Narrative:

While in cruise at 13000 ft, VMC, autoplt on, first officer's leg, we received a TCASII TA with an aircraft at our 1 O'clock position, climbing at 1200 ft below us. We did not see the traffic, and the aircraft continued to climb. When the aircraft was 800 ft below us, I told the first officer to 'get ready.' about 3 seconds later, we received an RA to climb. A climb was immediately initiated, and I then spotted the traffic coming at us and climbing. I called 'my controls' and initiated a hard left turn to avoid the traffic. TCASII then advised us to 'descend,' and I initiated a descent. We observed the traffic, a T38, pass off our right wing, and I looked at the TCASII and he was +01, or 100 ft above us and still climbing. We then advised ATC we had responded to an RA, and returning to 13000 ft. ATC said, 'wow, I didn't think that was going to be a problem. He was at 8000 ft and not climbing fast and then he just shot up.' flight continued to destination after talking with the flight attendants to make sure everyone was fine. We were approximately 20 mi west of lgc on the arrival, on frequency 120.45(?), and ATC never told us look for traffic or anything about traffic. I advised ATC that it was 'the closest I have been to another aircraft in atl airspace.' when the traffic passed, he was approximately 1/8 mi away, and +100 ft above us.

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Original NASA ASRS Text

Title: IFR AT72 AT 13000 FT EXPERIENCED TCASII RA WITH T38 IN A80 AIRSPACE.

Narrative: WHILE IN CRUISE AT 13000 FT, VMC, AUTOPLT ON, FO'S LEG, WE RECEIVED A TCASII TA WITH AN ACFT AT OUR 1 O'CLOCK POS, CLBING AT 1200 FT BELOW US. WE DID NOT SEE THE TFC, AND THE ACFT CONTINUED TO CLB. WHEN THE ACFT WAS 800 FT BELOW US, I TOLD THE FO TO 'GET READY.' ABOUT 3 SECONDS LATER, WE RECEIVED AN RA TO CLB. A CLB WAS IMMEDIATELY INITIATED, AND I THEN SPOTTED THE TFC COMING AT US AND CLBING. I CALLED 'MY CTLS' AND INITIATED A HARD L TURN TO AVOID THE TFC. TCASII THEN ADVISED US TO 'DSND,' AND I INITIATED A DSCNT. WE OBSERVED THE TFC, A T38, PASS OFF OUR R WING, AND I LOOKED AT THE TCASII AND HE WAS +01, OR 100 FT ABOVE US AND STILL CLBING. WE THEN ADVISED ATC WE HAD RESPONDED TO AN RA, AND RETURNING TO 13000 FT. ATC SAID, 'WOW, I DIDN'T THINK THAT WAS GOING TO BE A PROB. HE WAS AT 8000 FT AND NOT CLBING FAST AND THEN HE JUST SHOT UP.' FLT CONTINUED TO DEST AFTER TALKING WITH THE FLT ATTENDANTS TO MAKE SURE EVERYONE WAS FINE. WE WERE APPROX 20 MI W OF LGC ON THE ARR, ON FREQ 120.45(?), AND ATC NEVER TOLD US LOOK FOR TFC OR ANYTHING ABOUT TFC. I ADVISED ATC THAT IT WAS 'THE CLOSEST I HAVE BEEN TO ANOTHER ACFT IN ATL AIRSPACE.' WHEN THE TFC PASSED, HE WAS APPROX 1/8 MI AWAY, AND +100 FT ABOVE US.

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.