What happened
On January 23, 2016, an Aero Boero AB-115, registration PP-FGQ, was conducting a local instructional flight at the Bacacheri Aerodrome (SBBI) in Curitiba, Brazil. The flight was part of a Commercial Pilot training course operated by Aeroclube do Paraná, carrying an instructor and a student pilot.
After performing two landings on runway 36, the air traffic controller instructed the crew to cross the aerodrome and enter the traffic pattern for runway 18, requesting a shortened base leg. During this maneuver, the instructor directed the student to perform a simulated engine failure training exercise, which involved reducing engine power to idle. As the aircraft prepared for touchdown, it began to veer to the right. The student attempted to correct the direction using the rudder pedals, but the maneuver was unsuccessful due to a loss of rudder effectiveness. The instructor attempted to intervene, but the aircraft exited the runway and collided with a drainage ditch. The aircraft sustained light damage, and both occupants were unharmed.
The investigation
CENIPA's investigation focused on the training procedures and the operational characteristics of the aircraft. Investigators found that the student was performing the sixth mission of an adaptation phase, but the training syllabus had not been strictly followed. Specifically, the simulated engine failure exercise, which was scheduled for an earlier mission (AD-04), had not been previously conducted. Furthermore, the exercise was not included in the pre-flight briefing.
The investigation also noted the unique handling characteristics of the AB-115. The aircraft utilizes a braking system operated by the heels rather than the toes, and its conventional landing gear configuration—with a short distance between the main wheels and the tailwheel—makes directional control difficult during ground operations, especially under engine torque. No mechanical abnormalities were found in the flight controls or braking systems.
Findings
- Instructional deficiencies: The training program was not properly adhered to, as the student was performing advanced maneuvers without the required prior progression or adequate briefing.
- Inadequate command application: The loss of directional control during the landing roll was likely due to improper use of the rudder pedals during the simulated power reduction.
- Aircraft characteristics: The inherent difficulty in maintaining directional control on the ground in the AB-115 contributed to the excursion.
Safety action
CENIPA issued a recommendation to the National Civil Aviation Agency (ANAC) to work with the operator to ensure flight instruction processes align with official manuals, specifically regarding evaluation forms and the necessity of comprehensive pre-flight briefings for all maneuvers.