What happened
On October 9, 2017, a Beechcraft E33A, registration PT-DDB, was performing a private flight from Tangará da Serra, Mato Grosso, to São José do Rio Preto, São Paulo. The aircraft was carrying a pilot and two passengers.
As the aircraft approached runway 07 at São José do Rio Preto Airport, the pilot initiated a go-around procedure involving a right-hand turn. During this maneuver, the engine lost power, leading to a loss of control. The aircraft descended in a steep, nose-down attitude and struck a residential area approximately 400 meters to the right of the runway centerline. The impact caused substantial damage to the aircraft and a house in the area. All three occupants sustained fatal injuries.
The investigation
CENIPA investigators examined the wreckage and found that while the aircraft held a valid Certificate of Airworthiness, it was not in an airworthy condition due to unauthorized modifications. Investigators discovered a "cold start" reservoir at the crash site and corrosion within the engine's distributor valve. These findings suggested the engine had likely been modified to operate on ethanol rather than the standard AvGas, which would explain the corrosion and the need for the additional reservoir.
A checklist found at the scene indicated a fuel flow setting of 16 gallons per hour (GPH), which differs from the manufacturer's standard performance data. This higher consumption rate, combined with the flight distance, likely depleted the fuel reserves. Furthermore, investigators noted that the aircraft's maintenance logs were not up to date, with several flights appearing to have gone unrecorded.
Findings
- Inaccurate flight planning: The calculation of fuel consumption was incorrect, leading to the aircraft approaching the destination with fuel levels below the manufacturer's minimum requirements.
- Unauthorized engine modifications: The installation of a cold-start system and other modifications to the distributor valve were performed in violation of established aviation standards.
- Fuel exhaustion: The engine failure during the high-demand go-around maneuver was likely caused by fuel exhaustion, as the fuel lines and distributor were found empty.
- Pilot experience uncertainty: While the pilot held valid licenses, there was no documented evidence of recent experience in this specific aircraft type, which may have contributed to a lack of awareness regarding critical fuel limitations.