What happened
On August 15, 2004, a Beechcraft A36, registration PT-LBH, departed Araguaína, TO, bound for Gurupi, TO, for a passenger transport flight. The aircraft was operated by a private owner and carried a pilot and two passengers. The flight was conducted under Visual Flight Rules (VFR) with full fuel tanks, and the crew intended to make a refueling stop in Gurupi before continuing to Goiânia.
No flight plan was filed, and no radio contact was established with Air Traffic Services (ATS) during the flight. When the aircraft failed to arrive at its destination, the families of the passengers alerted the Manaus Rescue Coordination Centre (RCC-MN). Search operations began the following day, leading to the discovery of the wreckage near Fazenda Fagund and approximately 15 minutes of flight time from the Gurupi aerodrome. The impact resulted in three fatalities (the pilot and two passengers) and the complete destruction of the aircraft.
The investigation
CENIPA investigators examined the highly fragmented wreckage, which was scattered across an area of approximately 1 km². The investigation revealed that the aircraft's primary components, including the engine and wings, were widely separated, with some parts found up to 1,800 meters from the main wreckage. Analysis of the engine and propeller indicated that the engine was without power at the moment of impact, and the fuel gauges were in the empty position.
Structural analysis of the wreckage showed that the horizontal stabilizers and the wings had undergone vertical deformation and bending beyond their structural limits, eventually resulting in separation from the fuselage. Investigators also noted the presence of moderate turbulence in the region due to high temperatures (32°C to 35°C). While the pilot was a qualified commercial pilot, records indicated no previous flight experience in this specific high-performance aircraft type.
Findings
- Inappropriate control inputs: The investigation suggests the pilot applied abrupt and excessive elevator commands, causing the aircraft to exceed its structural G-load limits.
- Lack of aircraft familiarization: The pilot had no recorded flight hours in the Beechcraft A36 prior to the accident, which may have prevented an adequate response to abnormal flight conditions.
- Operational non-compliance: The pilot failed to file a flight plan or maintain contact with ATS, which delayed the initiation of search and rescue operations.
- Environmental factors: The presence of moderate turbulence or a sudden maneuver to avoid birds were considered possible triggers for the initial loss of control.
- Structural failure: The sequence of events likely involved the failure of the horizontal stabilizers followed by the structural failure of the wings due to extreme load factors.