# SDR AALA202604072466

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 2, 2026
- Submitted: April 7, 2026
- Operation: Air carrier
- Aircraft: [N418AN](https://openairdocs.org/aircraft/N418AN), registered now
- Make and model: Airbus A321-253NX
- Registry model: [Airbus A321-253NX](https://openairdocs.org/model/airbus-a321-253nx) (OpenAirDocs)
- Aircraft serial: 9550
- Aircraft time: 20,741 hours, 5,688 cycles
- System (JASC): [3510 · Crew Oxygen System](https://openairdocs.org/jasc/3510)
- Part: Union
- Condition: Stripped
- Location: Zone 200
- Stage of operation: CR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA202604072466

## Discrepancy

AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED AND THE AIRCRAFT DIVERTED TO PHX DUE TO THE FLIGHT CREW REPORTING THAT DURING CRUISE FIRST OFFICERS OXYGEN BOTTLE ECAM INDICATION DROPPED BELOW MINIMUM FLIGHT CREW REPORTED THAT IT INDICATED 490 AND KEPT DROPPING. THE AIRCRAFT LANDED SAFELY AT PHX WITH OUT FURTHER INCIDENT. THE FLIGHT CREW REPORTS THAT ON LANDING IN PHX THE INDICATION WAS 430. MAINTENANCE FOUND THE 3RD OBSERVER STORAGE BOX UNION TO BE STRIPPED / LEAKING AND REPLACED THE BOX PER AMM 35-12-41. A SATISFACTORY LEAK / OPERATIONAL CHECK WAS ACCOMPLISHED.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.