CE560XLS first officer reported encountering a likely frozen pitch trim anomaly on descent. Pitch tr...

Narrative:

While level at 40;000 feet we are given a descent to FL340. The captain chose vertical speed on the flight director and shortly thereafter we received a pitch trim malfunction. The captain disconnected the autopilot attempted to trim the airplane; then put the autopilot back on and shortly thereafter received another pitch trim malfunction. Then realized that the pitch trim was possibly frozen. We took out the corresponding checklist to run the jammed pitch trim item checklist. We continued descending as we continued to proceed with the 'jammed' checklist. At about 24;000 feet we realized that it was actually frozen and decided to continue. We stated the nature of our problem ATC was very helpful and we received vectors to our destination because we were within a hundred miles. The weather was marginal VFR (1000 overcast; 10 miles visibility). As we descended to 4000 feet preparing for our approach the outside air temperature had warmed to 16 degrees C. After a couple minutes at 4000 feet the pitch trim unfroze; and the trim appeared to be 100% functional. We continued and landed without any incident.

Original NASA ASRS Text

Title: CE560XLS First Officer reported encountering a likely frozen pitch trim anomaly on descent. Pitch trim returned to normal operation when they descended to warmer temperatures.

Narrative: While level at 40;000 feet we are given a descent to FL340. The Captain chose vertical speed on the flight director and shortly thereafter we received a pitch trim malfunction. The Captain disconnected the autopilot attempted to trim the airplane; then put the autopilot back on and shortly thereafter received another pitch trim malfunction. Then realized that the pitch trim was possibly frozen. We took out the corresponding checklist to run the JAMMED PITCH TRIM item checklist. We continued descending as we continued to proceed with the 'Jammed' checklist. At about 24;000 feet we realized that it was actually frozen and decided to continue. We stated the nature of our problem ATC was very helpful and we received vectors to our destination because we were within a hundred miles. The weather was marginal VFR (1000 overcast; 10 miles visibility). As we descended to 4000 feet preparing for our approach the outside air temperature had warmed to 16 degrees C. After a couple minutes at 4000 feet the pitch trim unfroze; and the trim appeared to be 100% functional. We continued and landed without any incident.

Data retrieved from NASA's ASRS site 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	1262859
Time
Date	201505
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Citation V/Ultra/Encore (C560)
Operating Under FAR Part	Part 91
Flight Phase	Descent
Flight Plan	IFR
Component
Aircraft Component	Elevator Trim System
Person 1
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Less Severe Inflight Event / Encounter Other / Unknown

CE560XLS first officer reported encountering a likely frozen pitch trim anomaly on descent. Pitch trim returned to normal operation when they descended to warmer temperatures.