# SDR F3LA201909100112

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 9, 2019
- Submitted: September 10, 2019
- Operation: Air carrier
- Aircraft: [N723FR](https://openairdocs.org/aircraft/N723FR), registered now
- Make and model: Airbus A321-211
- Registry model: [Airbus A321-211](https://openairdocs.org/model/airbus-a321-211) (OpenAirDocs)
- Aircraft serial: 08640
- Aircraft time: 2,651 hours, 1,102 cycles
- System (JASC): [3510 · Crew Oxygen System](https://openairdocs.org/jasc/3510)
- Part: Oxygen Mask
- Part number: MF20534
- Part serial: B140322
- Condition: Broken
- Location: Cockpit
- Part time: 2,651 hours, 1,102 cycles
- Stage of operation: IN
- How discovered: C
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/F3LA201909100112

## Discrepancy

CAPTAINS O2 MASK MAIN HOSE CAME OFF DURING PREFLIGHT SYSTEM CHECK. SWAP PILOTS O2 MASK W/4TH OBSERVER MASK OP CHECKS NORMAL AIRCRAFT OK TO CONTINUE. 4TH OBSERVERS O2 MASK INOP. DEFERRED PER MEL 25-11-07A CT# 1154512 DUE DATE 07-07-2020.

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