Narrative:

On final after we were fully configured for the approach; we noticed that the N1 on the left engine remained at about 82% with the thrust levers at idle. After a brief discussion about the issue; we initiated a missed approach up to 4000 ft. The captain informed the tower of the missed approach and the high thrust setting on the left engine and I continued to fly the aircraft. At altitude; I continued flying the aircraft and took over the radios as the captain began looking for a QRH procedure that best fit our situation. On the leveloff with both thrust levers at idle; we were unable to maintain 250 KTS; and I informed ATC of our 280 KT airspeed. After deciding that the best course of action for the high thrust setting was to perform the single engine QRH procedure; we opted to call maintenance first. At this time; I declared an emergency; let ATC know that we would be shutting down the left engine; and that we would need additional vectors to run the checklists. The captain talked to the flight attendant; let the passenger know what was going on; and then talked to maintenance. We then ran the single engine QRH with the addition of pushing the 'engine fire push' switch because moving the left thrust lever to shutoff had no effect on the N1 setting. When the QRH and all the other checklists had been performed; I continued to fly the aircraft back for a single engine landing at ZZZ.

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Original NASA ASRS Text

Title: CRJ200 FLT CREW REPORTS THRUST STUCK AT 82% N1 ON LEFT ENGINE DURING APPROACH. AFTER MISSED APPROACH; EMERGENCY IS DECLARED; ENGINE IS SHUT DOWN; AND SINGLE ENGINE LANDING ENSUES.

Narrative: ON FINAL AFTER WE WERE FULLY CONFIGURED FOR THE APCH; WE NOTICED THAT THE N1 ON THE L ENG REMAINED AT ABOUT 82% WITH THE THRUST LEVERS AT IDLE. AFTER A BRIEF DISCUSSION ABOUT THE ISSUE; WE INITIATED A MISSED APCH UP TO 4000 FT. THE CAPT INFORMED THE TWR OF THE MISSED APCH AND THE HIGH THRUST SETTING ON THE L ENG AND I CONTINUED TO FLY THE ACFT. AT ALT; I CONTINUED FLYING THE ACFT AND TOOK OVER THE RADIOS AS THE CAPT BEGAN LOOKING FOR A QRH PROC THAT BEST FIT OUR SITUATION. ON THE LEVELOFF WITH BOTH THRUST LEVERS AT IDLE; WE WERE UNABLE TO MAINTAIN 250 KTS; AND I INFORMED ATC OF OUR 280 KT AIRSPD. AFTER DECIDING THAT THE BEST COURSE OF ACTION FOR THE HIGH THRUST SETTING WAS TO PERFORM THE SINGLE ENG QRH PROC; WE OPTED TO CALL MAINT FIRST. AT THIS TIME; I DECLARED AN EMER; LET ATC KNOW THAT WE WOULD BE SHUTTING DOWN THE L ENG; AND THAT WE WOULD NEED ADDITIONAL VECTORS TO RUN THE CHKLISTS. THE CAPT TALKED TO THE FLT ATTENDANT; LET THE PAX KNOW WHAT WAS GOING ON; AND THEN TALKED TO MAINT. WE THEN RAN THE SINGLE ENG QRH WITH THE ADDITION OF PUSHING THE 'ENG FIRE PUSH' SWITCH BECAUSE MOVING THE L THRUST LEVER TO SHUTOFF HAD NO EFFECT ON THE N1 SETTING. WHEN THE QRH AND ALL THE OTHER CHKLISTS HAD BEEN PERFORMED; I CONTINUED TO FLY THE ACFT BACK FOR A SINGLE ENG LNDG AT ZZZ.

Data retrieved from NASA's ASRS site as of May 2009 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.