Narrative:

We were at level cruise at 11000 ft about 10 NM north of rmg VOR, heading south on a flight from cha to atl. I was giving instruction to a new captain, so I was in the right seat, but was PIC. I was doing some paperwork when I looked left and saw a blue and white cessna 182 at our 10 O'clock position and probably less than 500 ft horizontal separation and zero ft vertical. The cessna appeared to be heading toward the southwest, and we were heading south. I turned off the autoplt and turned to the right to miss the aircraft. We estimated that we missed the aircraft by about 200 ft. We then called center and advised them of the conflict, and they said that they showed no traffic. We were TCASII equipped, and our TCASII never showed the aircraft either. After landing in atl, we called atl center and talked with a supervisor. He informed us that he was standing behind the controller when the near miss occurred, and verified that no traffic was showing until after we reported the conflict, then they showed up and the pilot of the cessna called for flight following. The controller also said they mentioned to the cessna the dangers of flying 50 mi outside one of the busiest airports in the world at 11000 ft without a transponder on and without talking with anyone.

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Original NASA ASRS Text

Title: ATR72 LEVEL AT 11000 WITH ZTL ARTCC RPTED CONFLICTING VFR C182.

Narrative: WE WERE AT LEVEL CRUISE AT 11000 FT ABOUT 10 NM N OF RMG VOR, HEADING S ON A FLT FROM CHA TO ATL. I WAS GIVING INSTRUCTION TO A NEW CAPT, SO I WAS IN THE R SEAT, BUT WAS PIC. I WAS DOING SOME PAPERWORK WHEN I LOOKED L AND SAW A BLUE AND WHITE CESSNA 182 AT OUR 10 O'CLOCK POS AND PROBABLY LESS THAN 500 FT HORIZ SEPARATION AND ZERO FT VERT. THE CESSNA APPEARED TO BE HEADING TOWARD THE SW, AND WE WERE HEADING S. I TURNED OFF THE AUTOPLT AND TURNED TO THE R TO MISS THE ACFT. WE ESTIMATED THAT WE MISSED THE ACFT BY ABOUT 200 FT. WE THEN CALLED CTR AND ADVISED THEM OF THE CONFLICT, AND THEY SAID THAT THEY SHOWED NO TFC. WE WERE TCASII EQUIPPED, AND OUR TCASII NEVER SHOWED THE ACFT EITHER. AFTER LNDG IN ATL, WE CALLED ATL CTR AND TALKED WITH A SUPVR. HE INFORMED US THAT HE WAS STANDING BEHIND THE CTLR WHEN THE NEAR MISS OCCURRED, AND VERIFIED THAT NO TFC WAS SHOWING UNTIL AFTER WE RPTED THE CONFLICT, THEN THEY SHOWED UP AND THE PLT OF THE CESSNA CALLED FOR FLT FOLLOWING. THE CTLR ALSO SAID THEY MENTIONED TO THE CESSNA THE DANGERS OF FLYING 50 MI OUTSIDE ONE OF THE BUSIEST ARPTS IN THE WORLD AT 11000 FT WITHOUT A XPONDER ON AND WITHOUT TALKING WITH ANYONE.

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.