Aircraft Disintegration Over Miaoli County (B-2603)

Flight Details and Accident Sequence The aircraft departed Taipei-Songshan Airport with Kaohsiung as its destination. Approximately fourteen minutes after takeoff, while cruising at flight level 220, radar contact with the aircraft was lost. No distress message was transmitted by the crew. The aircraft subsequently entered an uncontrolled descent and experienced an explosive cabin decompression. It partially disintegrated in midair before crashing in Sanyi, Miaoli County. Debris was scattered over an area of approximately 10 square kilometers, and all 110 people on board were killed, including Japanese writer Kuniko Mukōda. ## Investigation Findings The official investigation identified extensive corrosion damage in the lower fuselage structures as the probable cause. This damage included corrosion that had penetrated through pits, holes, and cracks due to intergranular corrosion and skin thinning exfoliation corrosion. Additionally, the investigation noted the possible existence of undetected cracks resulting from the aircraft's high number of pressurization cycles, which totaled 33,313 landings. The interaction of these defects and damage had deteriorated to the point where rapid fracture occurred at a specific flight altitude and pressure differential. This led to rapid decompression and the sudden breakage of passenger compartment floor beams and connecting frames, which in turn cut control cables and electrical wiring. The sequence of events ultimately resulted in the loss of power, loss of control, and midair disintegration.