FLC OF AN SMT TWIN TOOK OFF WITHOUT CLRNC AFTER BEING CLRED INTO POS ONLY.

Narrative

THE COPLT READ THE ACFT CHKLIST AND ALSO HANDLED ALL ATC COMS. WE TAXIED FOR DEP ON RWY 18; AND COMPLETED THE BEFORE TKOF PORTION OF THE CHKLIST WHILE HOLDING SHORT OF THE RWY; AT WHICH TIME THE COPLT RPTED TO THE TWR THAT WE WERE 'READY FOR TKOF.' WHILE THIS WAS HAPPENING I BRIEFED THE PAX FOR TKOF. WHEN I HAD FINISHED; THE COPLT TOLD ME 'WE'RE CLRED TO GO.' WE TAXIED ONTO THE RWY; HE READ THE LINEUP PORTION OF THE CHKLIST; AND I ACKNOWLEDGED HIS CALL OUTS. AT THE END OF THE CHKLIST I ASKED 'ALL SET?' HE REPLIED 'WE'RE READY;' AND WE COMMENCED THE TKOF ROLL AND DEPARTED THE ARPT. AT APPROX 200 FT AGL; THE TWR CTLR SAID 'SMT WHERE ARE YOU GOING?' AND I REALIZED THAT ALL WAS NOT AS IT SHOULD BE. WE HAD NOT RECEIVED TKOF CLRNC; BUT CLRNC TO 'TAXI INTO POS AND HOLD;' AS WAS DETERMINED BY FURTHER COM WITH THE TWR CTLR. THE FLT CONTINUED IN AN OTHERWISE NORMAL FASHION; WE WERE 'HANDED OFF' TO CGX DEP CTL; WHO GAVE US A REVISED HDG AND ALT; AND WE FLEW ON TO OUR DEST; MKG. THIS IS ANOTHER EXAMPLE OF MISSED OR IMPROPER COMS BETWEEN CREW MEMBERS. SINCE I DID NOT ACTUALLY HEAR THE CLRNC THAT WE WERE GIVEN; BEING INVOLVED WITH BRIEFING THE PAX; I SHOULD HAVE VERIFIED THAT WE HAD ACTUALLY RECEIVED THAT CLRNC; INSTEAD OF HAVING ASSUMED THAT WE HAD; BASED UPON THE COPLT SAYING THAT WE 'CLRED TO GO;' WHEN HE ACTUALLY MEANT; 'GO ONTO THE RWY.' ALSO; WHEN HE AGREED WITH MY QUESTION; 'WE ALL SET?' IT CONFIRMED TO ME THAT WE WERE CLRED FOR TKOF. AFTER THE FLT HAD ENDED AND WE WERE RECONSTRUCTING THE CHAIN OF EVENTS THAT CONTRIBUTED TO THIS INCIDENT; WE DID COME TO SOME CONCLUSIONS. THE FIRST WAS THAT AT NO TIME WAS THE FLT IN ANY DANGER; THE WX BEING VFR AND THERE BEING NO OTHER TFC IN THE AREA. ALSO; WE BOTH AGREED THAT; SINCE WE HAD NOT FLOWN WITH EACH OTHER BEFORE; WE SHOULD HAVE BEEN EXTRA VIGILANT; ESPECIALLY IN THE AREAS OF COM AND COORD OF COCKPIT DUTIES. PERSONALLY; I BELIEVE THAT WE LEARN INVALUABLE LESSONS FROM MISTAKES SUCH AS THESE; AND I KNOW THAT BECAUSE OF THIS INCIDENT; I WILL NEVER LINE UP FOR TKOF ON A RWY WITHOUT RECALLING WHAT HAPPENED ON THIS DAY; AND KNOWING POSITIVELY THAT I HAVE TKOF CLRNC BEFORE I ADVANCE THOSE THROTTLES.