What happened
On November 25, 2022, a Cessna 152, registration LV-BRF, was conducting a solo flight training maneuver at the General Rodríguez aerodrome in Buenos Aires province. The flight, operated by Flight Center, was part of a review session for a student pilot. After an initial approach with an instructor on board, the instructor disembarked, leaving the student to perform solo landing circuits.
During the first solo landing attempt, the aircraft experienced an abnormal contact with the runway. The impact triggered a sequence of six increasing bounces. This longitudinal instability caused the nose gear to collapse, resulting in the aircraft overturning. The student pilot sustained one minor injury, and the aircraft suffered significant damage.
The investigation
Investigators examined the aircraft and the runway conditions. While the student pilot initially suggested that a pothole on the runway caused the right wheel to strike an obstacle, a physical inspection of the runway revealed no such defects or obstructions.
Technical analysis of the nose gear assembly, specifically the fork and wheel, showed that the fracture was caused by the sudden application of loads exceeding the component's design limits. No pre-existing metallurgical or mechanical defects were found in the part. Furthermore, while the aircraft was equipped with a Dynon EFIS D-100, the software version prevented the retrieval of flight parameters from its internal memory. However, security camera footage provided a visual record of the aircraft's trajectory, confirming the series of bounces.
Findings
- The aircraft entered a state of divergent longitudinal oscillation, known as "porpoising," following the initial contact with the runway.
- The nose gear failed due to the rapid application of structural overloads during the repeated impacts.
- The student pilot's attempts to correct the pitch through elevator inputs likely contributed to maintaining and increasing the magnitude of the oscillations.
- A safety risk was identified regarding the lack of a pre-flight briefing between the instructor and the student prior to the solo maneuver.
Safety action
- It is essential for pilots to understand the factors contributing to abnormal runway contacts and to be trained in specific recovery techniques, such as managing bounces or executing a go-around/escape maneuver.