SMT MADE TKOF WHILE REPORTER IN LTT WAS BACK TRACKING ON THE SAME RWY.

Narrative

WE WERE DEPARTING FROM ROCKSOUND ARPT IN THE BAHAMAS WITH 3 PAX FOR A FLT BACK TO TETERBORO; NJ. AFTER BOARDING OUR PAX AND STARTING ENGS WE ADVISED ROCKSOUND UNICOM THAT WE WERE TAXIING OUT FOR DEP. BACK TAXIING ON THE ACTIVE RWY WOULD BE REQUIRED; UNICOM ADVISED US THAT SMT HAD JUST DEPARTED THE RAMP AREA; TAXIING FOR THE DEP RWY; AND THAT THERE WAS AN ACFT 10 MI N; INBND. WE ADVISED THAT WE HAD THE SMT IN SIGHT PERHAPS 2000' IN FRONT OF US AND CONTINUED TAXIING FOR OUR DEP BEHIND THE SMT. AS WE TAXIED OUT ONTO THE RWY; WE ADVISED UNICOM THAT WE WERE BACKTAXIING ON THE ACTIVE FOR DEP. (WE FOLLOWED THE SMT FOR SEVERAL THOUSAND FT.) WHILE WE WERE STILL ABOUT 1500' FROM THE END OF THE RWY; WE SAW THE SMT LINE UP IN POS WITH HIS LIGHTS ON AND START HIS TKOF ROLL. HE NEVER STATED HIS INTENTION TO DO SO ON UNICOM. WE IMMEDIATELY MOVED AS FAR TO THE RIGHT SIDE OF THE RWY AS WE COULD. THE SMT LIFTED OFF AT A POINT ABEAM OUR POS WITH MAYBE 20-30' WINGTIP CLRNC. NEEDLESS TO SAY; THE SMT HAD OUR UNDIVIDED ATTN. WE HAVE BEEN OPERATING OUT OF THIS ARPT FOR MORE THAN 7 YRS NOW AND HAVE MANY TIMES SHARED THE RWY WITH ANOTHER ACFT WHILE BACKTAXIING FOR TKOF. THIS; HOWEVER; IS THE FIRST TIME I HAVE EVER HAD ANYONE TKOF WHILE WE WERE STILL IN FRONT OF THEM.