Q400 first officer reports noticing spoiler extension in cruise on the pfcs display. Visual check do...

Narrative:

During cruise I noticed that on the pfcs [primary flight control surface] display the outboard spoilers where indicating about 1/3 deflection (up). I notified the captain and then looked out the right wing and didn't see any part of the right outboard spoiler showing. The captain then looked at the left wing and also saw nothing abnormal. He also noticed that the rudder was showing a deflection to the left even though the trim indicator showed right deflection. There was no caution light illuminated and the aircraft was not handling abnormally; however the autopilot was on. On direction from the captain I contacted the dispatcher controlling our flight through company radio. As I was initially contacting dispatch the pfcs display showed that the outboard spoilers had stowed and the rudder returned to neutral. After a discussion with dispatch and maintenance control we were directed to divert. I contacted ATC and advised them of our intentions to divert as the captain was making a PA to the passengers on the situation. On landing; operations notified us that we where swapping into the spare and also ramp transferring the passengers. We departed with no other issues.

Original NASA ASRS Text

Title: Q400 First Officer reports noticing spoiler extension in cruise on the PFCS display. Visual check does not reveal any anomalies. During discussion with Maintenance; indications return to normal but flight is directed to divert.

Narrative: During cruise I noticed that on the PFCS [Primary Flight Control Surface] display the outboard spoilers where indicating about 1/3 deflection (up). I notified the Captain and then looked out the right wing and didn't see any part of the right outboard spoiler showing. The Captain then looked at the left wing and also saw nothing abnormal. He also noticed that the rudder was showing a deflection to the left even though the trim indicator showed right deflection. There was no caution light illuminated and the aircraft was not handling abnormally; however the autopilot was on. On direction from the Captain I contacted the Dispatcher controlling our flight through Company Radio. As I was initially contacting Dispatch the PFCS display showed that the outboard spoilers had stowed and the rudder returned to neutral. After a discussion with Dispatch and Maintenance Control we were directed to divert. I contacted ATC and advised them of our intentions to divert as the Captain was making a PA to the passengers on the situation. On landing; Operations notified us that we where swapping into the spare and also ramp transferring the passengers. We departed with no other issues.

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.

Attributes
ACN	901523
Time
Date	201007
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Aircraft 1
Make Model Name	Q400
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Aeroplane Flight Control
Person 1
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Commercial
Events
Anomaly	Aircraft Equipment Problem Less Severe

Q400 first officer reports noticing spoiler extension in cruise on the pfcs display. Visual check does not reveal any anomalies. During discussion with maintenance; indications return to normal but flight is directed to divert.