What happened
On March 2, 2014, at 16:20 UTC, a Cessna 150L, registration PT-OYF, was conducting a touch-and-go training flight near Atibaia, São Paulo. The aircraft had departed from Fazenda Vale Eldorado for its second flight of the day. Approximately 50 minutes into the flight, the engine suffered a power loss, forcing the pilot to perform an emergency landing in an unprepared, irregular field.
During the landing sequence, the aircraft's wingtip struck a tree, and the nose landing gear collapsed due to the uneven terrain. The impact resulted in substantial damage to the engine, propeller, wings, and fuselage. The pilot emerged from the accident uninjured.
The investigation
The investigation focused on the fuel levels and flight planning parameters. Investigators determined that the aircraft had been fueled with only 30 liters of AVGAS for the day. Upon inspection of the wreckage, approximately 7 liters of fuel were found remaining in the wing tanks (4 liters in the left tank and 3 liters in the right tank).
It was noted that the flight school's practice was to use a fuel consumption estimate of 20 liters per hour, which is lower than the 22 liters per hour specified in the aircraft's Flight Manual. Furthermore, the school's own safety procedures recommended fueling the Cessna 150L with a minimum of 40 liters for local flights. Because the Cessna 150L lacks a fuel selector valve, the depletion of one tank can allow air into the fuel lines, causing intermittent fuel delivery to the carburetor and subsequent engine power degradation.
Findings
- Inadequate flight planning regarding fuel reserves.
- Deficient managerial supervision regarding fueling and consumption estimates.
- The pilot utilized a fuel consumption rate (20 L/h) that was lower than the manufacturer's specification (22 L/h).
- The total fuel loaded (30 liters) was insufficient for the total flight time of the day, which included a prior one-hour flight.