What was found
DURING TAKEOFF, BOTH ENGINES AT 60 PERCENT, TOGA SWITCH WAS ACTIVATED & ENGS ACCELERATED NORMALLY, WITHIN SECONDS F/O STATED HE COULD NOT CONTROL A/C & NEEDED FULL RT RUDDER TO KEEP THE A/C STRAIGHT, NWS TILLER WAS CENTERED, REJECTED TAKEOFF AT 90 KTS. ON RETURN TO GATE BRAKES APPEARED NORMAL, NO DRAGGING OR PULLING NOTED, ALL OTHER SYSTEMS APPEARED NORMAL (RTO, HYDS, YAW DAMPER, & ELECTRICAL) & NO WARNING INDICATIONS OF ANY KIND. UPON ARRIVAL AT GATE MX FOUND NR 1 BRAKE EXTREMELY HOT COMPARED TO OTHER BRAKES. R & R NR 1 BRAKE ASSEMBLY, OPS & LEAK CHECKS GOOD. AS PRECAUTION PERFORMED RUDDER POWER CONTROL UNIT TEST & TAXI CHECK, BRAKING & STEERING SYS NORMAL. COULD NOT DUPLICATE PROBLEM ON BRAKE ASSY .