# SDR FDEA202001030010

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 3, 2020
- Submitted: January 3, 2020
- Operation: Air carrier
- Aircraft: [N609FE](https://openairdocs.org/aircraft/N609FE), registered now
- Make and model: Doug MD-11F
- Registry model: [Doug MD-11F](https://openairdocs.org/model/mcdonnell-douglas-md-11f) (OpenAirDocs)
- Aircraft serial: 48549
- Aircraft time: 84,604 hours, 20,340 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Actuator
- Part number: 1536400503
- Part serial: 0280
- Condition: Malfunctioned
- Location: Left
- Stage of operation: LD
- How discovered: O
- Nature of condition: F
- Precautionary procedure: L
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/FDEA202001030010

## Discrepancy

DURING APPROACH TO KMEM, WITH AUTOPILOT ENGAGED AND AIRCRAFT FULLY CONFIGURED, AIRPLANE BEGAN A SIGNIFICANT RHYTHMIC PULSING WITH CORRESPONDING YOKE MOVEMENT. WENT AROUND TO TROUBLESHOOT & PULSING STOPPED. FULLY CONFIGURED EARLY WITH NO PULSING. PASSING 1200' ON SECOND APPCH SHORTLY AFTER DUAL LAND ENGAGED, PULSING BEGAN AGAIN. CLICKED OFF  AUTOPILOT & PULSING STOPPED. PULSING LASTED APPROX 30 SEC BEFORE INITIAL GO AROUND & ONLY 1 SEC BEFORE WE DISCONNECTED A/P ON 2ND APPCH. EMERGENCY DECLARED AFTER 1ST GO AROUND. R&R OF IB LT ACTUATOR.

---
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.