Narrative:

A routine flight from gainesville, fl, to orlando. We were vectored from leese intersection to a 14 mi final at executive airport landing on runway 7. Approach cleared us for an ILS to 7. Maintain 2000' until the marker. After the handoff to the tower it took several mi to make contact with executive tower. We made contact with the tower 2 mi outside the marker and were told to continue straight in to runway 7. 1 mi inside the marker I spotted an small aircraft a at our 11:30 position traveling outbnd on the localizer. I leveled off and within seconds small aircraft a went underneath us at 150-200' vertical, no horizontal sep. The aircraft was a skywatch aircraft who had been reporting on surface traffic conditions. Apparently he was west of the airport inbound to land. He was instructed by the tower (prior to our handoff to the tower) to fly inbound to the airport and sequence himself behind. Small aircraft B who was supposed to be on a midfield downwind. Small aircraft B was confused and turned base when he was supposed to stay on downwind. After this happened the tower instructed small aircraft B to come toward the runway and land. Skywatch was instructed to continue (rejoin?) downwind and follow the small aircraft B. Skywatch was not on downwind, however he was on the extended centerline of the localizer and passed 150-200' below us, only after I leveled off upon sighting him. After the near miss, my first officer asked the tower if he knew of the aircraft in our area.

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Original NASA ASRS Text

Title: CLOSE PROX CPR-LTT GA-SMA IN ORL ATA.

Narrative: A ROUTINE FLT FROM GAINESVILLE, FL, TO ORLANDO. WE WERE VECTORED FROM LEESE INTXN TO A 14 MI FINAL AT EXECUTIVE ARPT LNDG ON RWY 7. APCH CLRED US FOR AN ILS TO 7. MAINTAIN 2000' UNTIL THE MARKER. AFTER THE HDOF TO THE TWR IT TOOK SEVERAL MI TO MAKE CONTACT WITH EXECUTIVE TWR. WE MADE CONTACT WITH THE TWR 2 MI OUTSIDE THE MARKER AND WERE TOLD TO CONTINUE STRAIGHT IN TO RWY 7. 1 MI INSIDE THE MARKER I SPOTTED AN SMA A AT OUR 11:30 POS TRAVELING OUTBND ON THE LOC. I LEVELED OFF AND WITHIN SECS SMA A WENT UNDERNEATH US AT 150-200' VERT, NO HORIZ SEP. THE ACFT WAS A SKYWATCH ACFT WHO HAD BEEN RPTING ON SURFACE TFC CONDITIONS. APPARENTLY HE WAS W OF THE ARPT INBND TO LAND. HE WAS INSTRUCTED BY THE TWR (PRIOR TO OUR HDOF TO THE TWR) TO FLY INBND TO THE ARPT AND SEQUENCE HIMSELF BEHIND. SMA B WHO WAS SUPPOSED TO BE ON A MIDFIELD DOWNWIND. SMA B WAS CONFUSED AND TURNED BASE WHEN HE WAS SUPPOSED TO STAY ON DOWNWIND. AFTER THIS HAPPENED THE TWR INSTRUCTED SMA B TO COME TOWARD THE RWY AND LAND. SKYWATCH WAS INSTRUCTED TO CONTINUE (REJOIN?) DOWNWIND AND FOLLOW THE SMA B. SKYWATCH WAS NOT ON DOWNWIND, HOWEVER HE WAS ON THE EXTENDED CENTERLINE OF THE LOC AND PASSED 150-200' BELOW US, ONLY AFTER I LEVELED OFF UPON SIGHTING HIM. AFTER THE NEAR MISS, MY F/O ASKED THE TWR IF HE KNEW OF THE ACFT IN OUR AREA.

Data retrieved from NASA's ASRS site as of August 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.