Narrative:

We were descending out of 11000 to 5000 on assigned heading but cleared to deviate around buildups. At 8000 ft, we saw a military fgt in front of us at our altitude moving in the opposite direction. Before I could begin evasive action to miss the aircraft, he passed off of our left wing so close that we could clearly see the pilot's mask and fine details of the aircraft itself. We asked ATC about the aircraft and they said they had nothing on him and to turn right. After turning we asked again about the fgt and the controller said that he must be VFR, that he is picking him up intermittently on radar. The next controller's comments were from a different controller on the same frequency clearing us for the approach. The horizontal distance, I found hard to estimate, but in my 5000 hours of flying, it was the closest I had ever been to another aircraft in-flight.

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Original NASA ASRS Text

Title: NMAC IN VICINITY OF A MIL LOW LEVEL INST TRAINING RTE (IR) BTWN ACR LTT AND MIL FGT.

Narrative: WE WERE DSNDING OUT OF 11000 TO 5000 ON ASSIGNED HDG BUT CLRED TO DEVIATE AROUND BUILDUPS. AT 8000 FT, WE SAW A MIL FGT IN FRONT OF US AT OUR ALT MOVING IN THE OPPOSITE DIRECTION. BEFORE I COULD BEGIN EVASIVE ACTION TO MISS THE ACFT, HE PASSED OFF OF OUR L WING SO CLOSE THAT WE COULD CLRLY SEE THE PLT'S MASK AND FINE DETAILS OF THE ACFT ITSELF. WE ASKED ATC ABOUT THE ACFT AND THEY SAID THEY HAD NOTHING ON HIM AND TO TURN R. AFTER TURNING WE ASKED AGAIN ABOUT THE FGT AND THE CTLR SAID THAT HE MUST BE VFR, THAT HE IS PICKING HIM UP INTERMITTENTLY ON RADAR. THE NEXT CTLR'S COMMENTS WERE FROM A DIFFERENT CTLR ON THE SAME FREQ CLRING US FOR THE APCH. THE HORIZ DISTANCE, I FOUND HARD TO ESTIMATE, BUT IN MY 5000 HRS OF FLYING, IT WAS THE CLOSEST I HAD EVER BEEN TO ANOTHER ACFT INFLT.

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.