Narrative:

On mar/xa/06 at XA59Z; I was providing training on yardley sector with the pottstown sector combined. We had about 10 aircraft on the frequency with 3 of them doing special activities (VFR box hot at nxx; photo mission aircraft off ttn; flight check aircraft inbound to nxx and law enforcement aircraft on station north of pne). We had just taken a briefing and developmental descended aircraft X out of 4000 ft; with aircraft Y behind him at 3000 ft. This happened in the first min when the instructor (me) was not even plugged in.

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Original NASA ASRS Text

Title: PHL CTLR HAD AN OPERROR AT APPROX 3500 FT BTWN AN ACR ACFT AND A FLT CHK ACFT DURING RELIEF BRIEFING. DEVELOPMENTAL CTLR DSNDED TFC THROUGH OCCUPIED ALT.

Narrative: ON MAR/XA/06 AT XA59Z; I WAS PROVIDING TRAINING ON YARDLEY SECTOR WITH THE POTTSTOWN SECTOR COMBINED. WE HAD ABOUT 10 ACFT ON THE FREQ WITH 3 OF THEM DOING SPECIAL ACTIVITIES (VFR BOX HOT AT NXX; PHOTO MISSION ACFT OFF TTN; FLT CHK ACFT INBOUND TO NXX AND LAW ENFORCEMENT ACFT ON STATION N OF PNE). WE HAD JUST TAKEN A BRIEFING AND DEVELOPMENTAL DSNDED ACFT X OUT OF 4000 FT; WITH ACFT Y BEHIND HIM AT 3000 FT. THIS HAPPENED IN THE FIRST MIN WHEN THE INSTRUCTOR (ME) WAS NOT EVEN PLUGGED IN.

Data retrieved from NASA's ASRS site as of January 2009 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.