# SDR DXTA2026010906452

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 5, 2026
- Submitted: January 9, 2026
- Operation: Air carrier
- Aircraft: [N907QS](https://openairdocs.org/aircraft/N907QS), registered now
- Make and model: Cessna 680A
- Registry model: [Cessna 680A](https://openairdocs.org/model/cessna-680a) (OpenAirDocs)
- Aircraft serial: 680A0321
- Aircraft time: 3,759 hours, 2,517 cycles
- System (JASC): [3440 · Independent Position Determining System](https://openairdocs.org/jasc/3440)
- Part: Ahrs
- Part number: 1451303000
- Part serial: 11157
- Condition: Faulted
- Stage of operation: CR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DXTA2026010906452

## Discrepancy

DURING CRUISE FLIGHT AMBER HEADING MIS COMPARE DISPLAYED.  WE NOTED A 8 DEGREE DIFFERENCE BETWEEN HDG1 AND HDG2.  HDG2 MATCHED THE STBY SO WE REVERTED HDG1 OVER TO HGD2.  AFTER LANDING THE HDG MIS COMPARE CLEARED AND ALL INDICATIONS ARE NORMAL.  THIS IS THE SECOND OCCURRENCE. CORRECTIVE ACTION: REMOVED NR 1 AHRU DUE TO HDG MISMATCH. INSTALLED REPAIRED AHRU P/N 145130-3000 S/N 8256 IN THE #1 POSITION. REPAIR ACCOMPLISHED BY NORTHROP GRUMMAN, CERTIFICATE: DE.145.0114, WORK ORDER: 175808, DATE:12-22-25. ALL WORK COMPLETED IN REFERENCE WITH CITATION 680A MAINTENANCE MANUAL CHAPTER 34-20-10. COMPLIED WITH RFTS# 116058 REV.0. TECHS ADDED ONE WASHER BEHIND BOTH SCREWS ON AHRU #1 J1 AND J6 CONNECTOR, VERIFIED SECURE.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.