What was found
DURING TAKEOFF ROLL, THE ACFT DRIFTED STRONGLY TO THE RIGHT ONCE NOSE WHEEL STEERING WAS DEACTIVATED AT APPROX 40KIAS. LEFT RUDDER WAS APPLIED, FOLLOWED QUICKLY WITH LT AILERON WHICH DECREASED, BUT DID NOT STOP DRIFTING TO THE RIGHT. THE TAKEOFF WAS REJECTED AND CONTROL REGAINED USING DIFFERENTIAL BRAKING AND REACTIVATING NOSE WHEEL STEERING. THE ACFT TAXIED BACK TO THE RAMP WITHOUT INCIDENT. OPEN