Date: 201708
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: EMB ERJ 170/175 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Climb
Airspace: Class B ZZZ
ATC / advisory: TRACON ZZZ
Aircraft component: Aileron Control System
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Confusion; Distraction; Troubleshooting; Workload
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Aircraft Equipment Problem Dissipated; Flight Crew Became Reoriented; Flight Crew Took Evasive Action; Flight Crew Requested ATC Assistance / Clarification; General Maintenance Action
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: Aircraft demonstrated no anomalies during preflight and taxi duties. The flight control check was accomplished prior to taxi and was seen as normal. There was a very long wait for takeoff. We were cleared to takeoff; and had been assigned to climb via the departure; stopping at 9000 ft. Takeoff roll and initial climb out appeared normal. We were following previously departing traffic and I actuated the controls as normal to keep the airplane climbing on course. Nothing felt unusual. During the turn; I started thinking that the ailerons were feeling strange. There was an unusual resistance to movement and the controls would not center on their own. If I induced a roll; I had to physically move the ailerons back to center or they would stick in place and keep us rolling. I wasn't sure if I was imagining things or not. I requested the autopilot turned on and mentioned to the FO that something felt strange with the ailerons. I turned off the autopilot and did some slight banking turns to verify the issue was still present. It was. I had the FO take over flying to verify his side was acting the same. He verified he had the same issue. I took control again. By this point we were nearing RVSM so I had the autopilot reengaged since it seemed to be doing fine. We looked at the QRH procedure for Jammed Control Wheel (ROLL). The condition says: Higher than normal control forces. I was very skeptical of doing this procedure because the airplane was not demonstrating any inability to control itself. It just felt strange to us. I initiated ACARS messages with dispatch; indicating the problem we had. I do not have the exact messages written down; but we were asked about the hydraulic systems status. Both the hydraulics and flight control screens showed perfectly normal indications. We did end up tuning to ARINC to improve communication. At that point; I turned over the airplane and COMM 1 to the FO. On ARINC; we discussed weather and current fuel status; as well as potential options for deviating. I indicated that I was not sure that pulling the aileron disconnect handle would improve our situation; and could in fact make the situation more dangerous than it was.I decided that we would request a descent out of RVSM to further test the controls. We told center we would like FL290 with deviations to work out a potential problem. We descended to FL290 and I slowed the plane to 260 KIAS to hopefully help me determine the degree of control limitation; if any. After switching control back and forth between myself and the FO; we both agreed that something was up; but that it did not necessarily appear to be a safety concern at that time. We were off ARINC during this phase. We decided to climb back to FL350 with the autopilot. The FO and I agreed that while things were not normal; disconnecting the control wheels seemed like a bad idea. The airplane was operating on autopilot with no indications of problems. The procedure would result in losing the autopilot; one aileron; multi-function spoilers; and costing us RVSM capability. That would have resulted in a definite diversion.I called dispatch again on ARINC; with the FO operating COMM 1 and flying. I said I would feel more comfortable talking to a chief pilot. We discussed what the airplane was doing; what we had tried so far; and what the plan was from there. With input from the chief pilot; it was decided that we would start hand flying early on the descent to determine the airplane's capabilities. We were destined for an airport with a short runway. If; at any point; the airplane felt like it was not controlling adequately; we would initiate a diversion and likely proceed with the QRH disconnect procedure. I reminded him that this could result in a very last minute diversion. After talking on ARINC; I coordinated with my dispatcher on fuel status. I requested that we officially add the divert airport as an alternate to verify I had enough fuel to fly the approach at our filed destination and at that point; abort and divert if needed. I had no intention of attempting a landing at our destinations short runway if the ailerons were not giving us adequate roll control. I briefed the FO to stay in the mindset of flying in case we have to disconnect the controls and it ended up that he was flying the approach and landing.At 18;000 ft and 280 KIAS the descent check was complete; and I disconnected the autopilot. I immediately noticed that the controls felt normal again. We were flying the arrival; which gave us plenty of time to determine the status of our flight controls. I did a number of small rolls left and right and verified that the controls now felt normal and were springing back to center on their own. I told the FO that everything seemed normal and that we shall continue as planned. We landed with flaps full with no issues. Once we were clear of the runway; I verified we had full control movement and everything still felt normal. This was also verified on the flight control synoptic page. We arrived at the gate without further incident. We both went out and inspected the airplane. I looked closely at the flight controls and inspected the cabling in the wheel wells. I also checked the hydraulic access panels. Nothing out of the ordinary was found. I talked to dispatch and they informed me that they had already started repositioning an airplane to arrive shortly. We discussed whether I felt comfortable flying this plane again or if I wanted to take the spare that was already enroute. I said that since they already had a spare enroute and that this was potentially a serious problem; I didn't want to take it without a proper inspection from Maintenance.




Synopsis: EMB-175 Captain reported a stiff aileron condition which developed during climb and continued until the descent to lower altitudes. After landing the aileron movement felt normal.