NTSB: Boeing Extended MD-11 Inspection Interval 47% Before Deadly UPS Crash
Boeing extended MD-11 engine inspections from 19,900 to 29,260 cycles in 2015 despite seven reported steel-bearing flaws, allowing a UPS MD-11 with 21,043 cycles to avoid detailed checks before its engine detached, killing 15. The FAA approved Boeing’s request in one month without additional data, and three more failures emerged.
1. Extended Inspection Interval
In 2015 Boeing requested and received FAA approval to extend MD-11 engine inspection cycles from 19,900 to 29,260 flight cycles to reduce aircraft downtime. The proposal relied on older operational data and overlooked seven reported steel-bearing defects that could compromise engine mounts.
2. Crash Details and Oversight Gaps
The UPS MD-11 that lost its engine during takeoff at Louisville’s airport had flown 21,043 cycles, exceeding the original inspection threshold but not the extended interval; the failure killed three crew members and 12 ground bystanders. Deeply located bearing flaws went undetected without full engine removal and three additional failures surfaced after the interval change.
3. Regulatory and Safety Implications
The FAA’s one-month approval of Boeing’s inspection extension without seeking updated failure analyses highlights potential regulatory oversight lapses. The NTSB hearing is probing the shared safety responsibilities of Boeing, the FAA and airlines and potential revisions to MD-11 inspection protocols.