# SDR CALA2026020213491

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 30, 2026
- Submitted: February 2, 2026
- Operation: Air carrier
- Aircraft: [N23721](https://openairdocs.org/aircraft/N23721), registered now
- Make and model: Boeing 737724
- Aircraft serial: 28940
- Aircraft time: 83,372 hours, 30,832 cycles
- System (JASC): [3425 · Integrated Flight System](https://openairdocs.org/jasc/3425)
- Part: Adiru
- Part number: HG2050AC07
- Part serial: 56001411
- Condition: Faulted
- Location: Zone 100
- Part time: 65,262 hours, 25,804 cycles
- Stage of operation: CL
- How discovered: O
- Nature of condition: F, J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026020213491

## Discrepancy

AFTER TAKE OFF, BOTH CA & FO LOST BOTH HEADING AND LATERAL INDICATIONS,  FO DATA CAME BACK. ACP DCFS BITE,  BPCS, GCU 1 & 2, NO FAULTS.  LT ADIRU HAS ENTER HEADING FAULT ON LAST LEG MAIT MESSAGE 34-21009 FIM 34-21 TASK 808 INITIAL EVALUATION SHOWED NO CURRENT FAULTS IAW ADIRS BITE FIM 34-21 TASK 801. PERFORMED FIM 34-21 TASK 808, WIRING CHECKS OUTLINED BETWEEN THE LT ADIRU & THE MSU CHECKED GOOD. REMOVED AND REPLACED LT ADIRU IAW AMM 34-21-01/401, AS A PRECAUTION.  . ADIRU INSTALLATION TESTS PASSED. FLAGGED FOR CAT LAND TEST.

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