C172 pilot and safety pilot reported the trim system was sticky inflight. After landing the system m...

Attributes
ACN	1617564
Time
Date	201902
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	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	Final Approach
Route In Use	Direct
Flight Plan	None
Component
Aircraft Component	Elevator Trim System
Person 1
Function	Pilot Flying Single Pilot
Qualification	Flight Crew Private
Experience	Flight Crew Last 90 Days 12 Flight Crew Total 83 Flight Crew Type 81
Person 2
Function	Pilot Not Flying Single Pilot
Qualification	Flight Crew Private
Experience	Flight Crew Last 90 Days 35 Flight Crew Total 205 Flight Crew Type 12
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural Published Material / Policy

Narrative:

I first noticed a trim stickiness when beginning descent into ZZZ1. To play it safe; I did not manipulate the trim until we had landed (as it was in an okay position on approach). Once on the ground and shutdown; the trim was taken through two cycles and appeared to be properly functional again. We departed to return to ZZZ. In the climb; approximately 10NM northwest ZZZ1; the trim appeared to get stuck again. Slight back-pressure was required to maintain the desired rate of climb. Once at cruise; the trim was adjusted slightly down to maintain level flight. The decision to continue to the aircraft's base was made due to the lack of issue in cruise; availability of maintenance at the base; and need to land eventually regardless.on approach to ZZZ; it became apparent the trim was still sticky. I opted to use a longer downwind in order to allow for more time to prepare for the approach. Once on final approach; moderate back-pressure was required to maintain a desired airspeed/pitch. The landing was relatively uneventful; however significantly more back-pressure than usual was required throughout the approach and rollout.once on the ground; we attempted to cycle the trim and heard an audible sound when it got stuck. We had a CFI from the flight school come check the trim issue and confirm that the trim was getting stuck. The plane was subsequently grounded for maintenance. No damage or injury occurred during this incident.

Original NASA ASRS Text

Title: C172 pilot and safety pilot reported the trim system was sticky inflight. After landing the system made an audible sound and became stuck.

Narrative: I first noticed a trim stickiness when beginning descent into ZZZ1. To play it safe; I did not manipulate the trim until we had landed (as it was in an okay position on approach). Once on the ground and shutdown; the trim was taken through two cycles and appeared to be properly functional again. We departed to return to ZZZ. In the climb; approximately 10NM NW ZZZ1; the trim appeared to get stuck again. Slight back-pressure was required to maintain the desired rate of climb. Once at cruise; the trim was adjusted slightly down to maintain level flight. The decision to continue to the aircraft's base was made due to the lack of issue in cruise; availability of maintenance at the base; and need to land eventually regardless.On approach to ZZZ; it became apparent the trim was still sticky. I opted to use a longer downwind in order to allow for more time to prepare for the approach. Once on final approach; moderate back-pressure was required to maintain a desired airspeed/pitch. The landing was relatively uneventful; however significantly more back-pressure than usual was required throughout the approach and rollout.Once on the ground; we attempted to cycle the trim and heard an audible sound when it got stuck. We had a CFI from the flight school come check the trim issue and confirm that the trim was getting stuck. The plane was subsequently grounded for maintenance. No damage or injury occurred during this 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.