Narrative:

While being controled and vectored by cvg approach control, we were given a vector heading to 250 degrees and descent to 8000 ft. At leveloff at 8000 ft, the TCASII first gave us a TA for a conflict approximately 1 1/2 mi ahead and 400 ft below us. As soon as I looked out for the traffic we received an RA 'monitor vertical speed,' and shortly thereafter a 'climb, climb.' I disconnected the autoplt and rotated the aircraft toward the green arc, turned right, and tried to visually find the target aircraft. I believe at the same time approach control called us and told us to climb and turn right also, but with the autoplt disc warning, altitude reminder warnings going off, and calling out that I had visual on the conflict aircraft, I am not positive what approach control told us to do. My best estimate on missing the civilian C310 was 500 ft horizontal and 300-400 ft vertical. I climbed to about 8800 ft before clear of conflict sounded and then descended back to 8000 ft assigned altitude. Approach control stated that the aircraft in conflict was talking to nobody. We questioned why we were not informed of this aircraft earlier and given different descent and vector headings. This small aircraft was in class B airspace flying right down the cvg approach vector pathway. I believe he was weaving his way around WX to stay VFR and got over in the class B airspace. This situation was dangerous!

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Original NASA ASRS Text

Title: ACR IN CLASS B AIRSPACE ENCOUNTERS UNCTLED NORDO LIGHT TWIN. SIMULTANEOUS TCASII AND ATC WARNING RESULTED IN TIMELY AVOIDANCE.

Narrative: WHILE BEING CTLED AND VECTORED BY CVG APCH CTL, WE WERE GIVEN A VECTOR HDG TO 250 DEGS AND DSCNT TO 8000 FT. AT LEVELOFF AT 8000 FT, THE TCASII FIRST GAVE US A TA FOR A CONFLICT APPROX 1 1/2 MI AHEAD AND 400 FT BELOW US. AS SOON AS I LOOKED OUT FOR THE TFC WE RECEIVED AN RA 'MONITOR VERT SPD,' AND SHORTLY THEREAFTER A 'CLB, CLB.' I DISCONNECTED THE AUTOPLT AND ROTATED THE ACFT TOWARD THE GREEN ARC, TURNED R, AND TRIED TO VISUALLY FIND THE TARGET ACFT. I BELIEVE AT THE SAME TIME APCH CTL CALLED US AND TOLD US TO CLB AND TURN R ALSO, BUT WITH THE AUTOPLT DISC WARNING, ALT REMINDER WARNINGS GOING OFF, AND CALLING OUT THAT I HAD VISUAL ON THE CONFLICT ACFT, I AM NOT POSITIVE WHAT APCH CTL TOLD US TO DO. MY BEST ESTIMATE ON MISSING THE CIVILIAN C310 WAS 500 FT HORIZ AND 300-400 FT VERT. I CLBED TO ABOUT 8800 FT BEFORE CLR OF CONFLICT SOUNDED AND THEN DSNDED BACK TO 8000 FT ASSIGNED ALT. APCH CTL STATED THAT THE ACFT IN CONFLICT WAS TALKING TO NOBODY. WE QUESTIONED WHY WE WERE NOT INFORMED OF THIS ACFT EARLIER AND GIVEN DIFFERENT DSCNT AND VECTOR HDGS. THIS SMALL ACFT WAS IN CLASS B AIRSPACE FLYING RIGHT DOWN THE CVG APCH VECTOR PATHWAY. I BELIEVE HE WAS WEAVING HIS WAY AROUND WX TO STAY VFR AND GOT OVER IN THE CLASS B AIRSPACE. THIS SIT WAS DANGEROUS!

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.