Date: 201309
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: Thunderstorm; Windshear
Light: Daylight
Aircraft: B737-700
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Takeoff / Launch
ATC / advisory: Tower ZZZ
Aircraft component: Nosewheel Steering
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Not Flying
Human factors: Situational Awareness
Anomaly: Aircraft Equipment Problem Critical; Ground Event / Encounter Loss Of Aircraft Control
Detector: Person Flight Crew
When detected: In-flight
Result: Aircraft Equipment Problem Dissipated; Flight Crew Rejected Takeoff; Flight Crew Returned To Gate; General Maintenance Action
Contributing factors: Aircraft; Weather
Primary problem: Aircraft

Narrative: Weather in local area; specifically thunderstorms and heavy gusty winds out of SSW.  Set up MAX Power Takeoff for Precautionary Profile due to W/S Advisory in ATIS.  Long line of aircraft for runway.  Shut down Number 1 Engine while waiting for departure corridor to open.  Restarted Number 1 when flights started moving again.  Number 1 had been stabilized for 10 minutes before taxi into lineup and wait.  Captain appeared to do good job centering aircraft nose on runway centerline.  Given takeoff clearance; Captain ran engines up to 40%; depressed TOGA; engines growled and nose immediately yawed to the right.  Captain appeared to counter with tiller.  Encountered major 'chattering' as nose continued to veer off; and then Captain immediately pulled throttles to idle while nose started to come back to the left and once again parallel Runway centerline.  We stopped parallel to Runway centerline; offset by about 10-12' and what seemed to be 50-75' down the runway.  We agreed our takeoff attempt was over and elected to exit the runway at closest intersection.  Whole event lasted just a few seconds; probably never got faster than 10 knots.  Another carrier Airbus at hold short said over Tower frequency that smoke came from nose wheel during the event.  We taxied off runway; faced west and held our position for a few minutes while we assessed the situation.  We agreed to taxi back to gate slowly and have Maintenance take a look.  Coordinated with Operations to effect plan; and Captain assessed nose wheel steering on the way back; fully prepared to stop immediately if need be.  Aircraft was pulled from service.  After talking with Company Safety the next day; they believed it to be a nose wheel steering hydraulic metering valve issue; which caused the nose wheel to remain cocked out of commanded position. Check the engines/EEC's to make sure it was not an engine issue.  Then have the nose wheel steering hydraulic cylinder from the event aircraft evaluated.  It was such an out-of-the-norm event following textbook execution of normal procedures that there isn't anything I can think of to prevent it.




Synopsis: A B737-700 nose wheel steering metering valve apparently malfunctioned as takeoff thrust was set which caused the aircraft to veer off centerline and resulted in a low speed rejected takeoff.