NMAC BTWN SF34 AND AIR TRACTOR AT 8000 FT OVER UJM VOR.

Narrative

WHILE LEVEL AT 8000 FT NEAR THE MARVELL VOR (UJM); WE EXPERIENCED AN NMAC WITH AN AIR TRACTOR TURBOPROP CROP DUSTER. THE OTHER ACFT WAS COMING FROM OUR 11 O'CLOCK POS; AND TRAVELING NW TO SE. IT PASSED 300-500 FT IN FRONT OF OUR ACFT AND 0-100 FT ABOVE OUR ALT. THE AIR TRACTOR WAS SO CLOSE THAT WE COULD FEEL ITS WAKE TURB AS IT WENT BY. OUR TCAS WAS OPERATING AND SHOWED NO OTHER ACFT AND ATC; MEMPHIS APCH CTL; GAVE NO TFC WARNINGS. WE WERE NOT ABLE TO SEE THE N-NUMBER AS THE ACFT PASSED BY VERY QUICKLY. NO EVASIVE ACTION WAS TAKEN AS THE ENCOUNTER WAS OVER BEFORE WE COULD TAKE ANY. I CALLED MEM APCH CTL AND RPTED THE INCIDENT; AND LATER TALKED WITH A SUPVR AND GAVE FURTHER DETAILS. I ALSO CALLED DISPATCH AND SPOKE WITH THE DISPATCH MGR AS WELL AS A FLT MGR. THERE WERE NO INJURIES TO CREW OR PAX. WE BELIEVE THAT WE WERE DOING EVERYTHING CORRECTLY AT THE TIME OF THE INCIDENT. ALL OF OUR CHKLISTS WERE COMPLETE AND THERE WAS VERY LITTLE DISTR FROM INSIDE OUR COCKPIT. WE HAD FOLLOWED ALL ATC INSTRUCTIONS AND THE ACFT WAS IN THE CORRECT LOCATION FOR OUR FLT PLAN AND ATC GUIDANCE. IT IS POSSIBLE THAT THE AIR TRACTOR WAS BLOCKED BY MY SUN VISOR AND POSSIBLY THE WINDOW PILLAR; AS THIS CREATES A BLIND SPOT IN THE COCKPIT FROM THE DIRECTION THAT THE OTHER ACFT WAS TRAVELING. THAT ACFT WAS ALSO COMING AT US FROM THE SUN AND AT THE WRONG ALT FOR DIRECTION OF FLT. ALTHOUGH WE HAD ALL OF OUR EXTERIOR LIGHTS ON; AND WERE FOLLOWING INSTRUCTIONS AND SOP; IT'S ALWAYS NECESSARY TO WATCH OUT FOR 'THE OTHER GUY' WHO IS HAVING A BAD DAY. SEE AND AVOID; EVEN IF TCAS IS INSTALLED AND UNDER ATC CTL IS EVERY PLT'S RESPONSIBILITY.