Visual factors affecting pilots' judgments of the distance to the touchdown point during emergency landings

The purpose of this research was to determine whether identifiable visual factors contribute to misperceptions which may occur when a pilot judges the distance to a selected touchdown point during an emergency landing. The importance of two particular visual experiences, which most pilots do not encounter during routine flight operations, was evaluated: (1) the view of the world seen from the unusually steep bank angle in which the pilot may place the airplane while maneuvering at a low altitude, and (2) the added visual distraction of a “windmilling” propeller. The influence of environmental structure was also considered. Studies of these factors were conducted using a visually realistic cockpit mounted within a VisionDome® virtual-reality environment. Behavioral responses were collected from both naive participants and experienced pilots under conditions which represented emergencies initiated at a variety of altitudes and positions with respect to the landing field. The findings indicated that judgments of the distance to the touchdown point made while the airplane is banked and turning are underestimated, whereas judgments made while the airplane is on an unbanked and straight approach to the touchdown point are overestimated. Additionally, pilot experience was associated with improved judgment accuracy during the banked flights, but decreased accuracy on the unbanked flights. In most cases, the windmilling propeller decreased touchdown point judgment accuracy. Consistent visual misperceptions do occur during simulated emergency landings. Incorporating exposure to these misperceptions into the required flight-training curriculum may decrease the accident rate associated with off-airport emergency landings.