Narrative:

At cruising altitude 15000 ft, en route to jfk, ATC called VFR traffic 1 O'clock 10 SM 15500 ft 4 A10's. We spotted traffic visually. TCASII showed traffic at our altitude 15000 ft. We verified traffic with ATC. ATC responded 'traffic at 15500 ft.' we decided, based on visual reference, to descend. A10 leader suddenly initiated steep turn to the right. #2 and #3 A10's pulled up and crossed just in front of us. Did not see #4 A10. We descended +/-300 ft below assigned altitude. Clear of traffic, we climbed back to 15000 ft. Frequency very congested. A10's came out of the flight levels, local altimeter setting 30.47.

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Original NASA ASRS Text

Title: FLC OF A BAE 4100 DSNDED TO ASSURE SEPARATION WITH A FLT OF 4 MIL A10 ACFT DURING CRUISE. ARTCC PROVIDED TA OF VFR TFC 500 FT ABOVE.

Narrative: AT CRUISING ALT 15000 FT, ENRTE TO JFK, ATC CALLED VFR TFC 1 O'CLOCK 10 SM 15500 FT 4 A10'S. WE SPOTTED TFC VISUALLY. TCASII SHOWED TFC AT OUR ALT 15000 FT. WE VERIFIED TFC WITH ATC. ATC RESPONDED 'TFC AT 15500 FT.' WE DECIDED, BASED ON VISUAL REF, TO DSND. A10 LEADER SUDDENLY INITIATED STEEP TURN TO THE R. #2 AND #3 A10'S PULLED UP AND CROSSED JUST IN FRONT OF US. DID NOT SEE #4 A10. WE DSNDED +/-300 FT BELOW ASSIGNED ALT. CLR OF TFC, WE CLBED BACK TO 15000 FT. FREQ VERY CONGESTED. A10'S CAME OUT OF THE FLT LEVELS, LCL ALTIMETER SETTING 30.47.

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.