What happened
On September 13, 1996, at approximately 22:28 UTC, a BE 58, registration PT-OYH, departed Bacacheri Airport in Curitiba, Brazil, bound for Campo Grande. The flight was operating under Instrument Flight Rules (IFR) in night conditions with low ceilings, drizzle, and light turbulence.
Shortly after takeoff, while executing the EROM 2 climb procedure, the pilot was instructed to turn left to intercept the CTB VOR radial 005. However, air traffic controllers observed via secondary radar that the aircraft was actually performing a right turn, deviating from the assigned path and creating a potential conflict with other traffic. When questioned, the pilot reported being on radial 004 with a heading of 150°, a significant deviation from the required course. Following the controller's instruction to correct the course, radio contact was lost. The aircraft subsequently struck the ground approximately 5 km from the airport in a near-vertical, 90-degree nose-down attitude. The impact caused a post-crash fire, and all five fatalities (one pilot and four passengers) were confirmed at the scene.
The investigation
CENIPA's investigation focused on the pilot's physiological state, the aircraft's mechanical condition, and the operational environment. The investigation established that the engines and propellers were in normal operating condition and that the aircraft's maintenance was up to date.
Investigators examined the pilot's recent work history, noting that he had been awake for approximately 13.5 hours and had only received five hours of sleep the previous night. Furthermore, the pilot had requested assistance to fill out his flight plan because he felt too exhausted to do so himself. The investigation also noted that the operator lacked a dedicated operations department to supervise flight schedules and pilot fatigue.
Findings
- Pilot fatigue was a primary contributing factor, as the pilot was operating under significant physiological stress and sleep deprivation.
- Spatial disorientation likely occurred during the IFR climb, leading to the incorrect execution of the departure procedure and the loss of situational awareness.
- Adverse meteorological conditions, including night flight and low visibility (IMC), prevented the pilot from using external visual references to recover from the deviation.
- Deficient flight planning was noted, as the pilot had not adequately reviewed the weather conditions for the route or destination prior to departure.
- Inadequate operational supervision by the operator, which failed to monitor the pilot's excessively long duty periods and lack of rest.