Performance ofthe Runway-Status Light System at Logan Airport

.. Runway incursions are a persistent problem in airport ground-movement operations. Numerous critical conflicts and several fatal accidents have occurred as a result of unauthorized or otherwise inappropriate entry of aircra& or surface vehicles onto an active runway. Many of these conflicts developed quickly, leaving little time for effective intervention by either the controller or the pilots involved. A reliable system of automatic runway-status lights would be an 'effective way to prevent such time-critical incursions. The runway-status light '·'system (RSLS) at Boston's Logan International Airport is an off-line proof-of'concept technology-demonstration system designed to show that automatically operated runway-status lights can promptly and reliably transmit runway-status information to pilots and surface-vehicle operators, thereby preventing unsafe runway entry or unsafe takeoff. •' ,The demonstration system does not include actual lights on the airport ,s~ce but has relied instead on an illuminated airport model board, which has allowed system development to proceed in a realistic operating environment of live airport traffic without interfering with airport operations. The results of an "'initial proof-of-concept assessment indicate that the system performs well, even though it is an early prototype. Missed-detection and false-alarm rates are low; " and interference with normal airport operations promises to be negligible. The d,emonstration has shown the techriical feasibility of a system of automatic ,runway-status lights. A'' S AIR TRAFFIC CONTINUES to increase, traffic ", loads at major airports are expected to grow , proportionally, placing an increasingly heavy burden on the tower controllers who must expedite the movement of this traffic safely and efficiently. Dangerous and occasionally fatal runway conflicts have occurred in the past. Many of these conflicts developed quickly, leaving little time for effective intervention by either the controller or the pilots involved. Some of these conflicts are described in this issue in the article by Harald Wilhelmsen entitled "Preventing Runway Conflicts: The Role of Airport Surveillance, Tower-Cab Alerts, and Runway-Status Lights." Although surface safety at most of the world's major airports is exemplary, the important task ofmaintaining and improving safety in the face of increased surface congestion requires continuing effort. A system of automatic runway-status lights has been proposed as a means of preventing time-critical runway conflicts by indicating runway status to pilots and surface-vehicle operators [1]. These lights would tell pilots when conditions are unsafe for takeoff, and tell both pilots and surface-vehicle operators when a runway is unsafe to enter. Such a warning system, operating continuously, automatically, and promptly without human intervention, represents a last line of