What happened
On June 9, 2019, a Piper PA-28-200, registration LV-LMG, was performing a local training flight at the Los Toldos aerodrome in Buenos Aires, Argentina. During the landing roll on runway 05, the nose landing gear unexpectedly began to retract. This movement caused the propeller to strike the ground, resulting in significant damage to the propeller and the lower engine cowling. The aircraft came to a stop on the runway, and the occupants were able to exit the aircraft without any injuries.
The investigation
The investigation examined the aircraft's landing gear system and the physical condition of the components. Investigators inspected the nose gear hydraulic cylinder, which was found to be broken, and noted the damage to the propeller. During testing, the landing gear's cockpit indication lights were found to be functioning correctly, showing three green lights when the gear was manually set to the down position.
However, a critical discrepancy was discovered regarding the nose gear locking mechanism. The installed locking hook did not match the design illustrated in the aircraft's official parts catalog or service manual. Specifically, while the manufacturer's plans for the part required three bolts, the component installed on LV-LMG only featured two. No documentation or traceability was found to justify the use of this non-standard part, nor was there any record of an approved replacement.
Findings
- The exact origin of the mechanical failure could not be definitively determined.
- The nose gear locking hook installed on the aircraft did not match the specifications provided in the applicable parts catalog.
- There was no evidence or technical traceability regarding the installation or approval of the non-standard locking hook.