Date: 201908
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Light: Daylight
Aircraft: Large Transport
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Takeoff / Launch
ATC / advisory: Tower ZZZ
Aircraft component: Engine
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; First Officer
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Second reporter function: Captain; Pilot Flying
Anomaly: Aircraft Equipment Problem Less Severe
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Rejected Takeoff; Flight Crew Returned To Gate; General Maintenance Action
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: We were cleared for takeoff on Runway X from ZZZ Tower. After aligning the aircraft with the runway centerline; the Captain pushed the throttles to approximately 40% N1 for stabilization check. After; he moved the throttles forward to the takeoff setting and pressed the TO/GA button. Almost immediately the left engine went to approximately 90% N1 and the right remained at approximately 40% N1. The resulting asymmetric thrust forced the aircraft to the right. The Captain confirmed the reject and brought the throttles to idle while controlling the aircraft with rudder and tiller. I contacted ZZZ Tower regarding the reject and asked for the fire trucks due to the unknown condition. We reached an approximate speed of approximately 15 knots and was able to exit at Taxiway E where we waited for the Fire Chief to release us. The Captain opted to have the aircraft towed to the gate. We terminated at the gate uneventfully. Recommend continuing highlighting asymmetric thrust on initial takeoff at the Training Center. This entire event was very sudden and quick in duration.


Second narrative: We were cleared for takeoff on Runway X from Tower. After aligning the aircraft with the runway center line; I pushed the throttles up to approximately 40% N1; and the engines advanced symmetrically. I pressed the TO/GA (Take-off/Go-around) button and followed the throttles up to take off power setting. I noted that the right engine seemed to be lagging the left engine as I looked outside to crosscheck runway alignment. As the thrust came up; the aircraft began pushing to the right. I crosschecked the engine settings; the left engine was at takeoff power; the right engine still at approximately 40%.I simultaneously pulled the throttles to idle and input full left rudder; announcing the reject. When this proved to be ineffective; I transitioned to nose wheel steering and input left nose wheel steering to the stop. Nose wheel steering was ineffective as we continued to push to the right edge of the runway. Once the left engine decelerated enough for the nose wheel steering to become effective again; the aircraft lurched to the left. I corrected with nose wheel steering and aimed for Taxiway E. We taxied clear of the runway; set the parking brake; announced to the passengers to remain seated; and [requested priority handling from ATC and] Crash Fire and Rescue. By this time there was a very strong; unidentified acrid odor. As we waited for the trucks; I further announced to the passengers that fire trucks would be responding purely as a precaution. We had the response vehicles confirm there wasn't any smoke from the brakes or any visible damage to the nose gear. I elected to have the aircraft towed to the gate. Upon post flight walkaround; the right nose wheel tire's shoulder was visibly damaged; scrubbed. I concluded this was the source of the acrid smell; the tire being dragged across the pavement at 78 degrees opposite lock. Max speed was approximately 15 knots. More methodical engine run-up. I recommend this scenario for simulator training. I have over 15 years [of] experience on this aircraft and I was shocked when I had zero control with nose wheel steering until the thrust differential was reduced.


Synopsis: Air carrier flight crew reported executing a rejected takeoff due to asymmetrical engine power produced when setting takeoff power.