass covers used in exterior aircraft lighting applications. The included definitions are for those defects most commonly encountered. The goal is to provide specific evaluation criteria in the following areas: a. color; b. internal quality; c. external (surface) quality; d. dimension; and e. coatings.
Inspection of glass covers shall be made at a typical reading distance with normal or corrected 20-20 vision under adequate lighting. Covers shall be free from defects which will prevent meeting intensity and beam distribution, strength, thermal shock, and other physical requirements. All covers shall be manufactured and finished using quality workmanship.
The AIR has been revised to further clarify glass quality definitions and add dimesions to glass defects that are commonly present in glass lenses.