What happened
On August 5, 2002, at approximately 16:50 local time, a Cessna 172G, registration PT-CLU, operated by Aeroclube de São José do Rio Preto, was engaged in a flight for aerial photography of a sewage treatment plant. The flight originated from São José do Rio Preto.
Prior to the accident, the pilot landed at the Mirassol aerodrome to remove the aircraft doors to facilitate the photographer's work. Following this modification, the aircraft departed from the Mirassol dirt runway. During the takeoff roll, the aircraft struggled to climb. Upon reaching an altitude of approximately 400 feet, the aircraft entered a pre-stall condition. In an attempt to clear overhead high-voltage power lines, the pilot applied significant back pressure on the controls. This maneuver resulted in a loss of control, leading the aircraft to strike the ground, impacting the landing gear, left wing, and engine cowling before coming to rest in an inverted position.
The investigation
CENIPA investigators examined the engine, cylinders, and propeller, finding no mechanical failures in the powerplant or components. The investigation focused on the aircraft's performance capabilities under the specific environmental and operational conditions.
Investigators noted that the aircraft was operating at a high weight of approximately 1,025 kgf. While this was below the manufacturer's maximum takeoff weight (MTOW) of 1,043 kgf under ISA conditions, the performance was severely degraded by the high ambient temperature of 33°C, the use of a dirt runway, a tailwind component, and the increased parasitic drag caused by the removal of the aircraft doors. The investigation also noted that the pilot lacked specific training for aerial photography and had limited recent experience in this specific model.
Findings
- Improper decision-making: The pilot's decision-making was characterized by complacency and overconfidence, specifically regarding the decision to fly an unauthorized mission type and modify the aircraft configuration by removing the doors.
- Operational errors: The pilot failed to correctly evaluate the implications of taking off from a dirt runway with a tailwind and high temperature while the aircraft was effectively overweight for those specific environmental conditions.
- Flight planning failures: The flight plan included an excessive payload for the environmental conditions and an unauthorized mission type (aerial photography) for a primary training category aircraft.
- Inadequate configuration assessment: The removal of the doors increased parasitic drag, further compromising the aircraft's climb performance during a critical phase of flight.