What happened
On October 21, 2011, an Aero Boero AB-115, registration PP-GAX, was conducting a local instructional flight at the Montenegro Aerodrome (SSNG) in Rio Grande do Sul, Brazil. The flight, operated by Aeroclube de Montenegro, carried an instructor and a student pilot.
During the flight, the instructor simulated an engine failure by reducing power to idle while the aircraft was positioned 90 degrees from the runway centerline. The student pilot attempted to manage the glide but, due to being misaligned with the runway, requested a go-around at 300 feet. The instructor overruled this request and decided to proceed with the landing.
As the aircraft approached the runway, a stall warning was heard. The instructor applied power and touched down abruptly on the runway. While attempting to use the brakes, the instructor lost control of the aircraft, causing the nose to strike the side of the runway and resulting in the aircraft capsizing. Both occupants survived the accident without injuries, though the aircraft sustained substantial damage.
The investigation
CENIPA's investigation revealed that the flight mission was not included in the aeroclub's official mission plan. Furthermore, the instructor failed to conduct a detailed pre-flight briefing as required by the Private Pilot Manual (MCA 58-3), instead coordinating the specific exercises while in flight.
Investigators noted that the instructor, while properly licensed, had only been serving as a flight instructor for three months and lacked significant experience in the role. The investigation also highlighted a breakdown in crew resource management, as the instructor's decision-making overrode the student's safety concerns regarding the unstabilized approach.
Findings
- Unstabilized approach: The aircraft was not properly aligned with the runway during the final approach.
- Poor decision-making: The instructor elected to proceed with the landing despite the student's request for a go-around and the presence of an unstabilized flight path.
- Lack of briefing: The absence of a formal mission briefing allowed for improvised and uncoordinated flight exercises.
- Inadequate crew dynamics: The instructor's decision-making superseded the student's assessment, creating a high-risk environment.
- Limited instructor experience: The instructor's recent certification as a flight instructor contributed to the error in judgment.
- Improper flight management: The mission was conducted outside of the established aeroclub mission plan.