Narrative:

Approximately 25 minutes into the flight at FL220; we experienced an uncommanded flap deployment of approximately three to four degrees at 280 KIAS. At the time we were accelerating per ATC from 250 KIAS (econ cruise) to an assigned speed of 320 KIAS. The gear and flap indications appeared on the EICAS 1 after being extinguished the entire time and the green flap indication moved from zero to approximately half way to eight degrees before returning to zero degrees. The red speed tape appeared on both pfd 1 and 2 at that time due to the aircraft believing that the flaps were deployed and we were at 280 KIAS; but no overspeed clacker. The aircraft seemed stable at the time of the first occurrence. The QRH was consulted and searched for any type of checklist for an uncommanded flap deployment but none was found. During the QRH search; a 'flaps degraded' status message appeared on EICAS 2 and this was looked up in the QRH. The system then returned to normal; with the gear and flap indicators extinguished and the aircraft behaving normally. We chose not to accelerate anymore and remaining at the speed of initial occurrence; which was 280 KIAS. ATC was advised of a possible issue and we were turned off the arrival. An emergency was not yet declared. This happened again approximately five minutes later after the gear and flap indicators had extinguished. The second time; the aircraft 'ballooned' by approximately 80 ft of altitude gain with the 'seat feeling' of the flaps deploying. Again; this was only about three to four degrees. No roll was experienced which led us to believe the flaps were deploying evenly. The indications were only momentarily and a diversion was considered. The aircraft returned to a normal state. The indications of the flaps and gear appeared twice more with the speed tape again showing red on both pfds; but no indication of actual flap deployment. An emergency was declared and runway 9L was requested due to the possibility of an uncommanded it is understood that the QRH cannot possibly contain every possible situation imaginable and that this is not a 'normal' occurrence. The thought of diverting was considered numerous times; as the first occurrence happened while over flying a system airport. However; the decision to continue to our filed destination was made due to the extended runway lengths available as well as the amount of emergency equipment should the problem get worse. The aircraft was in a flyable state or else a diversion would have been made.

Related reports:

Google
 

Original NASA ASRS Text

Title: A CRJ-200's trailing edges flaps had an uncommanded extension to about three to four degrees several times at cruise altitude so the airspeed was limited; an emergency declared and the flight continued to the filed destination because of long runways.

Narrative: Approximately 25 minutes into the flight at FL220; we experienced an uncommanded flap deployment of approximately three to four degrees at 280 KIAS. At the time we were accelerating per ATC from 250 KIAS (Econ Cruise) to an assigned speed of 320 KIAS. The gear and flap indications appeared on the EICAS 1 after being extinguished the entire time and the Green Flap indication moved from zero to approximately half way to eight degrees before returning to zero degrees. The red speed tape appeared on both PFD 1 and 2 at that time due to the aircraft believing that the flaps were deployed and we were at 280 KIAS; but no overspeed clacker. The aircraft seemed stable at the time of the first occurrence. The QRH was consulted and searched for any type of checklist for an uncommanded flap deployment but none was found. During the QRH search; a 'Flaps Degraded' status message appeared on EICAS 2 and this was looked up in the QRH. The system then returned to normal; with the gear and flap indicators extinguished and the aircraft behaving normally. We chose not to accelerate anymore and remaining at the speed of initial occurrence; which was 280 KIAS. ATC was advised of a possible issue and we were turned off the arrival. An emergency was not yet declared. This happened again approximately five minutes later after the gear and flap indicators had extinguished. The second time; the aircraft 'ballooned' by approximately 80 FT of altitude gain with the 'seat feeling' of the flaps deploying. Again; this was only about three to four degrees. No roll was experienced which led us to believe the flaps were deploying evenly. The indications were only momentarily and a diversion was considered. The aircraft returned to a normal state. The indications of the flaps and gear appeared twice more with the speed tape again showing red on both PFDs; but no indication of actual flap deployment. An emergency was declared and Runway 9L was requested due to the possibility of an uncommanded It is understood that the QRH cannot possibly contain every possible situation imaginable and that this is not a 'normal' occurrence. The thought of diverting was considered numerous times; as the first occurrence happened while over flying a system airport. However; the decision to continue to our filed destination was made due to the extended runway lengths available as well as the amount of emergency equipment should the problem get worse. The aircraft was in a flyable state or else a diversion would have been made.

Data retrieved from NASA's ASRS site as of July 2013 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.