What happened
On a summer afternoon at the Calling Lake aerodrome in Alberta, a Cessna 177B Cardinal was preparing for a scheduled flight to Lloydminster. The flight, a commercial operation, was intended to transport a passenger who had been delivered to the airstrip by helicopter.
As the aircraft began its takeoff roll on runway 10, it faced challenging conditions, including a grass runway surface, an uphill slope, and significant crosswinds. Shortly after becoming airborne, the aircraft's stall warning horn activated. The left wing dropped abruptly, and the plane struck a line of 30-foot-tall trees located in an unmaintained clearway zone just past the runway end. The impact triggered an intense, fuel-fed fire that quickly consumed the aircraft. While the passenger managed to extricate himself and escape with serious burns, the pilot succumbed to the thermal effects of the fire. The accident also ignited a small forest fire in the surrounding area.
The investigation
Investigators examined the aircraft's mechanical condition, the aerodrome's infrastructure, and the pilot's performance. The engine and flight controls showed no signs of malfunction prior to the impact, and the aircraft was found to be within its weight and balance limits.
Technical analysis focused on the aircraft's fuel system design. The investigation noted that the Cessna 177B featured a "wet wing" design and fuel components, such as the gascolator and carburetor, were positioned in areas vulnerable to impact damage. The investigation also looked into the runway environment, noting that the clearway at the end of runway 10 had not been cleared of vegetation since 1985, allowing trees to grow into the departure path.
Findings
- The aircraft entered a stall at an altitude that made recovery impossible.
- The pilot likely failed to maintain the required best-angle-of-climb speed during the departure.
- The pilot likely attempted the takeoff without flaps to better manage the crosswind, which increased the required ground roll and climb distance.
- The post-crash fire was fueled by leaking fuel from components damaged during the impact.
- The presence of tall trees in the departure clearway contributed to the collision.
- The pilot likely would have survived the initial impact had the post-crash fire not occurred.