A Q400 first officer reported uncommanded rudder trim full left. He and the captain ran the procedur...

Attributes
ACN	861507
Time
Date	200911
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Dash 8-400
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Component
Aircraft Component	Rudder Trim System
Person 1
Function	First Officer Pilot Flying
Qualification	Flight Crew Commercial Flight Crew Flight Instructor Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 90 Flight Crew Type 900
Events
Anomaly	Aircraft Equipment Problem Less Severe

Narrative:

On climb out the captain and I noticed that the airplane began a gradual left turn. I immediately disconnected the auto pilot and noticed that the airplane required a lot of right rudder. Aircraft control was always positive. The captain and I began to trouble shoot the problem and discovered that the rudder trim had full uncommanded trim to the left. Captain immediately pulled out the QRH and ran the procedure for uncommanded rudder trim. Procedure called for us to retrim the rudder as close to neutral and then pull the associated circuit breaker. After running the procedure rudder pressure was normal. We discussed what had happened and sent a message to operations via ACARS to inform them of the anomaly. Operations sent a us a message that maintenance would take a look at it when we arrived at our destination; and to push the tcs button. We proceeded to do as requested. After landing maintenance came on board and proceeded to run through their checks of the systems.

Original NASA ASRS Text

Title: A Q400 First Officer reported uncommanded rudder trim full left. He and the Captain ran the procedure; coordinated with maintenance; and continued the flight to destination.

Narrative: On climb out the Captain and I noticed that the airplane began a gradual left turn. I immediately disconnected the auto pilot and noticed that the airplane required a lot of right rudder. Aircraft control was always positive. The Captain and I began to trouble shoot the problem and discovered that the rudder trim had full uncommanded trim to the left. Captain immediately pulled out the QRH and ran the procedure for uncommanded rudder trim. Procedure called for us to retrim the rudder as close to neutral and then pull the associated circuit breaker. After running the procedure rudder pressure was normal. We discussed what had happened and sent a message to Operations via ACARS to inform them of the anomaly. Operations sent a us a message that maintenance would take a look at it when we arrived at our destination; and to push the TCS button. We proceeded to do as requested. After landing Maintenance came on board and proceeded to run through their checks of the systems.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

A Q400 first officer reported uncommanded rudder trim full left. He and the captain ran the procedure; coordinated with maintenance; and continued the flight to destination.