The Captain reported a normal flight and that the landing approach was stabilized. He stated that the wind was 'right down the runway for the landing.' As the airplane decelerated through 70 KIAS, the first officer reported hearing a 'loud bang,' and the airplane began 'listing heavily to the right and drifting to the right.' The pilots determined that the right main landing gear (MLG) had collapsed and an evacuation was ordered. The right MLG was last removed (18,188 cycles before the accident) for overhaul on April 8, 1988, and the right MLG forward trunnion bearing support fitting (FTBSF) was last ultrasonically inspected in May 1993 (7,634 cycles before the accident). A Service Bulletin, dated March 8, 1990, recommended that the MLG FTBSFs be ultrasonically inspected after 12,000 flight cycles every 6 months or 1,500 flight cycles, whichever occurred first. Operators were to continue this inspection cycle until the part was replaced or the preventative modification was done. The NTSB Materials Laboratory examined the broken right MLG FTBSF and determined that the failure was the result of stress corrosion cracking.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:

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