Summary
On March 31, 1993, a Boeing 747-121 (N473EV) was involved in an incident near Anchorage, AK. All 5 people aboard were uninjured. The aircraft sustained substantial damage.
The National Transportation Safety Board determined the probable cause of this incident to be: THE LATERAL SEPARATION OF THE NO. 2 ENGINE PYLON DUE TO AN ENCOUNTER WITH SEVERE OR POSSIBLY EXTREME TURBULENCE THAT RESULTED IN DYNAMIC MULTI-AXIS LATERAL LOADINGS THAT EXCEEDED THE ULTIMATE LATERAL LOAD-CARRYING CAPABILITY OF THE PYLON, WHICH WAS ALREADY REDUCED BY THE PRESENCE OF THE FATIGUE CRACK NEAR THE FORWARD END OF THE PYLON'S FORWARD FIREWALL WEB.
SEE NTSB BLUE COVER AVIATION ACCIDENT REPORT AAR-93-06 FOR FURTHER INFORMATION.
This incident is documented in NTSB report DCA93MA033. AviatorDB cross-references NTSB investigation data with FAA registry records to provide comprehensive safety information for aircraft N473EV.
Accident Details
Probable Cause and Findings
THE LATERAL SEPARATION OF THE NO. 2 ENGINE PYLON DUE TO AN ENCOUNTER WITH SEVERE OR POSSIBLY EXTREME TURBULENCE THAT RESULTED IN DYNAMIC MULTI-AXIS LATERAL LOADINGS THAT EXCEEDED THE ULTIMATE LATERAL LOAD-CARRYING CAPABILITY OF THE PYLON, WHICH WAS ALREADY REDUCED BY THE PRESENCE OF THE FATIGUE CRACK NEAR THE FORWARD END OF THE PYLON'S FORWARD FIREWALL WEB.
Aircraft Information
Registered Owner (Historical)
Analysis
SEE NTSB BLUE COVER AVIATION ACCIDENT REPORT AAR-93-06 FOR FURTHER INFORMATION.
Data Source
Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# DCA93MA033