Incident · 2024-05-14
What the record says
- Event date
- 2024-05-14
- Event type
- Incident
- Highest injury level
- No injuries
- Aircraft
- BOEING 787 (N27957)
- Operating rule
- Part 121
- Operator
- UNITED AIRLINES, INC. Operator named in NTSB report
- Operated by (per NTSB report)
- United Airlines
Probable cause
The uncontained left engine failure was caused by the failure and liberation of the HPT stage 1 aft blade retainer as a result of a fatigue crack in the upper collet radius that originated from a surface connected cluster of Oxide/Carbonitride/Nitride/Carbide (OCNC) particles. Contributing to the failure of the HPT stage 1 aft blade retainer was an unknown material behavior unique to OCNC clusters in Rene 65 material that are surface connected in highly stressed material that may result in a localized reduction of material fatigue life capability.
Source: NTSB case ENG24LA014Flight crew
No flight-crew details recorded in the NTSB accident database for this event.
Facts as the NTSB records them — GroundCheck adds no judgement. Preliminary records may be revised as the investigation proceeds.