Narrative:

I was working an arrival sector for boston logan airport, pvd sector. I was providing extended intrail for bos arrs. Bdl departures traffic have a specific route, coastal 1 departure SID, which conflicts vertically with bos inbounds. I had an air carrier X, FL210, being handed off from the initial boston ARTCC sector, eastbound to bos. During this time, I was working air carrier Y coastal departure sbound, climbing to FL220. The preceding sector was sequencing air carrier X behind an air carrier Z to bos. Air carrier Z was turned over to my sector frequency without a handoff, which caused some confusion briefly. Not being aware that air carrier Z was preceding air carrier X I based climb control and turns on the fact that air carrier X should not be turned, since I assumed he was the only arrival to bos. The preceding sector, however, turned air carrier X to achieve intrail with air carrier Z and, by doing so, air carrier X was placed in conflict with air carrier Y. Both aircraft were turned, but separation was still lost, 4 mi. I believe this error would have not occurred if I was informed of air carrier Z inbound with the proper procedures from the preceding sector. My control actions were based on only the 1 aircraft crossing air carrier Y.

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Original NASA ASRS Text

Title: ACR X SAME ALT ASSIGNED HAD LTSS FROM ACR Y. SYS ERROR.

Narrative: I WAS WORKING AN ARR SECTOR FOR BOSTON LOGAN ARPT, PVD SECTOR. I WAS PROVIDING EXTENDED INTRAIL FOR BOS ARRS. BDL DEPS TFC HAVE A SPECIFIC RTE, COASTAL 1 DEP SID, WHICH CONFLICTS VERTLY WITH BOS INBOUNDS. I HAD AN ACR X, FL210, BEING HANDED OFF FROM THE INITIAL BOSTON ARTCC SECTOR, EBOUND TO BOS. DURING THIS TIME, I WAS WORKING ACR Y COASTAL DEP SBOUND, CLBING TO FL220. THE PRECEDING SECTOR WAS SEQUENCING ACR X BEHIND AN ACR Z TO BOS. ACR Z WAS TURNED OVER TO MY SECTOR FREQ WITHOUT A HDOF, WHICH CAUSED SOME CONFUSION BRIEFLY. NOT BEING AWARE THAT ACR Z WAS PRECEDING ACR X I BASED CLB CTL AND TURNS ON THE FACT THAT ACR X SHOULD NOT BE TURNED, SINCE I ASSUMED HE WAS THE ONLY ARR TO BOS. THE PRECEDING SECTOR, HOWEVER, TURNED ACR X TO ACHIEVE INTRAIL WITH ACR Z AND, BY DOING SO, ACR X WAS PLACED IN CONFLICT WITH ACR Y. BOTH ACFT WERE TURNED, BUT SEPARATION WAS STILL LOST, 4 MI. I BELIEVE THIS ERROR WOULD HAVE NOT OCCURRED IF I WAS INFORMED OF ACR Z INBOUND WITH THE PROPER PROCS FROM THE PRECEDING SECTOR. MY CTL ACTIONS WERE BASED ON ONLY THE 1 ACFT XING ACR Y.

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.