Narrative:

Aircraft was on a 090 heading, under radar control of colorado springs departure control. Our aircraft has TCASII and we had noticed traffic ahead whose altitude we would pass through. ATC gave us a 080 heading and advised that the traffic should pass to our right. The TCASII advised traffic! I looked up to see an light transport crossing our nose at approximately the same altitude. I initiated a rapid climb which caused the passenger to cry out in the back 'whoa.' as I initiated the pull up the TCASII advised to increase the climb rate by advising 'monitor vertical speed' and showing a 2500 FPM rate of climb. After we were clear of conflict departure announced that she had just noticed that the traffic had turned across our nose, this call would have been a little late had one of us not had our eyes out of the cockpit and had we not had TCASII. I find that increasingly in busy terminal areas with a lot of VFR traffic we get more and more traffic advisories that are backed up by visual sightings. I wonder if ATC knows that we have TCASII and is therefore leaving it up to us to avoid VFR traffic that is in conflict. I have had 2 similar occurrences at peachtree de kalb airport outside atlanta, but this is the closest we have come while under radar control.

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Original NASA ASRS Text

Title: CORP LTT HAS NMAC WITH SECOND LTT. CTLR HAVE GIVEN VECTOR TO SEPARATE.

Narrative: ACFT WAS ON A 090 HDG, UNDER RADAR CTL OF COLORADO SPRINGS DEP CTL. OUR ACFT HAS TCASII AND WE HAD NOTICED TFC AHEAD WHOSE ALT WE WOULD PASS THROUGH. ATC GAVE US A 080 HDG AND ADVISED THAT THE TFC SHOULD PASS TO OUR R. THE TCASII ADVISED TFC! I LOOKED UP TO SEE AN LTT XING OUR NOSE AT APPROX THE SAME ALT. I INITIATED A RAPID CLB WHICH CAUSED THE PAX TO CRY OUT IN THE BACK 'WHOA.' AS I INITIATED THE PULL UP THE TCASII ADVISED TO INCREASE THE CLB RATE BY ADVISING 'MONITOR VERT SPD' AND SHOWING A 2500 FPM RATE OF CLB. AFTER WE WERE CLR OF CONFLICT DEP ANNOUNCED THAT SHE HAD JUST NOTICED THAT THE TFC HAD TURNED ACROSS OUR NOSE, THIS CALL WOULD HAVE BEEN A LITTLE LATE HAD ONE OF US NOT HAD OUR EYES OUT OF THE COCKPIT AND HAD WE NOT HAD TCASII. I FIND THAT INCREASINGLY IN BUSY TERMINAL AREAS WITH A LOT OF VFR TFC WE GET MORE AND MORE TFC ADVISORIES THAT ARE BACKED UP BY VISUAL SIGHTINGS. I WONDER IF ATC KNOWS THAT WE HAVE TCASII AND IS THEREFORE LEAVING IT UP TO US TO AVOID VFR TFC THAT IS IN CONFLICT. I HAVE HAD 2 SIMILAR OCCURRENCES AT PEACHTREE DE KALB ARPT OUTSIDE ATLANTA, BUT THIS IS THE CLOSEST WE HAVE COME WHILE UNDER RADAR CTL.

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.