What happened
On July 1, 2009, a Cessna 172 RG, registration EC-HHY, was conducting a two-hour instructional flight departing from Córdoba Airport. After performing maneuvers during a local navigation flight north of Córdoba, the crew returned to the airport and entered the traffic pattern for runway 21.
During the final approach, the crew extended the landing gear and confirmed the green lights indicated the gear was down and locked. The initial touchdown was smooth on the main landing gear, and the aircraft taxied along the runway. However, as the aircraft transitioned to a nose-down attitude to support the nose gear, the nose strut failed to maintain support. This caused the propeller and the nose of the aircraft to strike the runway surface. The aircraft came to a stop approximately twenty meters further down the paved runway. The crew successfully shut down the engine and checked for fire; no injuries were reported to the two crew members.
The investigation
The investigation focused on the hydraulic-electric system and the mechanical operation of the landing gear retraction mechanism. Investigators examined the hydraulic pump, actuators, and the nose gear locking assembly. Testing confirmed that the hydraulic system had no leaks and that the mechanical components of the nose gear were in good condition. Repeated extension and retraction tests were performed, and the gear successfully locked in both the up and down positions.
While the investigation could not replicate the specific failure, investigators noted that the nose gear is the last component to lock during the extension sequence. Maintenance records showed no prior anomalies regarding the landing gear system.
Findings
- The investigation determined that the most probable cause was that the landing gear lever was operated only seconds before touchdown.
- Because the nose gear is the final part of the sequence to lock, the extension process had not been fully completed at the moment of impact.
- Upon touchdown, the resistance generated by the nose wheel contacting the runway surface was sufficient to overcome the hydraulic actuator's force, causing the nose gear to collapse while the main gear remained locked.