CAPT OF WDB ORDERED TKOF ABORT DUE TO A NON READING AIRSPD INDICATOR.

Narrative

ON TKOF ROLL; CAPT'S AIRSPD NEEDLE VIBRATED AROUND 60 KTS AS IS EXPECTED. ABOUT THE TIME ONE WOULD EXPECT AIRSPD ALIVE I LOOKED OVER AT THE FO'S AIRSPD INDICATOR AND NOTICED IT WAS ACCELERATING RAPIDLY TOWARD 100 KTS. I LOOKED BACK AT MY AIRSPD INDICATOR AND NOTICING IT WAS STILL NOT MOVING I REJECTED TKOF. THE FO THINKS WE REACHED A SPD OF 120 KTS. THIS WAS FO'S LEG; BUT I HAD CTL OF THROTTLES. AUTO BRAKES WERE IN USE. PEAK TEMP WAS 295 DEGS. MAINT LATER INDICATED IT WAS A TOTAL FAILURE OF #1 ADC. THE ABORT WAS UNEVENTFUL AND THE CREW PERFORMED ACCORDING TO TRAINING. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT THIS INCIDENT OCCURRED AT IAH; TX; ARPT. THE CAUSE OF THE FAULTY AIRSPD INDICATOR WAS A BAD ADC ELECTRICAL DRIVE. THIS SAME PART FAILED ON A PREVIOUS FLT AND THE REPLACEMENT PART FAILED AGAIN DURING THIS TKOF ABORT. THIS PART CONTINUED TO WORK OK ON FUTURE FLTS. RPTR FURTHER STATED THAT HE BELIEVED THAT AN ABORT WAS BETTER THAN CONTINUING SINCE THERE WAS PLENTY OF RWY TO STOP AND A LARGE AMOUNT OF FUEL WOULD HAVE NEEDED TO BE DUMPED IF RETURN LAND BECAME NECESSARY.