AAIB investigation to Brian Taylor AT6, (UAS registration n/a)

A large model aircraft was being flown at a club site when communication between the pilot and with the aircraft was lost. The aircraft struck the side of a parked lorry trailer in a distribution park. The cause of the communication loss could not be determined.

History of the flight

The Brian Taylor AT6 is a 1:5 scale flying model of the North American T-6 Texan (Harvard). It has a wingspan of 2.3 m (92”), a takeoff mass of 5.4 kg (12 lb) and is powered by a 29.35 cc (1.79 cu in) four-stroke engine using a fuel mixture of methanol, nitromethane and oil.

The aircraft was flown at a model flying club airfield near a distribution centre and the pilot had completed multiple circuits of the field when he lost communication with the UA. The unresponsive aircraft maintained a straight and level attitude in a north-easterly direction, at approximately half throttle, until it struck the side of a parked curtain-sided lorry trailer.

A witness nearby heard the impact and reported that the engine continued to run after the aircraft had been destroyed.

The function of the aircraft systems had been checked by the pilot prior to take off, the battery was charged and its voltage verified. Examination by the pilot and other club members after the accident, could not identify any faults which would explain the loss of communication.

It was suspected by the pilot that 2.4 GHz jamming devices were being operated by some of the companies at the distribution centre to prevent staff from using mobile telephones.

It was confirmed to the AAIB that no such devices were in operation. Furthermore it is an offence under section 68 of the Wireless Telegraphy Act 20061 to “use any apparatus, including jammers, for the purposes of deliberately interfering with wireless telegraphy (radio communications) in the UK”

AAIB
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