What happened
During a local skydiving flight departing from Pitt Meadows Airport, British Columbia, a Beech 65-A90 King Air, registered N17SA, experienced a sudden engine failure while climbing through 3,900 feet. The pilot, carrying seven parachutists, noted a loud bang and a rightward yaw. In an attempt to return to the airport, the pilot initiated emergency procedures; however, the aircraft subsequently lost power from both engines.
Unable to reach the runway, the pilot performed a forced landing in a cranberry field approximately 400 metres west of the airport. During the landing sequence, the aircraft struck an earthen berm and several concrete irrigation culverts. The impact caused the aircraft to bounce and strike the terrain a second time, at which point the left wing embedded into the soft peat, spinning the aircraft 180 degrees. While there was no fire, four passengers sustained serious injuries.
The investigation
Investigators examined the aircraft's fuel systems and found no evidence of fuel exhaustion or contamination. While fuel starvation was considered, the fuel strainers and filters were functioning correctly. The investigation focused on the mechanical state of the engines and the pilot's response to the emergency.
Technical analysis revealed that the left engine's fuel pump drive splines had failed due to excessive wear and corrosion. This failure was not detected because the engine had been operated more than 800 hours beyond its required time before overhaul (TBO). Furthermore, the investigation found that the pilot had not received training on this specific aircraft type for over two years. The horizontal arrangement of the engine instruments contributed to the pilot's inability to quickly identify which engine had failed, leading the pilot to mistakenly shut down the remaining operational engine.
Findings
- The primary cause of the power loss was the mechanical failure of the left engine's fuel pump drive splines.
- Inadequate maintenance, characterized by exceeding engine TBO limits and missed inspections, allowed the spline wear to go undetected.
- The pilot's decision to shut down the functioning engine was driven by difficulty in identifying the malfunction due to the instrument layout and a lack of recent training.
- The severity of the passenger injuries was exacerbated by the fact that passengers were not wearing seat belts.
- Regulatory oversight by both the FAA and Transport Canada failed to identify the maintenance deficiencies.