# SDR P5CA2021122600434

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 26, 2021
- Submitted: December 27, 2021
- Operation: Air carrier
- Aircraft: [N852GT](https://openairdocs.org/aircraft/N852GT), registered now
- Make and model: Boeing 747-87UF
- Registry model: [Boeing 747-87UF](https://openairdocs.org/model/boeing-747-87uf) (OpenAirDocs)
- Aircraft serial: 37571
- Aircraft time: 41,577 hours, 6,168 cycles
- System (JASC): [2721 · Rudder Tab Control System](https://openairdocs.org/jasc/2721)
- Part: Actuator
- Part number: 6013K000101
- Part serial: 12013769
- Condition: Faulted
- Location: Rudder
- Part time: 41,577 hours, 6,168 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/P5CA2021122600434

## Discrepancy

"RUDDER RATIO SNGL" EICAS MESSAGE.  PERFORMED WIRING CHECK OF WIRING BETWEEN RUDDER RATIO ACTUATOR AND YSM PER IFIM TASK 27-21-00-810-844 AND WDM 27-21-31. NO FAULTS NOTED. RUDDER RATIO ACTUATOR REPLACED IAW B747 AMM 27-21-12/401, OPS CHECK GOOD.  RUDDER RATIO L & R GROUND TEST GOOD IAW B747 AMM 27-21-00-720-810.

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