# SDR AALA202607305439

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 29, 2026
- Submitted: July 30, 2026
- Operation: Air carrier
- Aircraft: [N907NN](https://openairdocs.org/aircraft/N907NN), registered now
- Make and model: Boeing 737823
- Aircraft serial: 31158
- Aircraft time: 40,328 hours, 17,531 cycles
- System (JASC): [3440 · Independent Position Determining System](https://openairdocs.org/jasc/3440)
- Part: Deu
- Part number: 4081600940
- Condition: Inoperative
- Location: Zone 200
- Stage of operation: CL
- How discovered: V
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA202607305439

## Discrepancy

AIRCRAFT WAS GROUNDED: FIRST OFFICERS PFD LOST AIRSPEED AND ALTITUDE MOMENTARILY SEVERAL TIMES FOLLOWED BY DISPLAY SOURCE 2 WARNING LIGHT. BOTH ENGINES PLACED INTO ALTERNATE MODE PER QRH. LOST FIRST OFFICERS FLIGHT DIRECTOR ON FINAL. MAINTENANCE REPLACED DEU #2 IAW AMM 31-62-21.

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