What happened
On August 30, 2021, a student pilot was conducting short-field landing practice at the Melipilla Aerodrome (SCMP) in the Metropolitan Region of Chile. After an initial successful landing with an instructor on board, the student continued the training session solo. During the second of three planned circuits, the aircraft experienced a series of bounces on runway 26.
As the aircraft approached the runway, the pilot lowered the nose at a very low altitude. This maneuver, combined with a late flare, caused the main gear and the nose gear to contact the runway simultaneously. The resulting impact led to a condition known as porpoising, where the aircraft bounced twice before coming to a stop. While the pilot was uninjured and the aircraft was able to return to Curacaví Aerodrome, a subsequent inspection revealed significant structural damage.
The investigation
DGAC Chile investigators examined the aircraft at a hangar in Curacaví to assess the extent of the damage. The inspection revealed that the forward lower fuselage coverings were deformed and the firewall reinforcement and lower sections were both fractured and deformed. Additionally, rivets on the firewall bulkhead had been sheared. The investigation also noted that the engine and propeller had been removed during the inspection process to check for hidden damage.
Investigators reviewed maintenance records, which confirmed that the operator was compliant with all mandatory maintenance programs and that the aircraft's recent annual inspection was up to date. Meteorological data indicated that weather conditions were within visual flight rules (VFR) limits and did not contribute to the event. The investigation also noted that the incident was reported to the authorities 20 days after it occurred, which prevented the collection of real-time runway markings or debris evidence.
Findings
- The primary cause of the accident was an abnormal contact with the runway, where the main and nose landing gear struck the surface simultaneously, triggering a porpoising effect.
- A rapid change in aircraft attitude, characterized by a sudden nose-down movement after crossing the runway threshold, contributed to the instability.
- The pilot performed a late flare, which prevented the aircraft from establishing the proper landing attitude.
- The structural damage to the nose gear area was the direct result of high-energy impact loads that exceeded the capacity of the nose gear strut to absorb the force.