TheChitterneFlyer:
"When 'Reverse' was selected....the aeroplane departed the runway".
A particularly clever trick indeed since the Argosy wasn't equipped with reversing propellers!
The fatal at Boscombe Down was XR105 on 27.04.76. An Italian Air Force officer, who was attending the Empire Test Pilots School course, lost control on a 2-engined approach. He and the flight engineer were killed.