# SDR AALA202503177691

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 14, 2025
- Submitted: March 17, 2025
- Operation: Air carrier
- Aircraft: [N903NN](https://openairdocs.org/aircraft/N903NN), registered now
- Make and model: Boeing 737823
- Aircraft serial: 31153
- Aircraft time: 36,282 hours, 15,556 cycles
- System (JASC): [3421 · Attitude Gyro and Indicating System](https://openairdocs.org/jasc/3421)
- Part: Adiru
- Part number: HG2050AC11
- Part serial: 00022859
- Condition: Unreliable
- Location: Zone 100
- Part time: 11,402 hours, 52,250 cycles
- Stage of operation: NR
- How discovered: V
- Nature of condition: S, J, G
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA202503177691

## Discrepancy

AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED DUE TO: AIRSPEED UNRELIABLE ON CLIMB OUT. AIRCRAFT AIR INTERRUPTED BACK TO AND LANDED SAFELY AT STL.  REMOVED AND REPLACED RIGHT HAND (ADIRU)-AIR DATA INERTIA REFERENCE UNIT. PER AMM 34-21-01.

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