What happened
On September 1, 2020, a Tecnam P2008 JC, registration YL-EVA, was performing a 180-degree left turn at the start of runway 33 at Adazi Airfield. During this maneuver, the left-side attachment bracket for the nose gear failed. This structural failure caused the forward section of the airframe to tilt to the left, leading the propeller to strike the runway surface and resulting in the engine stopping. The aircraft sustained minor structural damage, including damage to the propeller blades, the engine lower cowling, and the nose gear attachment brackets. No injuries were sustained by the pilot or the passenger.
The investigation
The TAIIB investigation examined the aircraft's maintenance history and the physical properties of the failed component. The aircraft had recently undergone a 100-hour periodic maintenance check at Spilve Airfield, which was completed just days before the incident. Metallurgical analysis conducted by Riga Technical University revealed that the failure was a result of metal fatigue. The analysis showed that the crack originated at a point of maximum bending stress and progressed through several stages of fatigue development. The investigation also reviewed maintenance documentation, noting that the work release and the double-check procedures for the recent maintenance were signed by the same individual, which did not comply with the maintenance organization's manual.
Findings
- The primary cause of the incident was the inability of the nose gear structural design to withstand cyclic lateral impact loads.
- The direct cause was the failure of the left-side nose gear attachment bracket.
- The underlying cause was the progressive fatigue of the bracket material due to bending stresses from lateral dynamic loads.
- A prior hard landing on the nose gear had occurred but was not properly reported to the continuing airworthiness management organization (CAMO).
- There was insufficient attention paid to inspecting the nose gear assembly during the 100-hour maintenance interval.
- The aircraft was subject to intensive use for flight training, which contributed to the accumulation of fatigue cycles.
- Maintenance documentation for the recent 100-hour check contained procedural irregularities regarding the verification of completed tasks.