Narrative:

I was cruising at 6500 ft in contact with atlanta approach in VFR conditions. Traffic was given at 4-5 O'clock position, 6000 ft. I notified the controller I had traffic in sight. As I watched the traffic and it got closer, it appeared to be climbing. It was approaching quickly and I know I could not out climb the traffic. I therefore disengaged my autoplt and descended to 5500 ft. At this time, the traffic took evasive action also by turning to the left and away from me. The traffic passed behind me after the action was taken. The traffic was a large military plane. I could hear only the controller's side of the conversation with the military plane. I heard the controller say to the military plane (I do not know why he did that), which I figure was relating to my changing of altitudes. The controller then asked me whom I filed my flight plan with. I told him I had not filed a flight plan, but asked for flight following with ZJX and was handed off to him by ZJX. He then asked where my home base was, and I told him. I feel being unable to hear the conversation between the controller and the military plane created a very uneasy situation. I have never had a plane that big fly under me at 500 ft between planes. I did not know if the military plane had me in sight because of the different communication frequency. I feel the military plane could have changed course about 20 degrees to the left and passed behind me with no problem.

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Original NASA ASRS Text

Title: A GA PLT'S FIRST ENCOUNTER WITH A LARGE MIL ACFT IN CLOSE PROX ON A DIFFERENT FREQ CAUSES HIM CONCERN.

Narrative: I WAS CRUISING AT 6500 FT IN CONTACT WITH ATLANTA APCH IN VFR CONDITIONS. TFC WAS GIVEN AT 4-5 O'CLOCK POS, 6000 FT. I NOTIFIED THE CTLR I HAD TFC IN SIGHT. AS I WATCHED THE TFC AND IT GOT CLOSER, IT APPEARED TO BE CLBING. IT WAS APCHING QUICKLY AND I KNOW I COULD NOT OUT CLB THE TFC. I THEREFORE DISENGAGED MY AUTOPLT AND DSNDED TO 5500 FT. AT THIS TIME, THE TFC TOOK EVASIVE ACTION ALSO BY TURNING TO THE L AND AWAY FROM ME. THE TFC PASSED BEHIND ME AFTER THE ACTION WAS TAKEN. THE TFC WAS A LARGE MIL PLANE. I COULD HEAR ONLY THE CTLR'S SIDE OF THE CONVERSATION WITH THE MIL PLANE. I HEARD THE CTLR SAY TO THE MIL PLANE (I DO NOT KNOW WHY HE DID THAT), WHICH I FIGURE WAS RELATING TO MY CHANGING OF ALTS. THE CTLR THEN ASKED ME WHOM I FILED MY FLT PLAN WITH. I TOLD HIM I HAD NOT FILED A FLT PLAN, BUT ASKED FOR FLT FOLLOWING WITH ZJX AND WAS HANDED OFF TO HIM BY ZJX. HE THEN ASKED WHERE MY HOME BASE WAS, AND I TOLD HIM. I FEEL BEING UNABLE TO HEAR THE CONVERSATION BTWN THE CTLR AND THE MIL PLANE CREATED A VERY UNEASY SIT. I HAVE NEVER HAD A PLANE THAT BIG FLY UNDER ME AT 500 FT BTWN PLANES. I DID NOT KNOW IF THE MIL PLANE HAD ME IN SIGHT BECAUSE OF THE DIFFERENT COM FREQ. I FEEL THE MIL PLANE COULD HAVE CHANGED COURSE ABOUT 20 DEGS TO THE L AND PASSED BEHIND ME WITH NO PROB.

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.