Narrative:

As a developmental approach controller, I was training on the dupont low sector at phl approach. I was working several IFR aircraft inbound to ilg for the ILS runway 1 approach. I was also working small aircraft X southbound on V29 from dqo to eno at 6000'. I initiated an ARTS handoff to dov approach on small aircraft X, and they accepted it. I then instructed X to contact dov approach, and the pilot acknowledged. A few moments later dov approach called on the landline with 2 handoffs, mlt Y at 5000', and also an small transport at 5000'. I had radar contact on both aircraft and accepted both handoffs. While I was accepting the handoff on mlt Y I remember looking at small aircraft X target on my scope and reconfirming the fact that he was at 6000'. When Y called, I climbed him to 6000' (opp direction to X), forgetting all about X, whom I was aware of only seconds before. When I observed mlt Y's altitude, and realized he was climbing out of 5200', I suddenly remembered small aircraft X and realized my error. I instructed Y to turn away from the traffic and descend immediately to 5000', which he did. But by then, IFR sep had already been lost. I don't know why I forgot about aircraft X only seconds after I reconfirmed his position and altitude in my mind while accepting the handoff on mlt Y. Apparently I was more concerned with my ilg arrival traffic, feeling that my time spent coordinating with dov approach on the landline had put me behind. My forgetting about aircraft X and failure to scan the area surrounding mlt Y properly before issuing the climb instruction were the causes of this system error.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN SMA AND MIL TRANSPORT. OPERATIONAL ERROR.

Narrative: AS A DEVELOPMENTAL APCH CTLR, I WAS TRNING ON THE DUPONT LOW SECTOR AT PHL APCH. I WAS WORKING SEVERAL IFR ACFT INBND TO ILG FOR THE ILS RWY 1 APCH. I WAS ALSO WORKING SMA X SBND ON V29 FROM DQO TO ENO AT 6000'. I INITIATED AN ARTS HDOF TO DOV APCH ON SMA X, AND THEY ACCEPTED IT. I THEN INSTRUCTED X TO CONTACT DOV APCH, AND THE PLT ACKNOWLEDGED. A FEW MOMENTS LATER DOV APCH CALLED ON THE LANDLINE WITH 2 HDOFS, MLT Y AT 5000', AND ALSO AN SMT AT 5000'. I HAD RADAR CONTACT ON BOTH ACFT AND ACCEPTED BOTH HDOFS. WHILE I WAS ACCEPTING THE HDOF ON MLT Y I REMEMBER LOOKING AT SMA X TARGET ON MY SCOPE AND RECONFIRMING THE FACT THAT HE WAS AT 6000'. WHEN Y CALLED, I CLBED HIM TO 6000' (OPP DIRECTION TO X), FORGETTING ALL ABOUT X, WHOM I WAS AWARE OF ONLY SECS BEFORE. WHEN I OBSERVED MLT Y'S ALT, AND REALIZED HE WAS CLBING OUT OF 5200', I SUDDENLY REMEMBERED SMA X AND REALIZED MY ERROR. I INSTRUCTED Y TO TURN AWAY FROM THE TFC AND DSND IMMEDIATELY TO 5000', WHICH HE DID. BUT BY THEN, IFR SEP HAD ALREADY BEEN LOST. I DON'T KNOW WHY I FORGOT ABOUT ACFT X ONLY SECS AFTER I RECONFIRMED HIS POS AND ALT IN MY MIND WHILE ACCEPTING THE HDOF ON MLT Y. APPARENTLY I WAS MORE CONCERNED WITH MY ILG ARR TFC, FEELING THAT MY TIME SPENT COORDINATING WITH DOV APCH ON THE LANDLINE HAD PUT ME BEHIND. MY FORGETTING ABOUT ACFT X AND FAILURE TO SCAN THE AREA SURROUNDING MLT Y PROPERLY BEFORE ISSUING THE CLB INSTRUCTION WERE THE CAUSES OF THIS SYS ERROR.

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.