What happened
The aircraft, N4848Q, was loaded to its maximum gross weight and prepared for departure on a 2,350-foot turf runway. Before takeoff, the pilot noted that the wind was light and favored Runway 29. The density altitude was approximately 2,500 feet.
During the takeoff roll, the pilot observed that the aircraft did not seem to be developing the expected power, although the engine instruments indicated normal operation. The aircraft utilized the full length of the runway for liftoff but was unable to clear a fence located at the end of the strip. The aircraft struck the top of the fence and subsequently crashed into the field beyond.
After the accident, the pilot walked back to the airport and observed that the windsock indicated the wind was coming from the northeast, contrary to his earlier assessment.
The investigation
The investigation focused on the performance capabilities of the aircraft under the specific loading and environmental conditions. Examination revealed that the Cessna 150 was at its maximum gross weight limit, which significantly impacts acceleration and climb performance. The discrepancy between the pilot's perception of low power and the normal instrument readings suggested an aerodynamic or configuration issue rather than a mechanical failure.
Findings
Several factors contributed to the accident. The primary cause was the excessive aircraft weight combined with inadequate runway length for the conditions. The short turf surface likely increased rolling resistance, further reducing acceleration. Additionally, the pilot's misjudgment of wind direction and density altitude played a role in the decision to proceed with takeoff under suboptimal conditions.
Safety message
Pilots must carefully calculate weight and balance before every flight. Operating at maximum gross weight requires significantly longer takeoff rolls and results in poorer climb performance, especially on short or soft runways. Accurate assessment of wind direction and density altitude is critical for safe takeoff planning.