What happened
A training flight was being conducted by a training captain and a line captain as part of a routine base check. The flight began with a departure from London Airport at 0755LT, followed by a landing at Blackbushe after the initial portion of the check was completed.
At roughly 0850LT, the crew initiated a second takeoff from Blackbushe for further exercises. As the aircraft reached its takeoff safety speed, the training captain performed a simulation of an outer starboard engine failure. During this maneuver, just as the aircraft departed the ground, the inner starboard propeller stopped rotating. The aircraft subsequently entered a right-hand turn with increasing bank angle.
After reaching an altitude of approximately 30 feet, the aircraft descended and struck the ground 250 yards from the runway in a nose-down, steeply banked position. The impact caused the aircraft to cartwheel and slide backward for 200 yards before coming to a stop near the northwest boundary of the aerodrome. The incident resulted in major impact damage and a fire that nearly destroyed the airframe. All five occupants managed to escape the wreckage with only slight injuries.
Findings
The investigation determined that the accident was caused by an operational error during the engine failure simulation. While attempting to simulate a failure of the number 4 engine, the training captain mistakenly operated the number 3 high pressure cock lever. This mistake led to a total loss of power from both starboard engines at the most critical moment of the takeoff sequence.