# SDR ASAA2012091192866

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 1, 2012
- Submitted: September 13, 2012
- Operation: Air carrier
- Aircraft: [N558AS](https://openairdocs.org/aircraft/N558AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35177
- Aircraft time: 23,665 hours, 7,034 cycles
- Engine: Cfmint CFM567B27
- System (JASC): [2220 · Speed-Attitude Correction System](https://openairdocs.org/jasc/2220)
- Part: Yaw Damper
- Part number: 285A10107
- Part serial: 285A1010D04386
- Condition: Failed
- Location: Ee Bay
- Part time: 23,682 hours, 7,042 cycles
- Stage of operation: AP
- How discovered: O
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2012091192866

## Discrepancy

YAW DAMPER DISENGAGED TWICE ON APPROACH. (APPROX 1500 & 300AGL) ACFT GROUNDED. NR 1 SMYD SHOWS YD SERVO LOOP FAULT WITH MX MESSAGE 22-21006.  ACCOMPLISHED FIM 22-23-809.  TEST PASS & NO FAULTS UNDER EXISTING FAULTS. ON NEXT FLIGHT, ON TAKE-OFF, Y/D KICKED-OFF.  QRH FOLLOWED. Y/D REMAINED ON REMAINDER OF FLIGHT.  REACCOMPLISHED SWEEP TEST WITH NO FAULTS NOTED.  REF FIM 22-23, TASK 809,  PRECAUTIONARY REPLACED NR 1 SMYD REF MM 27-32-42. OPS NORMAL.

---
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.