What happened
On August 27, 2015, a Piper PA-3-2R-301T, registration PR-WTW, departed from the Aeródromo Nacional de Aviação (SWNV) in Goiânia, Brazil, for a local flight. The purpose of the flight was to verify the operational status of the autopilot and the landing gear. The aircraft had previously experienced a landing gear malfunction during a flight near Rondonópolis the day before, which had required the use of the emergency extension system.
Shortly after takeoff, the pilot noticed that the landing gear had failed to retract completely. Attempts were made to extend the gear using both the normal and emergency systems. While the main landing gear successfully locked in the down position, the nose gear (auxiliary gear) remained unlocked. The pilot proceeded to land with the nose gear unlatched. During the landing roll, the aircraft veered to the right and exited the runway, resulting in the propeller blades striking the ground. The aircraft sustained substantial damage, though both occupants escaped without injury.
The investigation
CENIPA investigators examined the aircraft's hydraulic systems and found a leak in a specific hydraulic line. Technical analysis performed by the Department of Aerospace Science and Technology (DCTA) revealed that the tubing had been improperly modified; the end of the tube lacked the required conical adjustment terminal. This modification prevented a proper seal, leading to the hydraulic leak that prevented the nose gear from extending and locking.
The investigation also noted that the pilot performed the emergency extension procedure at 110 knots, which was 20 knots above the manufacturer's recommended maximum speed of 90 knots for that procedure. Additionally, the pilot's emergency checklist was located in the baggage compartment rather than in the cockpit at the time of the incident.
Findings
- Inadequate maintenance and supervision of aircraft services, specifically the installation of a modified hydraulic line lacking the proper terminal.
- Improper execution of emergency procedures, as the pilot operated at a speed exceeding the manufacturer's limits for gear extension.
- Pilot attitude and judgment, characterized by a lack of adherence to safety precepts, including the failure to have the emergency checklist readily available in the cockpit.
- Limited flight experience, as the pilot had only 6 hours of flight time in this specific aircraft model.