Evaluation of Unites States Air Force Portable Airfield Lighting System

An evaluation of a prototype portable airfield lighting system was conducted for the United States Air Force by the Federal Aviation Administration at the National Aviation Facilities Experimental Center (NAFEC), Atlantic City, New Jersey. The system was designed to provide both day and night visual guidance in VFR and IFR weather straight-in and circling approaches and landings.

The system was installed in the approach zone to Runway 4 along with an alternate approach light system designed to a minimum configuration based on previous tests at NAFEC on simple approach light systems. Comparative tests were conducted using Precision Approach Radar (PAR) in weather conditions of approximately 1/2-mile visibility. Motion picture film was taken of the segment ahead of the aircraft and the PAR scope was photographed three times a second to obtain data on approach light system effectiveness. A post-flight questionnaire also was used to obtain pilot reaction to the effectiveness of the visual guidance received. Data were obtained on circling and straight-in approach guidance in VFR weather conditions. Integrity and reliability data were obtained by USAF personnel stationed at NAFEC but were not included In the report by the Federal Aviation Administration.

The very limited weather data obtained in the six-week test period indicated that both systems would provide minimum acceptable visual guidance in 3/4-mile visibility conditions with the alternate approach light system preferred in 1/2-mile visibility conditions primarily due to the additional length of 900 feet (2400 feet versus 1500 feet). The runway edge lighting used in the portable approach light system provided adequate straight-in guidance, but circling guidance was inadequate for both day and night conditions. Several recommendations were made concerning the design of the brightness control, interlocking of systems through the cons ole, and the method of supporting the approach and runway edge lighting fixtures.