Using Enhanced Flight-Vision Systems (EFVS) for low-visibility taxi in transport category aircraft

Two studies (using Boeing 777 and 737 simulators) examined flight crews’ use of an Enhanced Flight Vision System (EFVS) for low-visibility taxi operations. Twenty-five flight crews completed 21 short taxi scenarios under combinations of the following: Runway visual range (RVR: 300, 500, and 1000 ft); EFVS on head-up display (on/off); Airport infrastructure - 3 levels. The use of EFVS produced fewer route deviations, most at 300 feet RVR with edge lights and standard centerline or routes with LVO/SMGCS “enhancements” (without centerline lights). Larger turn angles and lower visibilities were associated with slower rates of travel. Crews detected the obstacle on the right-side most of the time and twice that of the left-side obstacle. Regardless of EFVS, crews had more route deviations on larger (>90 degrees) turns and right turns, possibly from loss of visual references in the turn. Recommendations are provided regarding benefits and limitations of EFVS for low-visibility taxi with suggestions for additional research