# SDR CALA2026043015898

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 28, 2026
- Submitted: April 30, 2026
- Operation: Air carrier
- Aircraft: [N12754](https://openairdocs.org/aircraft/N12754), registered now
- Make and model: Boeing 737724
- Aircraft serial: 30464
- Aircraft time: 71,166 hours, 27,739 cycles
- System (JASC): [3421 · Attitude Gyro and Indicating System](https://openairdocs.org/jasc/3421)
- Part: Adiru
- Part number: HG2050AC07
- Part serial: 338
- Condition: Faulted
- Location: Nr 1
- Part time: 20,821 hours, 8,980 cycles
- Stage of operation: CR
- How discovered: V
- Nature of condition: J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026043015898

## Discrepancy

HEADING FAIL ON CAPT SIDE ADIRU 1 REPORTED HEADING FAULT, TCAS REPORTED HEADING FAULT, DEU REPORTED SEVERAL ADIRU 1 FAULTS. DUE TO MULTIPLE FAILURES LINKED TO ADIRU 1 REMOVED AND REPLACED ADIRU 1. REF AMM 34-21-01. ADIRU OPS CHECK GOOD. TCAS OPS CHECK GOOD. REF AMM 34-45-02-700-801-C2. PERFORMED LAND VERIFY TEST REF AMM 22-11-00, CAT STATUS RESTORED TO FULL CAPABILITY.

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