Smith System Engineering says that it has reduced the number of false alarms produced by its low-cost aircraft-proximity warning system for light aircraft, after completing an initial 50h of flight testing.
The system is being designed and tested by Smith under contract to the UK Civil Aviation Authority Safety Regulation Group, and it is aimed at reducing the risk of light aircraft being involved in mid-air collisions in the future.
It uses 12 solar cells fitted to the wings and tail of the aircraft, and a cockpit processing and display unit. Other aircraft can be detected at ranges of up to 1km (0.5nm) when their strobe lights, which are illuminated for around 0.5milliseconds for each flash, are picked up by the solar cells, even during bright daylight.
According to Martin Robson, Smith's project leader, a high level of false alarms was generated when flight testing began, because development was based on lighting conditions on the ground.
"We found that lighting conditions when airborne are quite a bit different," says Robson. "We have been tweaking the system to match average lighting conditions-we have had problems with false alarms, but have managed to combat this."
Robson believes that it is now operating effectively, recording a false-alarm rate of around 10%. "On an average flight, a pilot will encounter around ten other aircraft and, provided that there is only one false alarm per flight, the system will be believable to the pilot," says Robson.
Tests are under way on a Piper Cadet aircraft operated by Oxford Air Training School in the UK. The project is scheduled to be completed later this year, when Smith submits its report to the CAA for evaluation.
Source: Flight International
