Frangibility Tests of Existing Approach Lamps and Holders

Tests were conducted on approach lamps and holders to determine to what extent current designs are frangible. A catapult accelerated the fuselages of two widely used types of small aircraft to collision with PAR-38 and PAR-56 lamps and associated holders. A total of 53 runs at different speeds and with different exposed lamp face orientations resulted in evidence that most small, general aviation aircraft windshields will shatter with lamp penetration at less than flying speeds. Results show that a safety redesign of the lamps might reduce penetration probability and result in a lamp that will not penetrate windshields at less than approach landing speeds.