FOREIGN CTLR MIXED UP 2 ACFT WITH SIMILAR CALL SIGNS UNTIL THE RPTR QUESTIONED THE CTLR REGARDING THEIR CLRNC; LOCATION AND INTENTIONS.

Narrative

ON DSCNT FOR LNDG AT ST THOMAS; APPROX 40 MI NW OF THE ARPT; WE WERE GIVEN A VECTOR: L TURN TO 090 DEGS; DSND AND MAINTAIN 6000 FT. SHORTLY THEREAFTER; AN ACFT CHKED ON THE FREQ WITH A CALL SIGN/REGISTRATION SIMILAR TO OURS. THE LAST 2 LETTERS OF THE REGISTRATION WERE THE SAME. THE CTLR GAVE THE OTHER ACFT NUMEROUS VECTORS WHILE WE WERE STILL ON OUR ORIGINAL 090 DEG HDG AND 5000 FT. THE NEXT INSTRUCTION WE RECEIVED WAS A DSCNT TO 3000 FT. WE READ THE CLRNC BACK AND COMPLIED. AFTER SOME TIME HAD PASSED (APPROX 5 MINS); OUR POS WAS THEN 20 MI N OF ST THOMAS ON AN EBOUND HDG GOING AWAY FROM THE ARPT. THINKING THAT THE CTLR HAD FORGOTTEN US; I QUERIED HIM STATING OUR POS AND ALT. HE REPLIED ASKING WHAT WE WANTED TO DO. INFORMED HIM THAT WE WERE 20 MI N OF OUR DEST EBOUND AT 3000 FT AND WE INTENDED TO LAND AT ST THOMAS. HE THEN REPLIED THAT OUR CLRNC WAS ONLY TO 5000 FT. I REPLIED THAT WE WERE INSTRUCTED TO DSND TO 3000 FT AND THE ACFT WITH THE SIMILAR REGISTRATION WAS INSTRUCTED TO 5000 FT. THAT WAS ALL THAT WAS SAID. HE TURNED US S AND VECTORED US FOR ST THOMAS. THE CTLR'S WORKLOAD AT THE TIME WAS HIGH. HE SEEMED CONFUSED BY THE 2 ACFT WITH SIMILAR REGISTRATIONS. NO ACFT WERE ANYWHERE NEAR OUR POS AT THE TIME OF THE INCIDENT; NO SAFETY OF FLT ISSUE.