Defence

A Raytheon Cobra unmanned air vehicle crashed at the US Air Force Academy in Colorado Springs, Colorado on 28 July as school administrators evaluated the platform for use in its advanced airmanship course for cadets.

According to a preliminary report by the US National Transportation Safety Board, the UAV struck a stadium-style light pole as it neared its pre-programmed landing location on a road next to athletic fields north of the campus at the end of the presentation.

The vehicle received "substantial" damage to the right wing, which separated from the aircraft and became stuck in the lights, as well as to the nose, landing gear and tail boom.

Raytheon was operating the UAV, which has a 3.1m (10.3ft) wingspan and maximum take-off weight greater than 45kg (100lb), under a letter of authorisation from the US Federal Aviation Administration. The Cobra was the third UAV to receive an FAA experimental airworthiness certificate and the first of its size to gain certification, says Raytheon.

According to the NTSB, the Raytheon team had surveyed the athletic fields before the flight and had programmed the GPS waypoints for a rectangular course using the Cobra's ground control station. After a normal autopilot take-off and route, the single-engined UAV was returning to the road for landing when it undershot the turn from base leg to final.

Operators commanded the aircraft to make another approach, upon which the Cobra overshot the turn from base leg to final. Rather than take over manual control, the operators elected to let the Cobra automatically correct its path, but in the process, it struck the light pole.

Raytheon was unavailable to comment.