Narrative:

Climbing out after departing the first officer (first officer) (PF [pilot flying]) called for flaps 8. After selecting flaps 8 we received a single chime and a master caution. Checked the cas and noticed a flaps fail message and that the flaps remained in the 20 degree position. We continued the climb out keeping our focus on flying the aircraft. We received a climb and after reaching roughly 6;000 ft I made sure the first officer had the controls and radios and I took out the flaps fail QRH. At this time ATC had cleared us up to our cruise altitude but we informed them we needed to level at 15;000 for the time being. I ran the QRH and the first officer and I discussed the fuel situation. At 15;000 we were burning roughly 2200 lbs per side with about 5;000 lbs of fuel remaining. At this point we were still 45 min from ZZZ which was IFR and landing north. After calculating our fuel we determined it was not possible to make it to ZZZ with the fuel burn and the weather. The first officer and I agreed at this point we would go ahead and precautionary [notify ATC and request] to give us priority into ZZZ1. I informed dispatch originally of the flaps fail and that we intended to go to ZZZ if possible. Later on they messaged me asking if we were going to ZZZ1 which I acknowledged. I called the flight attendant (flight attendant) normally and let her know the situation and did the test items and that we did not need to brace. I then made a PA to the passengers just letting them know due to the issue we unfortunately don't have enough fuel to make it to ZZZ and that we would be diverting to ZZZ1. After I briefed the approach I took the flight controls from the first officer to perform the flaps 20 landing. Once handed to approach they asked if we wanted the fire trucks standing by and we confirmed as a precautionary measure. We landed and on rollout received a left thrust reverser unlock which ultimately would not stow. Other than that we landed without incident. We cleared the runway; [advised ATC]; and taxied into the gate. We deplaned and the ground crew was very accommodating in helping the passengers. The emphasis on flaps fail in training over my 2.5 years here really helped in knowing what to expect and how to properly handle the situation.

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Original NASA ASRS Text

Title: CRJ-200 Captain reported the flaps would not retract beyond 20 degrees after takeoff.

Narrative: Climbing out after departing the FO (First Officer) (PF [Pilot Flying]) called for flaps 8. After selecting flaps 8 we received a single chime and a master caution. Checked the CAS and noticed a flaps fail message and that the flaps remained in the 20 degree position. We continued the climb out keeping our focus on flying the aircraft. We received a climb and after reaching roughly 6;000 ft I made sure the FO had the controls and radios and I took out the Flaps Fail QRH. At this time ATC had cleared us up to our cruise altitude but we informed them we needed to level at 15;000 for the time being. I ran the QRH and the FO and I discussed the fuel situation. At 15;000 we were burning roughly 2200 lbs per side with about 5;000 lbs of fuel remaining. At this point we were still 45 min from ZZZ which was IFR and landing north. After calculating our fuel we determined it was not possible to make it to ZZZ with the fuel burn and the weather. The FO and I agreed at this point we would go ahead and precautionary [notify ATC and request] to give us priority into ZZZ1. I informed dispatch originally of the flaps fail and that we intended to go to ZZZ if possible. Later on they messaged me asking if we were going to ZZZ1 which I acknowledged. I called the FA (Flight Attendant) normally and let her know the situation and did the TEST items and that we did not need to brace. I then made a PA to the passengers just letting them know due to the issue we unfortunately don't have enough fuel to make it to ZZZ and that we would be diverting to ZZZ1. After I briefed the approach I took the flight controls from the FO to perform the flaps 20 landing. Once handed to approach they asked if we wanted the fire trucks standing by and we confirmed as a precautionary measure. We landed and on rollout received a left thrust reverser unlock which ultimately would not stow. Other than that we landed without incident. We cleared the runway; [advised ATC]; and taxied into the gate. We deplaned and the ground crew was very accommodating in helping the passengers. The emphasis on flaps fail in training over my 2.5 years here really helped in knowing what to expect and how to properly handle the situation.

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.