Onboard Radar Display for VFR Collision Avoidance

Abstract

In VFR (visual flight rules) situations the pilot is responsible for collision avoidance. This can be problematic in case of high-speed business jets entering the vicinity of a local airport. Often, this airspace is occupied by slow, low-visibility aircraft like gliders, ultralight vehicles or, occasionally, balloons. These may be not equipped with active transponders. Thus, it is up to the pilot of the jet to take care of see-and-avoid separation. Onboard collision avoidance radar with appropriate display systems can assist at this task. We investigated the use of a newly developed radar-system that can display proximity traffic. Sources of detection may by active radar, ADS-B and TCAS. These sources are properly fused to avoid double-targets. Optionally, an avoidance trajectory can be proposed to the pilot. In a pilot-study a simulation of the system was set up and tested in varying conflict situations. Pilots were asked to evaluate their impressions of safety in each situation. We discuss if the use of active radar is a promising option for increasing situational awareness and flight safety.