# SDR 2006UALA02427

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 23, 2006
- Submitted: January 2, 2007
- Operation: Air carrier
- Aircraft: N520UA
- Make and model: Boeing 757222
- Aircraft serial: 24890
- Aircraft time: 53,988 hours, 20,257 cycles
- Engine: Pwa PW2037
- System (JASC): [2740 · Stabilizer Control System](https://openairdocs.org/jasc/2740)
- Part: Trim System
- Condition: Malfunctioned
- Location: Stabilizer
- Stage of operation: CL
- How discovered: O
- Nature of condition: F
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2006UALA02427

## Discrepancy

UNCOMMANDED STAB TRIM DURING CLIMBOUT.  NOSE DOWN TRIM WAS FELT.  SAM HAD NO FAULT BALLS LATCHED.  DETERMINED THE PROBLEM TO LEFT SAM.  REPLACED LEFT SAM STABILIZER-TRIM /AILERON LOCKOUT UNIT.

---
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.