# SDR UALA2009101403233

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 14, 2009
- Submitted: October 14, 2009
- Operation: Air carrier
- Aircraft: N116UA
- Make and model: Boeing 747422
- Aircraft serial: 26908
- Aircraft time: 44,565 hours, 5,264 cycles
- Engine: Pwa PW4056
- System (JASC): [2215 · Autopilot Main Servo](https://openairdocs.org/jasc/2215)
- Part: Servo
- Part number: A717206
- Part serial: 1480
- Condition: Faulty
- Location: Autopilot Sys
- Stage of operation: AP
- How discovered: O
- Nature of condition: E, F
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UALA2009101403233

## Discrepancy

YOKE SHOOK VIOLENTLY W- AUTOPILOT ENGAGED DURING FINAL APPROACH WITH FLAPS 20 +GEAR UP.  ALL WIRING CHECKS OKAY.  REPLACED CENTER FLIGHT CONTROL COMPUTER AS A PRECAUTION.  REPLACED CENTER ELEVATOR AUTOPILOT SERVO.  ACCMP'D CHECK OF AUTOPILOT SYSTEM.  ALL AFDS TESTS.  CHECKED OK AND RETURNED TO CAT 3 STATUS.

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