HC Deb 21 November 1977 vol 939 cc568-70W
Sir David Renton

asked the Secretary of State for Defence whether he will now make a full statement on the cause of the crash of the RAF Canberra on the Oxmoor Estate, Huntingdon, on 3rd May, which caused loss of life.

Mr. Wellbeloved

This aircraft had been engaged on a routine training exercise to be followed, on return to its base at Wyton, by a practice overshoot on asymmetric power. This particular manoeuvre involves approaching the runway with one of the two engines throttled back, but still running, and is designed to simulate the handling and safe recovery to base of the Canberra aircraft after failure of one engine. The manoeuvre itself is not in any way dangerous but, as with many aircraft manoeuvres, it requires the proper technique to be used. The pilot had been instructed in this technique and was in practice.

On this occasion, the pilot started the manoeuvre normally. He approached the runway at Wyton with a right-hand turn from a height of about 1,000 feet, descending to about 600 feet and with the right-hand engine throttled back. It was expected that at the point where the aircraft would have ended its turn into line with the runway, its wings would have been levelled. This did not happen, but instead the aircraft's angle of bank to the right increased, leading rapidly into a downward spiral. It crashed nearly vertically into the ground in the Oxmoor estate.

The investigation revealed no evidence of pre-impact damage or technical malfunction in the aircraft; nor from the evidence could any cause be established with absolute certainty. But it was concluded that the most probable cause was that the crash resulted from the pilot's misjudgment in starting his overshoot without first levelling the wings. This, combined with too much power on the left engine, led to a loss of directional control; there was insufficient height available in which to recover.

On behalf of the Royal Air Force I offer my deepest sympathy to all who have suffered loss in this tragic accident.

I have already explained on 8th November 1977, to the right hon. and learned Member the measures being taken with regard to the basic flying patterns at Wyton and the air traffic procedures at Wyton and Alconbury.—[Vol. 938, c. 972-4.] In addition, we are carrying out a comprehensive review of the asymmetric techniques for the Canberra PR-9 aircraft and in the mean time some handling limitations have been applied to this type of flying with this aircraft.