Narrative:

F15 flight (4 aircraft) cleared to 6000 ft. C172 northbound level flight at 7000 ft. Traffic was called to both aircraft. F15 flight mode C observed at 6200 ft. Another clearance to maintain 6000 ft was issued. Mode C at 6500 ft then observed. I asked F15 flight to verify at 6000 ft at which point the pilot stated that he was correcting. No evasive action taken by either aircraft. (Center computer caught loss of separation and statements were filed.)

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Original NASA ASRS Text

Title: ARTCC CTLR OBSERVED A FLT OF F15 ACFT OVERSHOOT THEIR ASSIGNED ALT OF 6000 FT AND CREATE LTSS WITH A C172 IN CRUISE AT 7000 FT. CTLR ADVISED THE F15 FLT OF HIS TFC AND REASSIGNED 6000 FT AND THEN VERIFIED THAT THE CLRNC WAS UNDERSTOOD. CONFLICT ALERT PICKED UP THE LTSS INCIDENT. TA WAS ALSO GIVEN TO THE C172.

Narrative: F15 FLT (4 ACFT) CLRED TO 6000 FT. C172 NBOUND LEVEL FLT AT 7000 FT. TFC WAS CALLED TO BOTH ACFT. F15 FLT MODE C OBSERVED AT 6200 FT. ANOTHER CLRNC TO MAINTAIN 6000 FT WAS ISSUED. MODE C AT 6500 FT THEN OBSERVED. I ASKED F15 FLT TO VERIFY AT 6000 FT AT WHICH POINT THE PLT STATED THAT HE WAS CORRECTING. NO EVASIVE ACTION TAKEN BY EITHER ACFT. (CTR COMPUTER CAUGHT LOSS OF SEPARATION AND STATEMENTS WERE FILED.)

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.