What happened
On August 13, 2010, a Piper PA-23-160, registration PT-BFA, was operating a flight from São José dos Campos, SP, to Goiânia, GO, carrying an instructor and a student. Approximately two hours and 50 minutes into the flight, while near the Anápolis Terminal, the right engine failed. The pilot declared an emergency and requested priority landing at Goiânia Airport (SBGO).
During the approach to runway 32, approximately 10 nautical miles from the airport, the left engine also failed. This second failure forced the crew to perform an emergency landing in an open field near the Portal do Sol residential area. The aircraft sustained severe damage to the wings and the lower fuselage after striking a termite mound, but both occupants emerged uninjured.
The investigation
CENIPA's investigation focused on the cause of the simultaneous engine failures. Investigators found that the aircraft's fuel tanks were deformed, which had reduced their capacity. While the aircraft had been fueled for the trip, a significant fuel leak was present in the right tank.
Upon inspection, investigators found no remaining fuel in the tanks or the fuel system. The investigation also reviewed the maintenance history, noting that a 50-hour inspection had been performed 23 days prior to the accident. Furthermore, the investigation examined the operator's safety management, finding that the flight crew was using a pre-flight checklist that did not include all the external inspection items required by the manufacturer.
Findings
- The primary cause of the accident was fuel exhaustion (pane seca) caused by a continuous leak in the right fuel tank.
- The failure of the first engine (right) occurred due to the depletion of fuel caused by the leak.
- The failure of the second engine (left) occurred because the crew applied maximum power to the remaining engine to maintain flight, which significantly increased the fuel consumption rate, leading to the depletion of the remaining fuel approximately 15 minutes later.
- A failure to properly execute the 50-hour inspection likely allowed the leak to go undetected.
- The use of an incomplete pre-flight checklist prevented the crew from noticing fuel stains on the underside of the wing.
- Organizational deficiencies at the flight school, including a lack of flight safety supervision and the absence of a qualified flight safety officer, contributed to the maintenance and operational lapses.