What happened
On December 14, 2017, a Zenair Alarus CH2000, registration OB-2143, was conducting a local flight instruction mission at the Las Dunas Aerodrome in Ica, Peru. The flight, operated by the Jorge Chávez Dartnell S.A. flight school, was being conducted by an instructor pilot and a student pilot as part of a flight training lesson.
After completing several successful takeoff and landing maneuvers, the aircraft was on its final approach for a landing on runway 33. During the flare maneuver, the student pilot abruptly pushed the flight controls forward. This sudden movement caused the nose gear to make contact with the runway before the main landing gear. The impact caused the nose gear assembly to fail, specifically fracturing the mounting bolts, which led to the nose wheel detaching from the aircraft. The resulting impact caused the rotating propeller to strike the runway, resulting in damage to the propeller, the engine, and the lower engine cowling.
The aircraft came to a stop approximately 80 meters from the runway threshold. Both the instructor and the student pilot evacuated the aircraft safely and sustained no injuries.
The investigation
The CIAA investigation examined the flight sequence, the mechanical condition of the nose gear, and the crew's actions. Investigators reviewed the student pilot's training records, which showed he was in the "Pre-Solo" phase of instruction. Meteorological reports (METAR) indicated that weather conditions were optimal and did not show any wind gusts at the time of the accident, contradicting the student pilot's perception of a wind gust.
Mechanical analysis of the nose gear revealed that the failure of the mounting bolts was due to shear forces that exceeded their design strength during the impact. Additionally, investigators noted evidence of pitting corrosion on the bolts, suggesting they had been exposed to a corrosive environment or had not been sufficiently inspected during recent maintenance.
Findings
- The student pilot's sudden forward control input during the flare caused the nose gear to strike the runway first.
- The instructor pilot experienced a loss of situational awareness, which prevented him from intervening in time to correct the student's erroneous maneuver.
- The impact caused the failure of the nose gear mounting bolts and the subsequent detachment of the nose wheel.
- The student pilot's reaction was likely triggered by a perceived wind gust that was not supported by meteorological data.
- There was evidence of corrosion on the nose gear mounting bolts.