Flight crew use of a traffic display to supplement visual separation during night visual approaches

At many busy airports maximum efficiency and minimum delay occur when visual approaches are being conducted by pilots using visual separation from traffic. Pilot willingness to accept responsibility for visual separation during visual approaches affords controllers maximum flexibility. It may be possible to continue visual approaches during conditions when they are currently suspended if pilots are able to perform similar tasks by reference to a cockpit display of traffic information (CDTI) in lieu of visual contact out-the-window. This concept has been developed under the name CDTI enhanced flight rules (CEFR); however, this paper will use the more descriptive term of CDTI assisted visual separation (CAVS). This study is the fourth and final in a series designed to examine the feasibility of CAVS. Previous laboratory simulations have indicated pilot acceptance of the concept and the CDTI feature set. In this simulation, CAVS was examined in the context of night visual approaches using a full two person crew. Seventeen commercial airline pilots flew a series of simulated visual approaches, while maintaining a self-determined separation from the traffic to follow (TTF). The CDTI was located in the throttle quadrant forward console area, which represented a near-term implementation. Speed management was used to adjust spacing to a pilot-determined value. Independent variables included the availability of range ring with alerting (on or off) and the occurrence of a selected target degrade event. This paper will present the results from the range alerting variable, which was included to examine aids to flight crew spacing judgment. The objective and subjective results indicate that pilots are willing and able to perform the CAVS procedure during night conditions and in two-flight-crew-member operations. The range ring cue and associated range alerts received mixed results as to their use in performing the procedure.