What happened
On a multi-leg cargo flight traveling from Vancouver toward Nanaimo and Victoria, the Piper PA-31-350 Chieftain, registered as C-GNAF, was operating under visual flight rules. During the final stage of its journey, the aircraft was positioned on the approach to Runway 26 Right at Vancouver International Airport. The flight was following a larger Airbus A321 and was approximately 1.5 nautical miles behind and 700 feet below the heavier jet's path when it turned onto the final approach course.
At 22:08 PDT, the aircraft disappeared from tower radar surveillance. The plane struck the ground within an industrial zone in Richmond, British Columbia, roughly 3 nautical miles from the runway threshold. The impact was followed by a fire and explosion. There were 2 fatalities among the crew members on board. While the crash caused damage to property on the ground, no individuals on the surface were injured. Due to the destruction of the emergency locator transmitter, no distress signal was received.
Findings
Investigations concluded that the primary cause of the accident was that the aircraft entered the wake turbulence area created by the preceding heavy aircraft. This encounter caused an upset and a subsequent loss of control at an altitude that left the crew with no opportunity to recover the plane. The investigation noted that the speed of the trailing traffic forced the aircraft into a position where it could not maintain sufficient separation from the heavier jet.
Additional contributing factors included concerns regarding the adequacy of current wake turbulence separation standards and the limitations of relying on visual separation during nighttime operations. Furthermore, investigators identified risks related to potential pilot fatigue due to unregulated duty times outside of aviation duties. The study also noted that a lack of cockpit recording devices prevented a full reconstruction of the crew's decision-making processes.