A B777 CAPT QUESTIONS; AFTER THE FACT; HIS DECISION TO ABORT A TKOF IN WHAT MIGHT BE PERCEIVED AS NON COMPLIANCE WITH COMPANY POLICY REGARDING HIGH SPD ABORTS.

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FLT X WAS SCHEDULED SVC FROM NRT WITH A B777-200 ACFT. IT IS A DOUBLE AUGMENTED FLT WITH 1 CAPT AND 3 TYPE RATED FO'S. THE 'FLYING' FO WAS THE DESIGNATED PLT FOR THIS LEG. THE FLT DEPARTED NRT ON TIME AT XA19 IN NRT. THE ACTIVE RWY AT NRT WAS RWY 16R WHICH IS OVER 13000 FT LONG. THERE WAS A 3 KT HEADWIND AND THE RWY SURFACE WAS DRY. TKOF COMMENCED AT XA35. THE INITIAL PORTION OF THE TKOF ROLL WAS NORMAL. AT 115-120 KTS; THE MASTER WARNING SYS ACTIVATED WITH A 'CONFIGN GEAR STEERING EICAS' MESSAGE. AFTER A 2-3 SECOND DELAY; THE CAPT ASSUMED CTL OF THE ACFT AND BEGAN REJECTED TKOF PROCS. THE SPD AT INITIATION OF REJECTION WAS 125-130 KTS. COMPUTED V1 WAS 171 KTS. THE CAPT DEACTIVATED THE AUTOBRAKES REJECTED TKOF FEATURE WITH FOOT PRESSURE AND SLOWED THE ACFT USING MINIMAL BRAKING AND REVERSE THRUST OVER THE REMAINING 7000 FT OF RWY. THE ACFT WAS TAXIED CLR OF THE RWY AND STOPPED ON THE PARALLEL TXWY. THE BRAKES WERE LEFT OFF. THE CREW CONSULTED THE FLT MANUAL FOR BRAKE COOLING CONSIDERATIONS AND PROCS. LCL OPS WERE NOTIFIED OF THE SIT. MECHS CAME OUT TO THE ACFT TO MAKE AN INITIAL DETERMINATION OF POTENTIAL DAMAGE TO THE LNDG GEAR AND BRAKES. NO DAMAGE WAS OBSERVED. THE CREW CONTACTED ACR DISPATCH AND MAINT FOR DISCUSSION OF THE SIT. AFTER A SUITABLE DELAY TO ALLOW BRAKE COOLING; THE ACFT WAS TAXIED TO THE TERMINAL FOR FURTHER INSPECTION OF THE TIRES; LNDG GEAR AND BRAKES. IT WAS DETERMINED THAT THERE WAS NO DAMAGE TO THE ACFT AS A RESULT OF THE REJECTED TKOF. IT WAS ALSO DETERMINED THAT THERE WAS NO STRUCTURAL FAILURE OF THE MAIN GEAR STEERING UNIT. THE MAIN GEAR STEERING WAS DEACTIVATED AND PLANS WERE MADE TO REDISPATCH THE ACFT AND CREW. AT XC18 THE FLT DEPARTED THE GATE. A NORMAL TKOF AND FLT BEGAN AT XC40. THE SUBSEQUENT FLT WAS NORMAL. PROCS ARE IN PLACE TO PREVENT UNNECESSARY ABORTS AT HIGH SPDS. I MAKE A POINT OF BRIEFING THE DECISION POINTS BTWN LOW SPD AND HIGH SPD ABORTS ON EVERY FLT. THIS SPD NORMALLY COINCIDES WITH THE '80 KTS THRUST SET' CALL. I BRIEF THAT BEFORE THIS POINT WE ARE IN A 'STOP' MODE TO A DEGREE; BUT ONCE THE 80 KTS CALL IS MADE; WE ARE DEFINITELY IN THE 'GO' MODE UNLESS THE ACFT IS DEEMED UNSAFE TO FLY. WHEN I REFLECT ON MY DECISION TO ABORT AT A SPD HIGHER THAN 80 KTS; I RECALL SEVERAL THOUGHTS GOING THROUGH MY MIND IN THE 2-3 SECONDS BEFORE THE TKOF WAS REJECTED. THESE WERE: 1) IN MY MIND; WE HAD BARELY GONE PAST THE 80 KTS CALL AND WHEN I BEGAN THE REJECTION PROC; I TRULY BELIEVED THE SPD WAS NO MORE THAN 100-110 KTS; LEAVING SUFFICIENT RWY TO STOP WITHOUT USING MAX ENERGY BRAKING. BOTH NON FLYING FO'S REMEMBER SEEING THE SPD IN THE 125-130 KT RANGE; SO OUR SPD WAS HIGHER THAN I THOUGHT. THE RESULTING STOPPING MANEUVER DID NOT REQUIRE UNUSUAL BRAKING FORCES. IN FACT; I WAS THINKING THAT WE MIGHT NOT HAVE HEATED THE BRAKES TO THE POINT OF REQUIRING A DELAY. THE BRAKES DID; HOWEVER; HEAT UP TO THE POINT THAT A DELAY OF SLIGHTLY OVER 1 HR WAS REQUIRED TO ALLOW COOLING. 2) IT OCCURRED TO ME THAT IF WE BECAME AIRBORNE AND HAD A SERIOUS MAIN LNDG GEAR PROB; WE WOULD HAVE TO DEAL WITH A HIGH SPD LNDG. I WOULD RATHER DEAL WITH IT ON THE GND; GIVEN WHAT I FELT WAS A RELATIVELY LOW SPD. 3) THE CONFIGN GEAR STEERING WARNING IS VERY LOUD AND REPETITIVE. IT CANNOT BE SILENCED. IT IS; BY DESIGN; MEANT TO GRAB THE CREW'S ATTN. I FOUND THE WARNING SO LOUD AND DISTRACTING THAT IT MAY HAVE BEEN A FACTOR IN MAKING MY DECISION TO ABORT. IT WOULD NOT DEACTIVATE UNTIL V1. IT IS A VERY COMPELLING WARNING. PLTS ARE CONDITIONED TO STOP WHEN THEY HEAR IT SINCE IT NORMALLY OCCURS WHEN TKOF THRUST IS SET. I HAD THIS WARNING ONCE BEFORE AT A SPD OF 50 KTS AND REJECTED THAT TKOF ALSO. I FIND MYSELF THINKING THAT WARNINGS LIKE THIS SHOULD BE INHIBITED EARLIER IN THE TKOF ROLL SO THEY WILL NOT OCCUR AT SPDS AT WHICH ABORTING IS NOT APPROPRIATE. 4) AFTER THE FACT; I REALIZED VERY QUICKLY THAT ALL MY REASONING DID NOT PUT ME ON THE RIGHT SIDE OF ACR POLICY. I SHOULD HAVE CONTINUED THE TKOF. I WAS VERY SURPRISED IN THAT I THOUGHT ALL MY REASONING WAS CORRECT AT THE MOMENT OF DECISION. IT IS VERY DIFFICULT FOR ANYONE TO REALLY STAY ON TOP OF THE SIT GIVEN THE NATURE OF OUR WDB INTL FLYING. THAT IS; VERY FEW LEGS AND FLYING MOST OF OUR TKOFS IF FAR AWAY TIME ZONES. I HAVE PROVEN TO MYSELF THAT PRACTICE IN SIMULATORS AND BRIEFING PROCS WILL NOT ALWAYS OVERCOME HUMAN INSTINCTS.