Narrative:

On a scheduled flight from evansville, in, to paducah, ky, we were flying at 2500' MSL, where ZME had cleared us in preparation for a visibility approach to pah. We were waiting for our clearance for a visibility approach and a handoff to the pah tower so we could descend and land straight in on runway 22. As we got within about 5 mi of the airport, center called us with traffic 12 O'clock at our altitude. I looked up to check for the traffic, but saw nothing. I then looked back in the cockpit to do some prelndg chores for a few seconds and center called back with traffic at 12 O'clock, 1 mi, at 2500'. I immediately looked out and after a few seconds I saw a single engine small aircraft appear motionless at 12 O'clock at our altitude, but getting larger fast. I grabbed the control wheel to start a left turn and I said to my first officer, 'traffic 12 O'clock.' almost at the same time he started a left diving turn to avoid the traffic. As the aircraft rolled to about 30 degree of bank, I saw the single engine small aircraft make a steep left turn to avoid us. I asked center about the traffic and center said he was pop-up traffic. I asked the pah tower about the traffic and he knew nothing about him. While the small aircraft had a right to be in the airspace, he was illegal because he was in the pah air traffic area and not talking to the pah tower. After turning back toward runway 22 after our evasive action, we were too close to be able to land on runway 22 straight ahead. We continued on to land on runway 4.

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Original NASA ASRS Text

Title: NMAC BETWEEN LTT ON IFR IN VMC AND UNIDENTIFIED SMA. POSSIBLY TOOK PLACE IN ATA.

Narrative: ON A SCHEDULED FLT FROM EVANSVILLE, IN, TO PADUCAH, KY, WE WERE FLYING AT 2500' MSL, WHERE ZME HAD CLRED US IN PREPARATION FOR A VIS APCH TO PAH. WE WERE WAITING FOR OUR CLRNC FOR A VIS APCH AND A HDOF TO THE PAH TWR SO WE COULD DSND AND LAND STRAIGHT IN ON RWY 22. AS WE GOT WITHIN ABOUT 5 MI OF THE ARPT, CENTER CALLED US WITH TFC 12 O'CLOCK AT OUR ALT. I LOOKED UP TO CHK FOR THE TFC, BUT SAW NOTHING. I THEN LOOKED BACK IN THE COCKPIT TO DO SOME PRELNDG CHORES FOR A FEW SECS AND CENTER CALLED BACK WITH TFC AT 12 O'CLOCK, 1 MI, AT 2500'. I IMMEDIATELY LOOKED OUT AND AFTER A FEW SECS I SAW A SINGLE ENG SMA APPEAR MOTIONLESS AT 12 O'CLOCK AT OUR ALT, BUT GETTING LARGER FAST. I GRABBED THE CONTROL WHEEL TO START A LEFT TURN AND I SAID TO MY F/O, 'TFC 12 O'CLOCK.' ALMOST AT THE SAME TIME HE STARTED A LEFT DIVING TURN TO AVOID THE TFC. AS THE ACFT ROLLED TO ABOUT 30 DEG OF BANK, I SAW THE SINGLE ENG SMA MAKE A STEEP LEFT TURN TO AVOID US. I ASKED CENTER ABOUT THE TFC AND CENTER SAID HE WAS POP-UP TFC. I ASKED THE PAH TWR ABOUT THE TFC AND HE KNEW NOTHING ABOUT HIM. WHILE THE SMA HAD A RIGHT TO BE IN THE AIRSPACE, HE WAS ILLEGAL BECAUSE HE WAS IN THE PAH ATA AND NOT TALKING TO THE PAH TWR. AFTER TURNING BACK TOWARD RWY 22 AFTER OUR EVASIVE ACTION, WE WERE TOO CLOSE TO BE ABLE TO LAND ON RWY 22 STRAIGHT AHEAD. WE CONTINUED ON TO LAND ON RWY 4.

Data retrieved from NASA's ASRS site as of August 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.