What happened
On May 24, 2011, an EMB-110P1, registration PT-SHU, was performing a takeoff from Urucu Aerodrome (SBUY) in Coari, Amazonas, destined for Tefé. The aircraft was operating as a non-scheduled public transport flight, carrying two pilots and thirteen passengers.
During the takeoff roll on runway 27, the co-pilot, acting as the pilot flying, reported that the control column became unresponsive when attempting to rotate the aircraft. The commander took control of the aircraft but also found that the pitch controls were not responding effectively. In an attempt to generate enough lift to depart the ground, the commander commanded the flaps to the 100% position.
As the aircraft failed to rotate, the commander eventually decided to abort the takeoff. However, the aircraft exceeded the runway limits and came to a stop 663 meters beyond the opposite threshold. The aircraft sustained substantial damage, including broken nose and left main landing gear, damage to the left wing, and bent propeller blades. All 15 occupants (two crew and thirteen passengers) were uninjured.
The investigation
CENIPA's investigation focused on the sequence of events during the takeoff roll and the crew's decision-making process. Investigators examined the aircraft's maintenance records, which showed the plane had undergone a 150-hour inspection only 38 flight hours prior to the accident. The investigation also reviewed the flight crew's experience and the operational environment.
Technical analysis of the flight controls revealed no abnormalities in the flight control systems or the autopilot. While the flaps were found to be at 80% following the event, the investigation explored the possibility that they may have been set to 100% during the roll, which would have significantly degraded takeoff performance. The investigation also considered the possibility of an incorrect elevator trim setting, though this was deemed unlikely.
Findings
- Inadequate pilot judgment: The decision to command full flaps to 100% during a perceived control malfunction, rather than immediately aborting, was a critical factor that exacerbated the situation.
- Delayed decision-making: The crew failed to abort the takeoff immediately when the control issue first manifested, leading to the runway excursion.
- Improper use of controls: Using the 100% flap setting as an emergency procedure during takeoff does not correspond to any established emergency procedures for the aircraft and increased the takeoff distance required.
- Potential checklist errors: There were indications of possible deficiencies in cockpit coordination and checklist execution, specifically regarding the verification of flap settings.
- Organizational factors: The investigation noted potential issues regarding training resistance within the organization and a lack of standardized training oversight.