Narrative:

While working R26, I was holding 8000 ft through 14000 ft at bunts, inbound for phl. 8000 ft through 12000 ft was coordination with phl and were on phl frequency. Air carrier X was holding at 13000 ft on my frequency. Phl called and said air carrier Y, who was holding at 12000 ft, was out of the pattern and that 8000 ft was available. I observed a target in the pattern at 10000 ft and asked phl who that was. Phl responded it was air carrier Z and I was working him. I said I was not and then phl said air carrier Z was on his frequency and descending, which I told him I would descend air carrier X reference him. Unfortunately, air carrier west was right under air carrier X at 11000 ft that I could not see because of limited data block overlap. Phl did not advise me that this aircraft was still in the pattern and when I descended air carrier X to 9000 ft reference air carrier Z, air carrier X then informed me of a TCASII resolution and climbed to 11500 ft. Supplemental information from acn 606273: ZNY descended an aircraft on top of one I was holding at 11000 ft. He must have misunderstood who was still holding in the pattern. The pilot questioned who was descending above him and I issued a descent to my pilot and told him I would find out the situation. The problem can be corrected by having ZNY stop terminating radar service of aircraft in a holding pattern. They should continue monitoring aircraft in radar contact.

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Original NASA ASRS Text

Title: ZNY CTLR EXPERIENCED LOSS OF SEPARATION DURING HOLDING FOR PHL.

Narrative: WHILE WORKING R26, I WAS HOLDING 8000 FT THROUGH 14000 FT AT BUNTS, INBOUND FOR PHL. 8000 FT THROUGH 12000 FT WAS COORD WITH PHL AND WERE ON PHL FREQ. ACR X WAS HOLDING AT 13000 FT ON MY FREQ. PHL CALLED AND SAID ACR Y, WHO WAS HOLDING AT 12000 FT, WAS OUT OF THE PATTERN AND THAT 8000 FT WAS AVAILABLE. I OBSERVED A TARGET IN THE PATTERN AT 10000 FT AND ASKED PHL WHO THAT WAS. PHL RESPONDED IT WAS ACR Z AND I WAS WORKING HIM. I SAID I WAS NOT AND THEN PHL SAID ACR Z WAS ON HIS FREQ AND DSNDING, WHICH I TOLD HIM I WOULD DSND ACR X REF HIM. UNFORTUNATELY, ACR W WAS RIGHT UNDER ACR X AT 11000 FT THAT I COULD NOT SEE BECAUSE OF LIMITED DATA BLOCK OVERLAP. PHL DID NOT ADVISE ME THAT THIS ACFT WAS STILL IN THE PATTERN AND WHEN I DSNDED ACR X TO 9000 FT REF ACR Z, ACR X THEN INFORMED ME OF A TCASII RESOLUTION AND CLBED TO 11500 FT. SUPPLEMENTAL INFO FROM ACN 606273: ZNY DSNDED AN ACFT ON TOP OF ONE I WAS HOLDING AT 11000 FT. HE MUST HAVE MISUNDERSTOOD WHO WAS STILL HOLDING IN THE PATTERN. THE PLT QUESTIONED WHO WAS DSNDING ABOVE HIM AND I ISSUED A DSCNT TO MY PLT AND TOLD HIM I WOULD FIND OUT THE SIT. THE PROB CAN BE CORRECTED BY HAVING ZNY STOP TERMINATING RADAR SVC OF ACFT IN A HOLDING PATTERN. THEY SHOULD CONTINUE MONITORING ACFT IN RADAR CONTACT.

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.