What happened
On August 18, 1992, a Beech F 90-1 King Air, registered PT-OLP, was operating a flight from Itumbiara to Blumenau, with a scheduled stop in Ituverava. The flight was transporting two company directors. Due to deteriorating weather conditions at the destination of Blumenau, the crew diverted to Navegantes.
While descending, the crew canceled their IFR flight plan after reaching visual conditions above the cloud layer. However, as they approached Navegantes, the meteorological conditions deteriorated significantly, with visibility dropping to 2,000 meters and a ceiling of only 500 feet, placing the airport below the required minimums for IFR operations.
During the final approach for the NDB Echo 2 procedure, the crew reported the landing gear was down. Witnesses observed the aircraft performing a missed approach characterized by a steep 60-degree left turn at a low altitude (approximately 300 feet) while maintaining a landing configuration with flaps and gear extended. The aircraft then executed a steep reversal turn to the right. Shortly after, the aircraft disappeared into the horizon, followed by the sound of power being applied, before falling silent. The aircraft struck the sea approximately two kilometers from the runway threshold, resulting in four fatalities (two crew and two passengers) and the total loss of the aircraft.
The investigation
CENIPA investigators examined the wreckage, which was located nine meters deep in the ocean ten days after the accident. Physical analysis of the debris revealed the landing gear was extended at the time of impact. The investigation focused on the crew's decision-making regarding the flight plan cancellation and the execution of the approach under weather conditions below the minimums. Investigators also analyzed the flight profile, noting that the missed approach maneuver deviated from the established procedures outlined in the approach charts.
Findings
- Spatial disorientation was a highly probable physiological factor, as the crew performed high-bank maneuvers over the sea during heavy rain and restricted visibility, which eliminated ground references.
- Deficient judgment contributed to the accident, specifically regarding the decision to cancel the IFR flight plan while above the clouds and the decision to proceed with the approach to Navegantes while the airport was below minimums.
- Adverse meteorological conditions prevented the crew from achieving visual references during the approach.
- Flight indiscipline was noted due to the unauthorized cancellation of the IFR plan and the execution of a missed approach profile that did not follow the prescribed aeronautical charts.
- Potential psychological pressure or anxiety related to the mission of transporting company directors may have influenced the crew's decision-making.