A former Royal Air Force pilot lost control of his light aircraft in Dubai due to powerful turbulence caused by a commercial jet, an investigation has concluded.
Briton David Phillips, 52, was among four people who died when the low-wing Diamond DA62 aircraft they were travelling in smashed into a nature reserve on May 16 last year.
Aviation experts investigating the cause of the tragedy released their final report on Sunday.
It concluded that a Thai Airways Airbus A350-900 on approach to a parallel runway created a large wake vortex that destabilised the smaller aircraft.
“The cause of the accident was a loss of control induced by an encounter with wake vortices generated by the preceding A350,” the report said.
“It was identified that the approaches during this mission were flown with spacings less than the separation minimums provided by air traffic control to flights operating under instrument flight rules.
“It was also identified that the wake turbulence advice provided by Air Traffic Control during the first five approaches did not prompt the flight crew to increase the distance to preceding aircraft on approach to the parallel runway.”
The crash occurred at about 7.30pm as the light aircraft prepared to approach Dubai International Airport.
The pilot and his first officer were completing a series of flights to calibrate safety lighting on runways.
Having taken off from Sharjah International Airport, the five-seater aircraft was on its 10th approach when it crashed.
Shortly after levelling off for its final turn about 400 metres above ground, the DA62 rolled to the left and dropped about 30 metres in altitude.
Phillips was able to briefly regain control of the plane before it lurched to the left again, this time sending the aircraft into a nosedive.
Others on board the flight included first officer William Blackburn, 26, British citizen Christopher Stone, 59, and South African Fritz Venter.
The pilot and first officer had flown together on 28 occasions since 2018 and had a combined airtime of more than 4,000 hours.
The role of Stone, a flight inspector, was to conduct the in-flight calibration assessment of airport lighting from the passenger seat.
Wreckage of the aircraft, owned by UK company Flight Calibration Services, indicated it clipped a tree shortly before hitting the ground close to Mushrif Park.
Its seats were found 50 to 68 metres away from the main crash site and a trail of burnt debris extended up to 160 metres.
After their investigation, experts made a series of recommendations to avoid similar tragedies.
The Air Accident Investigation Sector recommended the plane’s operator conduct a comprehensive review of safety management systems and pilot training with particular attention on pilot decision-making.
The report also recommended commercially operated light aircraft should be equipped with cockpit image and audio recording systems, similar to a black box, to help monitor flights.
The findings were issued to the UAE's General Civil Aviation Authority to ensure air navigation service providers reviewed working processes for air-traffic controllers.
Guidelines also suggested Dubai airports worked to mitigate factors relating to wake turbulence from large aircraft that affects smaller planes.