PL2 PLT HAD A TRACK DEV IN SFB CLASS D AND CONFLICT DEPARTING TFC.

Narrative

I WAS ON PRACTICE ILS APCH TO RWY 27R AT SFB UNDER CLR SKY AND GOOD VISIBILITY. ORL APCH ISSUED A MISSED APCH TO CLB RWY HDG 2000 FT; AND RETURN TO THE APCH FREQ. SHORTLY AFTER; I WAS INSTRUCTED TO CONTACT TWR. SFB TWR INSTRUCTED A JET TO 'POS AND HOLD' ON RWY 27R; AND INSTRUCTED ME TO EXECUTE A MISSED APCH 1 MI FROM THE THRESHOLD WITH A 'RIGHT 360.' SINCE THE TERMINOLOGY WAS '360' VICE '3-6-0;' THE TERM 'HDG' WAS NOT USED; AND NO ALT WAS STATED; I INTERPED THE INSTRUCTION TO BE A R 360 FOR SPACING BEHIND THE DEPARTING JET. I COMPLIED AT 1 MI; RPTED THE MISSED; AND COMMENCED A CLBING R TURN. ONLY AFTER THE HDOF BACK TO DEP DID I DETERMINE THAT SFB TWR HAD ACTUALLY ISSUED AN AMENDED MISSED APCH INSTRUCTION. BY THIS TIME; I WAS MORE THAN 90 DEGS R OF ATC'S INTENDED HDG OF 3-6-0; AND STILL TURNING R. MY ACFT CONFLICT WITH OTHER ACFT WAS CAUSED BY SFB TWR'S FAILURE TO ADHERE TO PROPER AIM SECTION 4-2-10 TERMINOLOGY OF DISCRETE NUMBERS FOR HDG INSTRUCTIONS. FOR THIS PARTICULAR HDG; THE SLANG '360' IS EQUIVALENT TO THE COMMON TERM FOR A NORMAL SPACING MANEUVER OFTEN ISSUED BY TWR TO ACFT IN THE TFC PATTERN. SPEAKING THE DISCRETE CHARACTERS '3-6-0' OR USING THE WORD 'HDG' IN THE INSTRUCTION WOULD HAVE REMOVED ALL DOUBT AND COULD HAVE AVERTED A POTENTIAL TFC CONFLICT.