Date: 201703
Local time of day: 0601-1200
Location: ZZZZ.Airport, FO
Light: Daylight
Aircraft: Regional Jet 200 ER/LR (CRJ200)
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
ATC / advisory: Center ZZZZ
Aircraft component: Aileron Trim System
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Overcame Equipment Problem; General Maintenance Action
Contributing factors: Aircraft; Human Factors
Primary problem: Human Factors

Narrative: While in cruise we observed what appeared to be anomalous indications of an out of trim condition with the autopilot engaged. While executing normal turns enroute; we occasionally observed both 'AP TRIM IS LWD' (when turning left) and 'AP TRIM IS RWD' (when turning right) caution messages; with the corresponding 'Boxed-A' icon on the PFD. After several instances of this; I decided to disconnect the autopilot; in an effort to determine whether the indications were the result of a malfunctioning autopilot/trim system; or something else. While hand-flying; I noted the pressure required to actuate the ailerons was much greater than normal; though roll authority was well within an acceptable margin. The QRH was completed for the above-mentioned caution messages; and Dispatch and Maintenance Control were notified of our experience; and of our intent to continue to ZZZZ. Approximately 10 minutes prior to landing I noted that the aileron control pressure rapidly returned to normal; to 'break free'; as I described in the discrepancy. The terminal descent; approach; and landing was without anomaly; and Maintenance Control was notified upon arrival at the gate.Upon a detailed inspection by local contract mechanics in ZZZZ; it was found that the increased aileron control pressure was likely due to the main landing gear bay 'pan' (ZZZZ mechanic's term; not mine) rubbing against the aileron and aileron trim control cables. This was due to the fact that (according to the ZZZZ mechanic's description) the MLG bay 'pan' was not properly secured by mechanics during the previous inspection.Whereas I cannot speak to the specific maintenance procedures and protocol under which the MLG bay 'pan' would be removed or unsecured; this event gives credence to the need to ensure that all panels - even those not readily observable - are secured by mechanics prior to signing-off inspections. In fact; the condition was undetectable during the pilots' preflight inspection and flight control checks (all appeared normal); only becoming manifest in high-speed cruise flight; when the local airflow apparently 'pushed' the panel up and against the control cables.It is my hope that this circumstance brings awareness to both mechanics and pilots alike; to strive to maximize situation awareness and to avoid complacency. In this case; a mechanic's inattention to detail offered the potential for unintended consequences.




Synopsis: CRJ-200 Captain reported that with the autopilot engaged the aileron appeared to be out of trim. With the autopilot disengaged the ailerons were extremely heavy.