What happened
On September 24, 2014, an Aero Boero AB-115, registration PP-GAF, was conducting a flight as part of a Commercial Pilot Course. The flight originated from Belém Novo Aerodrome in Porto Alegre, RS, with a planned route to Centeno Aerodrome in Tapes, RS, and a return to the departure point. On board were an instructor and a student pilot.
During the return leg of the flight, the instructor took control of the aircraft and performed a low-level pass over a rural area in the municipality of Barra do Ribeiro, RS. During this maneuver, the aircraft collided with electrical wiring. The crew did not immediately notice any damage to the aircraft and continued the flight back to Belém Novo. The collision resulted in no injuries to the occupants, though the aircraft sustained light damage to the propeller and fuselage.
The investigation
CENIPA's investigation established that the flight was being conducted under Visual Flight Rules (VFR). Both the instructor and the student pilot held valid medical and technical certificates, and the instructor was highly qualified with 450 total flight hours. The aircraft was also in a fully airworthy condition, with valid maintenance records and proper weight and balance.
The investigation revealed that the low-altitude flight performed by the instructor was not a requirement of the Commercial Pilot Course curriculum. Furthermore, the crew failed to report the incident to the authorities or the flight club immediately after the event. The damage to the aircraft went unnoticed for several subsequent training flights, only being discovered by the Aeroclube during routine maintenance. It was also noted that the flight club conducted an internal investigation before notifying the investigating authority.