What happened
On 6 February 2025, a Boresight BQ400 Raider LR was being operated for commercial purposes at Throckmorton Airfield in Worcestershire. The flight was part of a development program to test a ground-based product, following a planned path along a disused runway. The flight team consisted of a pilot and two observers.
Upon arming the aircraft, the quadcopter took off and ascended to an altitude of approximately 20 metres. Shortly after takeoff, the aircraft veered westward. The pilot attempted to use the controller to correct the flight path, but the BQ400 Raider LR failed to respond to any manual inputs. To prevent further uncontrolled flight, the pilot used a disarm function via a laptop-based control system to terminate the flight. The aircraft traveled roughly 320 m from the launch point before crashing into the ground. The impact occurred approximately 4 m from an uninvolved person, who sustained no injuries. The aircraft was destroyed upon impact.
The investigation
The investigation examined the aircraft, the flight conditions, and the operational setup. The aircraft was a new unit, marking its first flight for this specific airframe. To assist with altitude monitoring during the test, the operator had attached a 3-metre rope with a small metal weight to the aircraft. While this method was unconventional, it had been used successfully in previous flights without issue.
Investigators confirmed that the pilot held a valid CAA Flyer ID and that the flight was conducted within the A3 Open Category, maintaining the required horizontal distance from populated areas. The weather at the time was clear with a temperature of 1°C and a light northerly breeze.
Findings
- The aircraft experienced uncontrollable flight behavior immediately following takeoff.
- The pilot was unable to regain command of the aircraft using the handheld controller.
- The aircraft was a new unit, and the specific technical failure within the system was not identified.
- The use of a rope and weight as a manual altitude indicator was not considered a contributing factor to the crash.