Narrative:

While proceeding from sburg to hadji on the GPS-D airport to hayden/yampa valley in IMC, a flight called 'call sign abc' on a VFR climb, in contact with ZDV on frequency 134.5, turned toward our aircraft and passed in close proximity to the right side of our aircraft, going in the opposite direction, causing a TCASII RA that our PF responded to. ZDV was notified of the RA.

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Original NASA ASRS Text

Title: BA46 CREW HAD A TCASII RA WITH AN UNIDENTED ACFT WHILE IN IMC. THE INTRUDER WAS FLYING WITH A VFR FLT PLAN.

Narrative: WHILE PROCEEDING FROM SBURG TO HADJI ON THE GPS-D ARPT TO HAYDEN/YAMPA VALLEY IN IMC, A FLT CALLED 'CALL SIGN ABC' ON A VFR CLB, IN CONTACT WITH ZDV ON FREQ 134.5, TURNED TOWARD OUR ACFT AND PASSED IN CLOSE PROX TO THE R SIDE OF OUR ACFT, GOING IN THE OPPOSITE DIRECTION, CAUSING A TCASII RA THAT OUR PF RESPONDED TO. ZDV WAS NOTIFIED OF THE RA.

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.