What happened
During the landing phase at the destination airport, the aircraft experienced a failure of the right main landing gear. As the gear collapsed, the right lower wing skin made contact with the runway, resulting in substantial structural damage to the airframe. Following the impact, the crew successfully brought the plane to a halt on the runway. An emergency evacuation was initiated, utilizing three of the four available exits.
During the evacuation process, the escape slide at the left forward door failed to deploy or inflate. Investigation revealed that the gas charge in the reservoir had been depleted. This depletion was caused by a leak within the valve assembly, a defect that had gone unnoticed during several inspections conducted since the slide assembly was installed on the aircraft.
Findings
Technical analysis determined that the landing gear cylinder fractured while subjected to standard landing loads. The failure was attributed to a fatigue crack located on the forward side of the cylinder. This specific area was subject to mandatory Airworthiness Directive (AD) inspections for cracks. Records indicate that the most recent inspection of the cylinder took place 218 landings prior to the accident, at which point the crack had grown to a size that should have been detectable. An even earlier inspection, conducted 497 landings before the event, failed to identify the crack when it was at a size that would have been marginally detectable.