What happened
On February 22, 2017, a Piper PA-34-200 (registration PR-FLM) was conducting a navigation training flight departing from Florianópolis Airport (SBFL). The flight plan included touch-and-go maneuvers at Joinville (SBJV) and Navegantes (SBNF). Upon returning to SBFL, the crew decided to perform an unbriefed training exercise involving a simulated single-engine failure on the base leg of runway 03.
During the maneuver, the instructor reduced power on the left engine to simulate a failure. The student pilot, who was undergoing multi-engine transition training, struggled to maintain heading and altitude. Consequently, the instructor took control of the aircraft on the final approach. During this transition, the landing gear was not extended, and the aircraft subsequently performed a landing with the gear retracted, resulting in substantial damage to the aircraft. Both occupants emerged uninjured.
The investigation
CENIPA's investigation focused on the crew's coordination and the aircraft's mechanical state. Investigators found that the training exercise was not included in the original flight instruction order, nor was it discussed during the pre-flight briefing. The investigation also examined the aircraft's landing gear warning system, which failed to alert the crew to the retracted state during the power reduction.
Technical analysis revealed that a microswitch in the throttle quadrant was improperly adjusted. While the landing gear horn functioned normally under standard power settings, the switch lost contact when the throttles were moved to the IDLE position. This mechanical issue silenced the warning alarm exactly when the crew needed it most during the simulated failure.
Findings
- Inadequate crew coordination and cockpit dynamics led to a breakdown in standard operating procedures.
- The instructor failed to perform the landing checklist after assuming control of the aircraft.
- The training exercise was conducted without a proper briefing, contributing to the student's difficulty in maintaining aircraft control.
- A mechanical adjustment error in the throttle microswitch prevented the landing gear warning horn from activating when the engines were at idle.
- The flight school's training philosophy, which relied on a single-pilot approach for checklists, contributed to the oversight when the instructor took command.
Safety action
CENIPA issued recommendations to the National Civil Aviation Agency (ANAC) to promote the importance of strict checklist adherence among pilots and flight schools. Additionally, recommendations were made to the operator to enhance Crew Resource Management (CRM) training and ensure that all flight exercises are thoroughly briefed to mitigate errors during student maneuvers.