Narrative:

We were en route direct sps (departed dfw), level 8000 ft. First officer was at controls. First officer saw another aircraft at our 10:30 position and made a slight, shallow right bank (less than 15 degree bank). I did not see aircraft until our aircraft banked due to side window post. The other aircraft was definitely at our altitude and approaching. Though the aircraft passed within 500 ft of us, it was not going to hit us. As the aircraft passed behind us, I asked ZFW if he saw the traffic pass by us. He replied yes, that he had a primary target. I informed him it was an small aircraft sel aircraft, level at 8000 ft. I guess what I'm trying to say is, if the controller saw the target that close to us, why not tell us. Primary target or not.

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Original NASA ASRS Text

Title: FLC OF ACR LTT ACFT TOOK EVASIVE ACTION TO AVOID OTHER OBSERVED TFC AND TURNED OFF ASSIGNED HDG.

Narrative: WE WERE ENRTE DIRECT SPS (DEPARTED DFW), LEVEL 8000 FT. FO WAS AT CTLS. FO SAW ANOTHER ACFT AT OUR 10:30 POS AND MADE A SLIGHT, SHALLOW R BANK (LESS THAN 15 DEG BANK). I DID NOT SEE ACFT UNTIL OUR ACFT BANKED DUE TO SIDE WINDOW POST. THE OTHER ACFT WAS DEFINITELY AT OUR ALT AND APCHING. THOUGH THE ACFT PASSED WITHIN 500 FT OF US, IT WAS NOT GOING TO HIT US. AS THE ACFT PASSED BEHIND US, I ASKED ZFW IF HE SAW THE TFC PASS BY US. HE REPLIED YES, THAT HE HAD A PRIMARY TARGET. I INFORMED HIM IT WAS AN SMA SEL ACFT, LEVEL AT 8000 FT. I GUESS WHAT I'M TRYING TO SAY IS, IF THE CTLR SAW THE TARGET THAT CLOSE TO US, WHY NOT TELL US. PRIMARY TARGET OR NOT.

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.