DENVER, CO, USA
N296WA
BOEING 727-247
THE LEFT MAIN LANDING GEAR COLLAPSED AS THE AIRCRAFT WAS PULLED FORWARD SLIGHTLY TO BRING THE NOSEWHEEL OFF THE CHOCKS PRIOR TO PUSHBACK. INSPECTION DISCLOSED A FRACTURE OF THE FORWARD TRUNNION BEARING SUPPORT FITTING (P/N 65-16206-11) AND HEAVY SURFACE CORROSION. MICROSCOPIC EXAMINATION DISCLOSED EXTENSIVE INTERGRANULAR STRESS CORROSION, AND A CRACK THAT HAD DEVELOPED 0.1 INCHES INBOARD FROM THE FORWARD EDGE OF THE BORE, WHICH HAD PROPAGATED APPROXIMATELY 2.1 INCHES AFT INTO THE BORE SURFACE. THE FINAL FRACTURE RESULTED FROM DUCTILE SEPARATION.
FAILURE OF THE LEFT MAIN LANDING GEAR FORWARD TRUNNION BEARING SUPPORT FITTING DUE TO A CRACK INITIATING AT THE FORWARD EDGE OF THE BORE AND PROPAGATING BY INTERGRANULAR STRESS CORROSION INTO THE BORE SURFACE THAT RESULTED IN AN EVENTUAL DUCTILE FRACTURE.
Source: NTSB Aviation Accident Database
Aviation Accidents App
In-Depth Access to Aviation Accident Reports
