One of Dubai's famed Jetmen killed in a crash in November failed to deploy the emergency parachute attached to the winged engines strapped to his back, an investigation found.
Investigators from the General Civil Aviation Authority gave no explanation why Vincent Reffet, 36, of Annecy, France, did not use his parachute in the fall during a training flight in the desert.
Describing Mr Reffet as an "experienced professional skydiver" and jetwing pilot, the investigators said a video from the November 17 crash appeared to show him lose control and go into a backflip, hovering about 240 metres above the ground.
Such backflips are common when wearing the wings and recoverable if the pilot thrusts forward through the flip, the report said.
Mr Reffet had experience coming out of those flips, but at higher altitudes, Associated Press reported, citing the findings.
"The risks of the 800-feet hover were discussed during the pre-flight briefing and, as a risk mitigation, it was decided to abort the flight and to deploy the pyro-rocket emergency parachute should the jetwing become uncontrollable," the report said.
“The investigation could not determine why the pilot did not choose this mitigation action.”
Video from a camera attached to Mr Reffet's helmet showed the parachute deployed only after he crashed to the ground. Prior to that, his hands moved as though he thought he could enter into a hover again, the report said. The jetwing showed no mechanical problems before or during the flight, investigators said.
The training flight was to simulate a take-off from the ground, a triangular flight and a jet-powered landing on a 244-metre platform, the report said. A helicopter at that altitude was to simulate the platform, but investigators found no sign it played a part in the crash.
Flight sponsors XDubai did not comment on the report, nor did Jetman Dubai, for whom Mr Reffet flew.
“The loss of Vince Reffet was devastating to his family, many friends, and colleagues," said a Jetman Dubai Spokesperson.
"Immediately following the accident, our top priority was to support both his family and colleagues, as well as provide our full assistance to the UAE General Civil Aviation Authority (GCAA) as they conducted their investigation into the circumstances of the accident.
"Our thoughts remain with Vince’s family and friends.”
Mr Reffet previously base-jumped off the Burj Khalifa, the world's tallest building, setting a world record. He earned gold medals while competing as a free-flying skydiver and competed as an extreme athlete.
Pilots for Jetman Dubai, founded by Swiss adventurer Yves Rossy, zip across the sky with a four-engine, carbon-Kevlar wing strapped to their backs. The wings can fly 50 kilometres, have a maximum speed of more than 400kph and can reach an altitude of 6,100 metres.
In 2015, Mr Reffet and Mr Rossy flew alongside an Emirates Airbus A380 double-decker jetliner over Dubai.
