CORP ACFT HAS NMAC WITH TAXIING ACFT WHEN CLRED FOR TKOF.

Narrative

THE RWY INCURSION INCIDENT HAPPENED ON RWY 34R. WX WAS CLR; VISIBILITY WAS 40 MI. I WAS THE PIC AND ALSO THE PF AT THE TIME. AS WE TAXIED TOWARD THE S END OF RWY 34R; WE OBSERVED 3 SMALL SINGLE ENG ACFT RUNNING UP WITH SEVERAL LARGE ACFT ON APCH. WE RPTED TO THE TWR THAT WE WERE READY FOR TKOF. TWR TOLD US TO HOLD SHORT. WE READ BACK THE HOLD SHORT INSTRUCTION. ABOUT 20 SECONDS LATER; THE TWR CLRED US FOR TKOF. AS I WAS BRINGING UP THE PWR; MY CO-CAPT NOTICED AN SMT RAPIDLY TAXIING TOWARD 34R AT THE MID FIELD POINT FROM W TO E. MY CO-CAPT REMARKED THAT HE HOPED THE ACFT WAS GOING TO STOP. AT THAT POINT; THERE WAS STILL SEVERAL HUNDRED YARDS BTWN THE TAXIING ACFT AND THE HOLD SHORT LINE WHICH I FELT WAS PLENTY ADEQUATE FOR HIM TO STOP. WE CONTINUED WITH THE TKOF ROLL. THE AIR TEMP WAS COOL AND WE WERE LIGHT SO OUR ACFT WAS ACCELERATING VERY RAPIDLY. WHEN WE WERE AT APPROX 80 KTS; I DEFINITELY KNEW THE OTHER ACFT WASN'T STOPPING. AT THAT POINT I DECIDED THAT WE COULD GET OFF AND OVER HIM WHERE STOPPING WOULD BE MARGINAL. WE CONTINUED THE TKOF ROLL. THE SMT HAD JUST CLRED THE RWY AS WE FLEW BY AT 50 FT AGL. APCH CTL REQUESTED US TO CALL THEM AT OUR DEST. THE TWR OPERATOR THOUGHT HE HAD CLRED US INTO POS AND HOLD. A PLAY BACK OF THE TWR TAPE SHOWED HE HAD CLRED US FOR TKOF.