Narrative:

An imminent collision occurred as freeport tower was controling our aircraft and a BE1900 to landing at freeport. Freeport approach cleared us to 1500 ft and cleared us for the VOR runway 24 approach. Shortly after, ATC xferred us to tower. We advised descending through 2500 ft 1500 vr runway 24 approach. At this point, the tower instructions were confusing. They advised to expect to cross over the field and enter a right downwind. I advised we were not visual, but would let them know if we could accept this as we descended to 1500 ft. Shortly after this, my copilot advised traffic CAT 11 O'clock, at which point we saw the BE1900 doing a climbing right turn to avoid us. We both were at 1500 ft. Evidently the BE1900 was on a left downwind to runway 24 and we crossed perpendicular to his flight path. The tower never alerted us to this traffic, and we had not accepted a visual approach. The cloud bases were at 1600 ft, and ragged so we were still operating on the instruments. Better communication between the approach controller and tower, as well as better sequencing and adhering to proper ATC procedures would have prevented the situation. I spoke with the ATC supervisor who admitted the tower controller was a trainee. Better supervision is required. Furthermore, the tower controller evidently thought we were cleared to 2000 ft. The BE1900 pilot asked what altitude we were assigned, at which point the tower controller said 2000 ft. Talking with the ATC supervisor after the event, he said the tower controller was confused and we were cleared to 1500 ft. The marginal WX conditions contributed to the event.

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Original NASA ASRS Text

Title: SA227 CREW AND BE1900 HAD LESS THAN LEGAL SEPARATION AT MYGF.

Narrative: AN IMMINENT COLLISION OCCURRED AS FREEPORT TWR WAS CTLING OUR ACFT AND A BE1900 TO LNDG AT FREEPORT. FREEPORT APCH CLRED US TO 1500 FT AND CLRED US FOR THE VOR RWY 24 APCH. SHORTLY AFTER, ATC XFERRED US TO TWR. WE ADVISED DSNDING THROUGH 2500 FT 1500 VR RWY 24 APCH. AT THIS POINT, THE TWR INSTRUCTIONS WERE CONFUSING. THEY ADVISED TO EXPECT TO CROSS OVER THE FIELD AND ENTER A R DOWNWIND. I ADVISED WE WERE NOT VISUAL, BUT WOULD LET THEM KNOW IF WE COULD ACCEPT THIS AS WE DSNDED TO 1500 FT. SHORTLY AFTER THIS, MY COPLT ADVISED TFC CAT 11 O'CLOCK, AT WHICH POINT WE SAW THE BE1900 DOING A CLBING R TURN TO AVOID US. WE BOTH WERE AT 1500 FT. EVIDENTLY THE BE1900 WAS ON A L DOWNWIND TO RWY 24 AND WE CROSSED PERPENDICULAR TO HIS FLT PATH. THE TWR NEVER ALERTED US TO THIS TFC, AND WE HAD NOT ACCEPTED A VISUAL APCH. THE CLOUD BASES WERE AT 1600 FT, AND RAGGED SO WE WERE STILL OPERATING ON THE INSTS. BETTER COM BTWN THE APCH CTLR AND TWR, AS WELL AS BETTER SEQUENCING AND ADHERING TO PROPER ATC PROCS WOULD HAVE PREVENTED THE SIT. I SPOKE WITH THE ATC SUPVR WHO ADMITTED THE TWR CTLR WAS A TRAINEE. BETTER SUPERVISION IS REQUIRED. FURTHERMORE, THE TWR CTLR EVIDENTLY THOUGHT WE WERE CLRED TO 2000 FT. THE BE1900 PLT ASKED WHAT ALT WE WERE ASSIGNED, AT WHICH POINT THE TWR CTLR SAID 2000 FT. TALKING WITH THE ATC SUPVR AFTER THE EVENT, HE SAID THE TWR CTLR WAS CONFUSED AND WE WERE CLRED TO 1500 FT. THE MARGINAL WX CONDITIONS CONTRIBUTED TO THE EVENT.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.