# The NTSB is focusing on fatigue cracks in the pylon bulkhead’s aft lug nut.

*aerospace · news · 2026-05-07 · FreightWaves*

## Key points

- Boeing altered the MD-11 bearing design by removing a lubrication groove and thickening the outer ring.
- FedEx will now replace MD-11 pylon bearings every 4,000 cycles and inspect them every 450 cycles.
- The FAA is not issuing ferry permits; FedEx is fixing grounded MD-11s at their current locations.
- FedEx developed ultrasonic and eddy current tests for earlier detection of bearing and ring fatigue cracks.
- As of now, repairs on two MD-11 aircraft are complete and awaiting FAA review for test flights.

**Companies:** Boeing, FedEx
**Countries:** United States

[Read the full story on FreightWaves](https://www.freightwaves.com/news/fedexs-md-11-comeback-to-start-with-short-cargo-flight-to-miami)

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