A PLANE crash in which two amateur pilots miraculously survived was probably caused by insufficient airspeed, according to an Air Accident Investigation Branch report.

The reason behind the lack of speed, which meant the plane may not have reached sufficient height after take-off, has not been identified, but modifications to the aircraft type have been made since the accident last year.

The crash, involving an Avid MK4 Speedwing, happened at Full Sutton Airfield, Pocklington at about 1pm on May 11 when the weather was fine with little cloud.

Pilot and owner Tim Allen, 47, and his passenger Paul Freeman, 53, both of Harewood, between Harrogate and Leeds, were both left with serious injuries.

According to the report, Mr Allen said the aircraft took off quite normally, but when it was between 125 and 150 feet above the airfield it failed to respond to either stick or rudder input.

He recalled warning his passenger that they had a serious problem, but remembered nothing more until he regained consciousness days later.

The aircraft crashed nose-down into the ground about 50 metres beyond the end of the strip, still within the airfield boundary.

Both occupants suffered multiple serious injuries. Mr Allen was in hospital for about 25 days and Mr Freeman was hospitalised for nine days.

The report said: "The most likely cause of the accident was insufficient airspeed and this deduction is consistent with the passenger's impression of low speed....Moreover, in the opinion of the AAIB the loss of control had to have occurred at a very low height for the occupants to have survived the crash.

It said that at "an average speed of 68 mph the aircraft should have been airborne for not less than ten seconds. In that time it should have gained at least 95 feet in height, but the damage to the aircraft suggests that it did not do so."

The low height could have been caused if the engine was not producing full power or the aircraft was mishandled.

Design deficiencies in the Speedwing's flight control systems have since been identified and simple modifications have been developed.

Updated: 11:07 Friday, March 08, 2002