Narrative:

On sep/sat/89, at approximately mid pm local, I was piloting an medium large transport from clt to avl. We were level, heading wnw (290 degree) at 10,000', when radar called VFR traffic at 12-1 O'clock, 10-12 mi at approximately our altitude. After 15-20 seconds, we visually acquired the small, single engine propeller heading approximately 190 degree at approximately 10,500'. We advised ATC that we had the traffic in sight and they cleared us to 'maintain visual separation' and switch to the next sector frequency. As I maintained contact with the small aircraft and the first officer handled the sector frequency shift, I observed the small plane commence a standard rate, descending left turn, directly toward an intersecting point along our flight path. The new sector was issuing radar warnings to us as we continued to observe the small plane descend to our flight level. I reduced power and descended 200-300'. The small plane passed directly overhead at a close but undetermined distance. I then climbed back to my altitude and thanked the controllers for their aggressive traffic callouts. I don't think the small aircraft did anything wrong. As he changed heading he descended to the appropriate sector altitude. His only problem was that he didn't see us. Without the radar warnings we would have had a very exciting incident.

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Original NASA ASRS Text

Title: NMAC.

Narrative: ON SEP/SAT/89, AT APPROX MID PM LOCAL, I WAS PILOTING AN MLG FROM CLT TO AVL. WE WERE LEVEL, HDG WNW (290 DEG) AT 10,000', WHEN RADAR CALLED VFR TFC AT 12-1 O'CLOCK, 10-12 MI AT APPROX OUR ALT. AFTER 15-20 SECONDS, WE VISUALLY ACQUIRED THE SMALL, SINGLE ENGINE PROPELLER HDG APPROX 190 DEG AT APPROX 10,500'. WE ADVISED ATC THAT WE HAD THE TFC IN SIGHT AND THEY CLRED US TO 'MAINTAIN VISUAL SEPARATION' AND SWITCH TO THE NEXT SECTOR FREQ. AS I MAINTAINED CONTACT WITH THE SMALL ACFT AND THE F/O HANDLED THE SECTOR FREQ SHIFT, I OBSERVED THE SMALL PLANE COMMENCE A STANDARD RATE, DESCENDING LEFT TURN, DIRECTLY TOWARD AN INTERSECTING POINT ALONG OUR FLT PATH. THE NEW SECTOR WAS ISSUING RADAR WARNINGS TO US AS WE CONTINUED TO OBSERVE THE SMALL PLANE DSND TO OUR FLT LEVEL. I REDUCED POWER AND DESCENDED 200-300'. THE SMALL PLANE PASSED DIRECTLY OVERHEAD AT A CLOSE BUT UNDETERMINED DISTANCE. I THEN CLIMBED BACK TO MY ALT AND THANKED THE CTLRS FOR THEIR AGGRESSIVE TFC CALLOUTS. I DON'T THINK THE SMALL ACFT DID ANYTHING WRONG. AS HE CHANGED HDG HE DESCENDED TO THE APPROPRIATE SECTOR ALT. HIS ONLY PROBLEM WAS THAT HE DIDN'T SEE US. WITHOUT THE RADAR WARNINGS WE WOULD HAVE HAD A VERY EXCITING INCIDENT.

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.