# SDR CALA2026100520099

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 3, 2026
- Submitted: October 5, 2026
- Operation: Air carrier
- Aircraft: [N27421](https://openairdocs.org/aircraft/N27421), registered now
- Make and model: Boeing 737924ER
- Aircraft serial: 37094
- Aircraft time: 57,232 hours, 20,469 cycles
- Engine: Cfmint CFM567B27
- System (JASC): [3420 · Attitude and Direction Data System](https://openairdocs.org/jasc/3420)
- Part: Adiru
- Part number: HG2050AC07
- Part serial: 01024725
- Condition: Faulty
- Location: Right
- Part time: 72,175 hours, 26,514 cycles
- Stage of operation: CL
- How discovered: O
- Nature of condition: J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026100520099

## Discrepancy

IRS RT FAULT FOLLOWING FIM 34-21 TASK 803, PERFORMED BITE TEST AND FAULT MESSAGES ATTATCHED IN IMAGES. REMOVED AND REPLACED R ADIRU REF. AMM TASK 34-21-01-000-801 AND TASK 34-21-01-400-801. INSTALLATION TEST PASSED.PARTS USED: 60-3421-9-0001,QTY :1 POS - 2 MFG PN ON - HG2050AC11 MFG SN ON - 56025417 M&E SN ON - 05417 M&E PN ON - 60-3421-9-0001 MFG SN OFF - 01024725 MFG PN OFF - HG2050AC07 ROTABLE PARTS CHG:TT # 1136286 SN OFF 4725 PN OFF 29-3421-9-0010 UNIT, ADIRU, AI  OFF 29-3421-9-0010 4725 ON 60-3421-9-0001 5417

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