With 7 parachutists on board, the engines of a Beechcraft 65-A90 King Air were started and the pilot taxied the aircraft to the runway at Pitt Meadows Airport (British Columbia, Canada). With a take-off weight of approximately 7500 pounds, its weight was well within the certified Maximum Take-Off Weight of 9650 pounds. The take-off was uneventful.
The accident site, looking in direction of travel and the initial touchdown point(© TSB) During the climb out on a westerly heading at a speed of 110 knots while at ~3900 feet above sea level, the aircraft shuddered and yawed to the right. The aircraft was levelled off and the righthand engine (a Pratt & Whitney CanadaPT6A-20) was shut down. The pilot initiated a return to Pitt Meadows and turned the aircraft left for a landing at Runway o8R. With an indicated airspeed of 130 knots, the aircraft was headed back towards the runway. To maintain speed the left engine power lever forwarded to its maximum setting, however, the engine torque (indication for engine power) for the left engine decreased until also that engine failed. Both engines had now failed.
An attempt to restart the engines was initiated by placing both engine's auto-ignition switches in the on position, The restart attempt was unsuccessful. To maintain minimum airspeed the nose was lowered. However, this meant that the airport could not be reached. The aircraft touched down in a field of Cranberries, which was bordered by three feet berms. On landing, the aircraft struck several of the concrete irrigation culverts that lay on the edge of one of the berms. The aircraft bounced and struck the terrain again. On its second impact, the left wing dug into the soft peat, spinning the aircraft 180 degrees. The aircraft came to a stop ~400 meters from the airport. Four of the parachutists received serious injuries and the aircraft was substantially damaged. There was no fire and the occupants were evacuated. The emergency locator transmitter functioned at impact and was turned off by first responders.
The aircraft prior to the crash (Source baaa-arco.com © unknown)
An investigation into the accident was launched by the Transportation Safety Board of Canada (TSB). In their report (available for your reference by clicking here) the following findings as to cause and contributing factors are listed as a result of their investigation;
The general condition of the aircraft, the engine time before overhaul (TBO) over-run and the missed inspection items demonstrated inadequate maintenance that was not detected by regulatory oversight.
The TBO over-run and missed inspections resulted in excessive spline wear in the left engine-driven fuel pump going undetected.
The left engine lost power due to mechanical failure of the engine fuel pump drive splines.
The horizontal engine instrument arrangement and the lack of recent emergency training made quick engine malfunction identification difficult. This resulted in the pilot shutting down the wrong engine, causing a dual-engine power loss and a forced landing.
Not using the restraint devices contributed to the seriousness of injuries to some passengers.
Engine instrument layout (incident aircraft had horizontal layout (©TSB)
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