What happened
On February 22, 2020, a Piper PA-42-720, registration PR-DDQ, was performing a charter flight from São Paulo (SBSP) to Curitiba (SBBI) after transporting a patient. During the approach to the destination, the crew noticed that the nose landing gear failed to fully extend and lock into position.
The crew decided to hold and requested a low pass over the Afonso Pena Airport (SBCT) to allow Air Traffic Control to visually inspect the gear. Controllers confirmed that the nose gear was not locked. Consequently, an emergency situation was declared, and the aircraft performed a landing at SBCT. The aircraft sustained light damage, and all four occupants—two crew members and two passengers—were uninjured.
The investigation
CENIPA investigators examined the aircraft's landing gear assembly following the incident. The inspection revealed that the landing gear command link (PN 75178-02) had broken. A technical analysis of the fractured component showed characteristics consistent with a failure due to overload, with no evidence of corrosion or fatigue present on the fracture surfaces.
Findings
- The primary cause of the gear failure was the breakage of the landing gear command link due to an applied overload.
- It is hypothesized that the component may have been compromised by excessive loads during a previous landing, which eventually led to the failure when hydraulic pressure was applied during the flight in question.
- The broken link prevented the nose gear from fully extending and locking, necessitating the diversion to an alternate airport.