What happened
On August 10, 2012, a Beechcraft 58, registration PT-WNM, operated by Tio Táxi-Aéreo, was performing a passenger transport flight departing from Flores Aerodrome (SWFN) in Amazonas, Brazil. During the takeoff roll on runway 11, as the aircraft approached rotation speed, the pilot noticed that the front cabin door had opened.
In response, the pilot initiated an aborted takeoff by reducing engine power and applying the brakes. During the deceleration, the aircraft began to skid. To maintain control and prevent the aircraft from leaving the runway, the pilot attempted a differential braking maneuver. However, the aircraft overran the runway, coming to a stop 4 meters beyond the stopway in a vegetated area. The pilot was uninjured, and the aircraft sustained no damage.
The investigation
CENIPA investigators examined the aircraft's maintenance history and the operational conditions at the time of the incident. The investigation revealed that during a flight earlier that same day, the same aircraft had experienced an inadvertent door opening, which required a landing for inspection. However, the pilot did not report this occurrence in the aircraft's logbook and simply re-closed and re-latched the door to continue the scheduled route.
Post-incident inspections of PT-WNM found that the door was not fully aligned with the fuselage and the upper latch was misadjusted, preventing the handle from reaching the fully locked position. While the pilot initially believed hydroplaning caused the loss of directional control, investigators ruled this out as there were no tire marks or brake wear consistent with such an event. The investigation also noted that the runway was wet due to recent rainfall.
Findings
- Aircraft maintenance: The upper latch mechanism was misadjusted, preventing proper door security.
- Instruction: The pilot was unaware of the specific emergency procedures outlined in the aircraft's Operating Manual regarding unlatched doors in flight.
- Management supervision: Failure to properly report and address the door malfunction following the previous flight's occurrence.