An aircraft crash that claimed four lives, including that of a Bradford businessman, has sparked a warning from accident investigators.

Experienced flyer Gerry Davitt - who ran a Wakefield Road lorry tarpaulin firm - was killed alongside his father Laurence and two other men when their private aircraft came down in a North Yorkshire field last year.

A report into the tragedy by the Air Investigation Branch showed the 1981 Mooney M20J G-BIWP plane suffered a loss of power before it plummeted to the ground. Investigators said the autopilot may have masked warning signs that it was falling until too late.

Gary Davitt, 42, of Naburn, North Yorkshire, and his father Laurence, 67, of Heworth, died instantly when the single engined plane plunged into a field at Hemingbrough and burst into flames. Also killed were Paul Blackburn, of Spofforth, and Kenneth Moore, 51, of Harrogate.

The four seater had just taken off from Sherburn-in-Elmet and was heading for Holland when it appeared to go stall.

The report said that, as the craft went into a downwards spin from 2,400 feet, cloud cover would have limited the pilot's vision and may have disorientated him.

It added: "There was insufficient height available to recover below the cloud."

The document concluded that without appropriate training, a pilot may become misled by autopilot facility. It recommended that all private flyers should receive "adequate" training in their use.

It added: "In this case it appears the autopilot contributed to disguising the loss of power and impending stall from the pilots."

According to the investigators, the pilots were not in "good flying practice" because they had not flown much in the six weeks before the crash. The power loss may have been associated with fuel supply. It is unclear who was piloting the plane.

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