FAA Office of Aerospace Medicine
Civil Aerospace Medical Institute

Report No: DOT/FAA/AM-18/16

Title and Subtitle: UAS Pilot Traffic Avoidance Maneuver Preferences, Response Times, and ATC Interaction Decisions

Report Date: September 2018

Authors: Williams K, Caddigan E, Zingale C

Abstract: This report is a follow-on analysis of maneuver data, pilot response time data, and air traffic control interaction data that was collected in a research study by Williams, Caddigan, and Zingale (2017). That study was conducted to assist the standards development group, RTCA Special Committee 228, in the establishment of minimum information requirements for Unmanned Aircraft System (UAS) Detect and Avoid (DAA) traffic displays. The research tested four different display configurations. These were a baseline display, and the baseline display with either a closest point of approach (CPA) indication, avoidance area information, or banding information that provided horizontal and vertical vectors to avoid to prevent a loss of well clear from an intruder aircraft. Details of that research are provided in Williams et al. (2017).

The follow-on analysis of maneuver data showed that pilots were influenced by the type of display they were using. Both the baseline and CPA displays biased pilots more toward vertical avoidance maneuvers while the avoidance area and banding displays biased pilots toward horizontal avoidance maneuvers. In addition to display type, avoidance maneuvers were influenced by encounter geometry. Pilots were biased toward vertical maneuvers if ownship was descending at the time of the encounter. They were biased toward horizontal maneuvers if the intruder was climbing or descending. Finally, there was some evidence to suggest that pilots were biased toward vertical maneuvers when time to closest point of approach to the intruder was less than 60 seconds.

The maneuver response time data lend additional support to the use of suggestive maneuver information as part of the minimum information requirements for DAA traffic displays. Again, as was the case with well clear violation data reported in Williams et al. (2017), support was found for both the banding and avoidance area displays when it was shown that pilot maneuver responses were significantly faster using those displays than when using the baseline display. Ramifications of these results for DAA display design are discussed.

Key Words: Detect and Avoid, Unmanned Aircaft Systems, UAV, Unmanned Aircraft, Control Station, Traffic Display, TCAS

No. of Pages: 25