Regional Jet 200 ER/LR (CRJ200)
Flight Crew Air Transport Pilot (ATP)
Time Pressure; Training / Qualification; Troubleshooting; Workload
Aircraft Equipment Problem Critical; Inflight Event / Encounter Loss Of Aircraft Control
Flight Crew FLC complied w / Automation / Advisory; Flight Crew Regained Aircraft Control; Flight Crew Took Evasive Action
Aircraft
This event occurred while descending approaching 15;000 feet MSL. We were told by the Center Controller to contact Approach Control. Approach cleared us to descend to 5;000 feet MSL. At about 13;000 feet MSL and descending at approximately 2;000 feet per minute; I slowly and smoothly; extended the flight spoilers to full extension in order to slow from 300 knots to 250 knots. There was light to moderate rain and possible convective activity in the area; and at this time we were in instrument meteorological conditions with smooth air. About 40-45 seconds later the plane violently rolled to the right. I quickly grabbed the control wheel; disconnected the autopilot; and turned the control wheel fully to the left; putting in full aileron deflection. This reaction stopped the roll to the right from continuing any further; but did not return us to level flight. Approximately 3 seconds later I pushed the flight spoiler lever full in. This immediately corrected the problem and we returned to level flight in approximately 8 more seconds. The whole event happened quickly in a matter of seconds; but we believed the maximum bank was between 45-50 degrees to the right. At this time the First Officer noticed a L FLT SPLR caution message and stated so. I instructed him to run the Quick Reference Checklist for L FLT SPLR. He completed the checklist and we agreed that both flight spoilers were now down at zero extension; the plane was flying normally and had an amber box outlining the left flight spoiler on the Flight Controls EICAS page. I then instructed him to call our Flight Attendant and see if she was injured or if any passengers were requiring assistance. The First Officer returned and stated that she said she was fine and was not standing; nor were any passengers. We continued with normal operations and elected to land on the longest runway. Upon landing all spoilers deployed expect for the left flight spoiler which required me to again add full aileron deflection to the left in order to keep the wings level. As airspeed was decreased I was able to relax the aileron deflection and taxi us off the active runway. We continued to have the L FLT SPLR caution message all the way until I shutoff the hydraulics on the shutdown checklist.
A CRJ-200 rolled violently 40-45 degrees right and the L FLT SPLR EICAS alerted after the flight spoilers were fully extended during descent. Full left aileron started a partial recovery with wings level after spoiler retraction.