Narrative:

We were cleared to cross art VOR at 3000 ft for an approach to watertown airport. At this time we were still talking to center. At 5 mi south of the VOR, center advised us to switch to advisory frequency, which I did. I announced our position and intentions. At the same time I was monitoring center on the other radio. At about this time, I noticed traffic on the TCASII at our 12 O'clock and 5 mi, 600 ft below us. At this time, a light plane came up on center frequency requesting to pick up an IFR from watertown. Center advised pilot he had just cleared aircraft into art and asked pilot's position. When advised of position, center seemed worried, for good reason. We were at 3000 ft, IMC, and the traffic on TCASII was now 12 O'clock and 2 mi, 200 ft below. I told first officer to turn wbound as I knew that there are no obstructions in that direction. While in the turn, TCASII issued a climb RA, which we followed. After this we completed the approach without incident. Cloud bases were at 2300 ft. Primary cause of conflict was not maintaining cloud clearance (500 ft below) by other pilot, and his failure to monitor advisory frequency.

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Original NASA ASRS Text

Title: POTENTIAL CONFLICT BTWN ARR DEP TFC.

Narrative: WE WERE CLRED TO CROSS ART VOR AT 3000 FT FOR AN APCH TO WATERTOWN ARPT. AT THIS TIME WE WERE STILL TALKING TO CTR. AT 5 MI S OF THE VOR, CTR ADVISED US TO SWITCH TO ADVISORY FREQ, WHICH I DID. I ANNOUNCED OUR POS AND INTENTIONS. AT THE SAME TIME I WAS MONITORING CTR ON THE OTHER RADIO. AT ABOUT THIS TIME, I NOTICED TFC ON THE TCASII AT OUR 12 O'CLOCK AND 5 MI, 600 FT BELOW US. AT THIS TIME, A LIGHT PLANE CAME UP ON CTR FREQ REQUESTING TO PICK UP AN IFR FROM WATERTOWN. CTR ADVISED PLT HE HAD JUST CLRED ACFT INTO ART AND ASKED PLT'S POS. WHEN ADVISED OF POS, CTR SEEMED WORRIED, FOR GOOD REASON. WE WERE AT 3000 FT, IMC, AND THE TFC ON TCASII WAS NOW 12 O'CLOCK AND 2 MI, 200 FT BELOW. I TOLD FO TO TURN WBOUND AS I KNEW THAT THERE ARE NO OBSTRUCTIONS IN THAT DIRECTION. WHILE IN THE TURN, TCASII ISSUED A CLB RA, WHICH WE FOLLOWED. AFTER THIS WE COMPLETED THE APCH WITHOUT INCIDENT. CLOUD BASES WERE AT 2300 FT. PRIMARY CAUSE OF CONFLICT WAS NOT MAINTAINING CLOUD CLRNC (500 FT BELOW) BY OTHER PLT, AND HIS FAILURE TO MONITOR ADVISORY FREQ.

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.