What happened
On April 25, 2018, a private Piper PA-28R-201T, registration LV-MDO, was conducting a navigation flight from Matanza Aerodrome toward La Plata and Lobos when the pilot identified a malfunction. During the approach to La Plata, the pilot attempted to extend the landing gear, but the nose gear indicator remained unlit, signaling that the gear had not locked in the down position.
After attempting various troubleshooting procedures without success, the pilot returned to Matanza Aerodrome. To verify the gear status, the pilot performed a low pass over the airfield, allowing ground personnel to visually inspect the gear. Despite the visual confirmation that the gear appeared to be down, the pilot proceeded with an emergency landing on runway 17. Upon touchdown, the nose gear retracted immediately after making contact with the runway. The aircraft traveled approximately 230 meters before the propeller and the front of the fuselage struck the ground, eventually coming to a stop 300 meters from the runway threshold. There were no injuries to the occupants.
The investigation
The investigation focused on the mechanical failure of the nose gear locking mechanism. Upon inspecting the aircraft at the scene, investigators found that the nose gear was obstructed by a duct used to direct air from the engine cowling to the exhaust manifold for cabin heating. This duct was positioned in a way that interfered with the movement of the nose gear.
Further examination in a hangar revealed that the right steering roller had rubbed against the duct, causing it to deteriorate and fray. The investigation established that the wire from the damaged duct had become entangled with the steering mechanism. This entanglement prevented the nose gear locking hook from completing its full travel, meaning the gear was not securely locked in the down position. While the gear appeared extended, it was not mechanically engaged.
Findings
- The aircraft's heating duct obstructed the extension and retraction path of the nose gear.
- Friction from the right steering roller caused the duct to fray, leaving loose wires that interfered with the gear's locking mechanism.
- The nose gear failed to lock because the entanglement prevented the locking hook from fully engaging.
- The collapse of the nose gear was triggered by the physical impact and weight of the aircraft contacting the runway surface while the gear was unlocked.