Date: 202107
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: Regional Jet 200 ER/LR (CRJ200)
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Takeoff / Launch
Airspace: Class B ZZZ
ATC / advisory: Tower ZZZ
Aircraft component: Throttle/Power Lever
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; First Officer
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Second reporter function: Pilot Flying; Captain
Anomaly: Aircraft Equipment Problem Critical
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Diverted; Flight Crew Landed in Emergency Condition; Flight Crew Inflight Shutdown; Flight Crew Returned To Departure Airport; Flight Crew Overcame Equipment Problem
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: When departing Runway XXR in ZZZ; the left throttle was difficult to set for takeoff power; but by the time the problem was identified the aircraft was already at V1. Departure commenced and climb continued. The left engine APR (Automatic Performance Reserve) fired and the left engine was non-responsive to the movement of the throttle. When reaching 10;000 ft the aircraft was under control; the Captain transferred the controls to me and told me to get delayed vectors. The Captain started the QRH checklist for Uncommanded acceleration/ENG OVERSPEED after completion of the emergency checklist. The single engine in-flight engine shutdown checklist was commenced on Abnormal. After completing Abnormal the problem still continued. The Captain [advised] ATC and commenced the Severe Engine Damage In-flight QRH procedure. After selecting LH ENG FIRE PUSH switch light; the problem resolved and all associated emergency; abnormal; and normal checklists were completed. The captain and I briefed the approach and landing to Runway XXR at ZZZ. The Flight Attendant was notified that the aircraft would be returning to ZZZ for a precautionary landing. The passenger announcement was made in flight advising passengers of a maintenance issue that required the aircraft to return to landing at ZZZ. The Captain had me transfer the controls back to him and landed the aircraft. Upon landing we taxied off Runway XXR and [airport] crews did a post flight walk around of the aircraft. During crew walk around another passenger announcement was made advising passengers to remain seated with seat belts fastened and that the aircraft would be parking at [the] gate. After the aircraft was given all clear; the aircraft taxied to the gate and parked without further issue. After gate arrival passenger announcement was made advising passengers of the reason we returned to field. After parking at the gate; Maintenance write up was made by the Captain and associated phone calls were made to document the incident. [A] defective thrust lever on the left engine [could be solved by] possible checks more often on engine thrust levers.


Second narrative: When departing Runway XXR in ZZZ; the left throttle was difficult to set for takeoff power as reported by the First Officer; but by the time the problem was identified the aircraft was already at V1. Departure commenced and climb ensued. Left Engine APR (Automatic Performance Reserve) fired and Left Engine was non-responsive to throttle lever movement. Upon reaching 10;000 ft and aircraft under control. Captain transferred controls to the First Officer and told FO to get delay vectors. Captain started QRH checklist for Uncommanded Acceleration/ENG OVERSPEED after completion of emergency checklist. Commenced Single Engine Inflight Engine Shutdown checklist on Abnormal. After completing Abnormal problem was still ongoing. Captain then [advised] ATC and commenced Severe Engine Damage in Flight QRH procedure. Upon selecting LH ENG FIRE PUSH switch light problem resolved and all associated emergency; abnormal; and normal checklists were completed. Flight crew briefed approach and landing to Runway XXR at ZZZ. Flight attendant was notified that we would be returning to ZZZ for a precautionary landing. Passenger announcement was made in flight advising passengers of a maintenance issue that required return to landing at ZZZ. Captain then commenced transfer of controls back to Captain and landed aircraft. Upon landing aircraft taxied off Runway XXR and [airport] crews did a post flight walk around of the aircraft. During crew walk around another passenger announcement was made advising passengers to remain seated with seat belt fastened and that aircraft would be parking at [the] gate. After aircraft was given all clear we taxied to the gate and parked without further issue. After gate arrival passenger announcement was made advising passengers of reason we needed to return to field. After parking at gate maintenance write-up was made and associated phone calls were made to document incident.


Synopsis: Flight crew reported experiencing a malfunction with one of the aircraft's power levers resulting in a return to the departure airport.