Test Approach Lighting for Displaced Thresholds

The purpose of this project was to determine the extent to which multiple semiflush-mounted in-runway lighting fixtures, both steady-burning and condenser-discharge types, could replace above-ground approach lighting fixtures to obtain an interim displaced threshold approach lighting system. The tests compared the characteristics of readily available touchdown zone fixtures in multiple groupings with those of single above-ground fixtures.

The project involved flight tests under actual weather conditions, analysis of the physical and mechanical properties of the individual components, and photometric measurements of the lighting configurations and components.

The results of the tests indicated that the steady-burning fixtures were adequate for Category I operations and marginally adequate for Category II operations. The multiple condenser-discharge fixtures were adequate for Category I operations and marginally adequate for the higher RVR limits (approximately 1,800 feet and above) of Category II operations.

RD-66-66
Author: E.L. Reamer