Commercial Fixed Wing
Flight Crew Last 90 Days 200; Flight Crew Total 7200; Flight Crew Type 594
Aircraft Equipment Problem Critical; Inflight Event / Encounter Loss Of Aircraft Control
Flight Crew Returned To Gate; Flight Crew Regained Aircraft Control; Flight Crew Rejected Takeoff; General Declared Emergency; General Maintenance Action
Aircraft
We were cleared for takeoff and the Captain set the power and accelerated normally. I made the 100 KT call and then the aircraft yawed to the left and then snapped back towards the centerline. It then did this once more and the Captain initiated an abort. I made the call to Tower that we were aborting. We slowed the aircraft and then taxied off the runway.I made the 'Remain Seated' call to the passengers and Tower asked if we could turn onto the Delta Taxiway. We did; but we did not set the parking brake. I requested CFR be sent to check for any indication of a fire and then ran the QRH with the Captain during which we noted the brakes were in the Cooling Zone of the brake cooling chart. I spoke with the Flight Attendants and the Captain made an announcement to the passengers. Once we determined there was no fire and that we could return safely to the gate; I called Maintenance; Operations; and the ramp while the Captain talked to Ground and taxied to the gate. Before coming to a stop; we made sure the ground crew knew not to chalk the mains; only the nose wheel. Once at a stop; we shut down the engines. Emergency Services came up and said that the brakes reached 650 degrees. We spoke to the flight attendants on the ground who said they felt the yaw and that the rear flight attendants were thrown side to side in their jump seats. There were no injuries reported.
[Narrative 2 contained no additional information.]
Uncommanded deviations in the yaw axis during late stages of the takeoff roll resulted in a rejected takeoff performed by the flight crew of an unidentified air carrier aircraft.