What happened
During the approach and landing phase of the flight, the crew attempted to extend the landing gear. While the gear deployment process was initiated, the cockpit indicators failed to show a down-and-locked status for the left main gear, as the green light remained unilluminated. In response to this discrepancy, the flight crew executed the established emergency checklists designed to address abnormal gear extension. Despite these efforts, the crew was unable to successfully lock the left main gear in the down position.
As a result of the mechanical failure, the aircraft completed its landing with the left main landing gear in the retracted position. Following the incident, a detailed mechanical inspection was conducted on the landing gear assembly to identify the source of the malfunction.
Findings
Post-incident investigations identified a specific component failure within the gear mechanism. The inspection revealed that a pin (part number MY20248-001), which functions as part of the forward gear door lock, had suffered from both corrosion and cracking at its rotation point. This structural degradation of the pin prevented the gear door uplock from moving correctly, which ultimately prevented the proper extension and locking of the left main landing gear.