# SDR DALA2026051703034

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 15, 2026
- Submitted: May 17, 2026
- Operation: Air carrier
- Aircraft: [N334DN](https://openairdocs.org/aircraft/N334DN), registered now
- Make and model: Airbus A321-213
- Registry model: [Airbus A321-213](https://openairdocs.org/model/airbus-a321-213) (OpenAirDocs)
- Aircraft serial: 8040
- Aircraft time: 26,430 hours, 11,514 cycles
- System (JASC): [4920 · APU Core Engine](https://openairdocs.org/jasc/4920)
- Part: Apu
- Condition: Fumes
- Location: Zone 100
- Stage of operation: AP
- How discovered: O
- Nature of condition: C, B
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DALA2026051703034

## Discrepancy

DECLARED EMERGENCY DUE TO FUMES IN THE COCKPIT PASSING THROUGH FL190 DURING THE APPROACH. DONNED OXYGEN MASKS AND CONTINUED TO DFW.   APU WAS PREVIOUSLY DEFERRED FOR LOAD COMPRESSOR CONTAMINATION. DFW MAINTENANCE FOUND APU CONTROL C/B PUSHED IN, ALLOWING APU TO RUN. SUSPECT APU WAS RUN DURING AIRCRAFT MOVE TO THE GATE PRIOR TO DEPARTURE FROM ATL. PERFORMED NO-GO ECS DECONTAMINATION. APU DEACTIVATED AGAIN. APU LATER REPLACED. (LP 8532928, 8532926 - AIRCRAFT WAS GROUNDED).

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