Narrative:

I accepted handoffs on a flight of 3 T45's inbound to mei and a C550 that had departed mei. The T45's were about 20 mi north of the airport and were given a 180 degree heading and a descent to 4000 ft. The C550 was about 5 mi north of the airport level at 7000 ft. The T45's were descending out of 8000 ft. The T45's did not descend at a normal rate and did not advise they were doing so. They leveled off at 6300 ft for approximately 2 1/2 mi. While in the process of passing the inbound strip to the next controller; I noticed they weren't going to make the descent. I then issued a corrective action turn to the northwest of the C550 and he advised his TCAS was 'going off.' I then notified my supervisor.

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Original NASA ASRS Text

Title: NMM TRACON CTLR EXPERIENCED LOSS OF SEPARATION AT APPROX 6500 FT WHEN MIL FLT OF T45'S DSNDED SLOWER THAN EXPECTED AND CONFLICTED WITH DEP ACFT.

Narrative: I ACCEPTED HDOFS ON A FLT OF 3 T45'S INBOUND TO MEI AND A C550 THAT HAD DEPARTED MEI. THE T45'S WERE ABOUT 20 MI N OF THE ARPT AND WERE GIVEN A 180 DEG HDG AND A DSCNT TO 4000 FT. THE C550 WAS ABOUT 5 MI N OF THE ARPT LEVEL AT 7000 FT. THE T45'S WERE DSNDING OUT OF 8000 FT. THE T45'S DID NOT DSND AT A NORMAL RATE AND DID NOT ADVISE THEY WERE DOING SO. THEY LEVELED OFF AT 6300 FT FOR APPROX 2 1/2 MI. WHILE IN THE PROCESS OF PASSING THE INBOUND STRIP TO THE NEXT CTLR; I NOTICED THEY WEREN'T GOING TO MAKE THE DSCNT. I THEN ISSUED A CORRECTIVE ACTION TURN TO THE NW OF THE C550 AND HE ADVISED HIS TCAS WAS 'GOING OFF.' I THEN NOTIFIED MY SUPVR.

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.