Regional Jet 200 ER/LR (CRJ200)
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 108
Aircraft Equipment Problem Less Severe; Deviation - Altitude Excursion From Assigned Altitude
Flight Crew Landed As Precaution; Flight Crew Returned To Departure Airport; Flight Crew Overcame Equipment Problem; General Maintenance Action
Aircraft
Enroute to ZZZ1 at 12;000 and 300 kts with AP on; I saw the flap indicator appear on ED1 and momentarily display flaps extended before returning to zero. Approx 1-2 seconds later; the aircraft pitched nose down slightly and descended about 200 feet before leveling off and returning to our assigned altitude. We notified Dispatch and Maintenance; and decided that the best course of action would be an air return to ZZZ. We flew back to ZZZ and landed without further incident.Cause - The FO and I initially both suspected a momentary uncommanded flap movement due to the indication and the pitch down moment we experienced. We discussed the situation with Operations and they requested we return to ZZZ; a decision that we agreed with. Later discussions with Maintenance brought up the possibility that an erroneous sensor indication may have caused the auto trim system to trim the aircraft nose down.
CRJ-200 Captain reported a flap indication issue followed by an uncommanded pitch down movement.  The crew contacted Dispatch and Maintenance Control and decided to return to the departure airport.