NMAC IN UNAUTH UNCOORD RWY ENTRY OP TKOF AT NON TWR ARPT. TKOF ON OCCUPIED RWY.

Narrative

WHILE HOLDING FOR TKOF FROM RWY 28; 1 JET AND 1 LIGHT ACFT LANDED. THERE WAS CONVERSATION ON THE FREQ ABOUT HAVING TO BACK TAXI; ALTHOUGH I WAS SOMEWHAT CONFUSED ABOUT THE SIT; NOT COMPREHENDING THAT WITH THE CLOSING OF RWY 22; THE NORMAL METHOD OF RETURNING TO THE TERMINAL WAS NOT AVAILABLE AND THAT LNDG ACFT WOULD HAVE TO BACK TAXI TO THE TERMINAL. WHEN I HAD ARRIVED; A DIFFERENT RWY HAD BEEN IN USE. IN ADDITION; THERE WERE CONVERSATIONS ON THE UNICOM FREQ ABOUT SEVERAL ARPTS; AND THERE WAS SOME DOUBT IN MY MIND ABOUT WHERE THE PLANES AND GND CALLS WERE LOCATED. (MANY OF THE CALLS WERE SUCH AS '...WHAT DO YOU WANT US TO DO?') AFTER A SECOND JET LANDED; I TOOK RWY 28 AND ANNOUNCED THAT I WAS IN POS ON RWY 28. A RADIO CALL ASKED 'IS THE SMA PLANNING TO HOLD OR WHAT?' THINKING THAT THE CALL WAS FROM A PLANE IN THE PATTERN; OR WAITING BEHIND ME TO TKOF; I REPLIED 'SMA X WILL BE HOLDING UNTIL JET CLRS THE RWY.' AT THAT POINT; THE JET WAS STILL ROLLING OUT. AT ABOUT THE TIME I GAVE THE RADIO CALL; I SAW THE JET TURN TO THE R; AND APPEARED TO BE CLRING THE RWY (THE JET WAS PROBABLY 3000-3500 FT DOWN THE RWY). ON THIS ASSUMPTION; I BEGAN MY TKOF ROLL. THERE WAS A LOT OF TFC AT THE ARPT AT THE TIME AND IT APPEARED THE RWY WAS CLR. AS I BEGAN THE ROLL; AND HAD GOTTEN TO APPROX 45 KTS; I REALIZED THAT THE JET HAD DONE A 180 DEG TURN AND WAS ROLLING TOWARDS ME. SINCE THE JET WAS OVER 1500 FT AHEAD AND I WAS ALREADY AT CLOSE TO FLYING SPD; I DECIDED THAT IT WOULD BE SAFER TO CONTINUE MY ROLL RATHER THAN HOPING I COULD STOP IN TIME. I KNEW THAT I COULD EASILY CLR THE JET ONCE AIRBORNE; AND COULD ALSO TURN TO ONE SIDE. THERE ARE SEVERAL LESSONS TO BE LEARNED FROM THIS INCIDENT. FIRST; IT IS UNFORTUNATE THAT MORE FREQS AREN'T MADE AVAILABLE FOR UNICOM. BY HAVING SO MANY CONVERSATIONS AT DIFFERENT ARPTS; CONFUSION IS LIKELY. SECOND; BY FAILING TO USE FULL RADIO LANGUAGE (I.E.; 'EAST HAMPTON TFC; JET Y XXXX BACK TAXIING RWY 28 EAST HAMPTON'); IT WAS NOT ENTIRELY CLR WHO WAS DOING WHAT. THIRD; AND MOST IMPORTANT; IS THAT THERE SHOULD BE NO REASON TO BEGIN A TKOF ROLL UNTIL YOU ARE CERTAIN THAT THE RWY IS CLR. IN THIS SIT; IT WAS NOT ENOUGH TO ASSUME THAT WHEN THE JET TURNED R THAT HE WAS CLRING THE RWY. RATHER; I SHOULD HAVE WAITED UNTIL HE DECLARED HE WAS CLR. IF THERE WAS ANY DOUBT; I SHOULD HAVE QUESTIONED THE JET. I SHOULD NOT HAVE BEEN PRESSURED BY THE CALL ASKING MY INTENTIONS.