Narrative:

While holding at the day VOR on the 270 degree radial inbound, a target was observed on our TCASII at 10 O'clock and 5 mi (TCASII was in the 5 mi mode). Target was not called to our attention by ATC, target was showing plus 300 ft above our current holding altitude of 10000 ft (altimeter set to 29.67). Traffic continued to approach our position. When at our 2 mi range, my request to my copilot was to verify with dayton approach that traffic was approaching us at 10300 ft. The frequency at that moment was congested. Traffic now indicated plus 200 ft above our altitude. TCASII alerted 'traffic.' in not being able to verify our target I decided to take evasive action, a 60 degree right descending turn to 9500 ft. We told ATC of our deviation afterward and we were told traffic did exist at our position at 10300 ft. Later he had climbed to 10500 ft we were also told he was VFR and dayton approach was not talking to him at the time (the cloud tops were at 15000 ft and we were solid IMC). Later we were informed that our conflicting aircraft had picked up an IFR clearance and they were going to follow up with tracking this aircraft as of now. I don't know when I will hear from them. As of yet no actions have been taken, to my knowledge.

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Original NASA ASRS Text

Title: COMMUTER LTT HAS TCASII TARGET ON COLLISION COURSE. TAKES EVASIVE ACTION.

Narrative: WHILE HOLDING AT THE DAY VOR ON THE 270 DEG RADIAL INBOUND, A TARGET WAS OBSERVED ON OUR TCASII AT 10 O'CLOCK AND 5 MI (TCASII WAS IN THE 5 MI MODE). TARGET WAS NOT CALLED TO OUR ATTN BY ATC, TARGET WAS SHOWING PLUS 300 FT ABOVE OUR CURRENT HOLDING ALT OF 10000 FT (ALTIMETER SET TO 29.67). TFC CONTINUED TO APCH OUR POS. WHEN AT OUR 2 MI RANGE, MY REQUEST TO MY COPLT WAS TO VERIFY WITH DAYTON APCH THAT TFC WAS APCHING US AT 10300 FT. THE FREQ AT THAT MOMENT WAS CONGESTED. TFC NOW INDICATED PLUS 200 FT ABOVE OUR ALT. TCASII ALERTED 'TFC.' IN NOT BEING ABLE TO VERIFY OUR TARGET I DECIDED TO TAKE EVASIVE ACTION, A 60 DEG R DSNDING TURN TO 9500 FT. WE TOLD ATC OF OUR DEV AFTERWARD AND WE WERE TOLD TFC DID EXIST AT OUR POS AT 10300 FT. LATER HE HAD CLBED TO 10500 FT WE WERE ALSO TOLD HE WAS VFR AND DAYTON APCH WAS NOT TALKING TO HIM AT THE TIME (THE CLOUD TOPS WERE AT 15000 FT AND WE WERE SOLID IMC). LATER WE WERE INFORMED THAT OUR CONFLICTING ACFT HAD PICKED UP AN IFR CLRNC AND THEY WERE GOING TO FOLLOW UP WITH TRACKING THIS ACFT AS OF NOW. I DON'T KNOW WHEN I WILL HEAR FROM THEM. AS OF YET NO ACTIONS HAVE BEEN TAKEN, TO MY KNOWLEDGE.

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.