Narrative:

Climbing out of mdt, was leveled off at 13000 ft, advised of VFR traffic 10-11 O'clock 20 mi at 17500. Was then given clearance to climb to FL230. I observed VFR traffic on TCASII, appeared to me we were on possible collision course. I had my copilot level off at 16500. A few seconds later ATC asked our altitude (with concern in his voice). I said '16500 and leveled off, and that I had the VFR traffic on my TCASII'. Moments later the TCASII called out 'traffic'. VFR aircraft passed over us, never saw him visually. We then climbed to FL230. ATC should never have cleared us to FL230 or should have put us on a heading to avoid the traffic. Without the TCAS I think we would have had either a near miss or worse yet, a collision.

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Original NASA ASRS Text

Title: ACR MLG CLBING TO FL230 WAS GIVEN A TA OF VFR TFC AT 17500. TCASII ALSO WAS TRACKING THE TFC. FLC LEVELED AT 16500 UNTIL THE TFC WAS CLR.

Narrative: CLBING OUT OF MDT, WAS LEVELED OFF AT 13000 FT, ADVISED OF VFR TFC 10-11 O'CLOCK 20 MI AT 17500. WAS THEN GIVEN CLRNC TO CLB TO FL230. I OBSERVED VFR TFC ON TCASII, APPEARED TO ME WE WERE ON POSSIBLE COLLISION COURSE. I HAD MY COPLT LEVEL OFF AT 16500. A FEW SECONDS LATER ATC ASKED OUR ALT (WITH CONCERN IN HIS VOICE). I SAID '16500 AND LEVELED OFF, AND THAT I HAD THE VFR TFC ON MY TCASII'. MOMENTS LATER THE TCASII CALLED OUT 'TFC'. VFR ACFT PASSED OVER US, NEVER SAW HIM VISUALLY. WE THEN CLBED TO FL230. ATC SHOULD NEVER HAVE CLRED US TO FL230 OR SHOULD HAVE PUT US ON A HDG TO AVOID THE TFC. WITHOUT THE TCAS I THINK WE WOULD HAVE HAD EITHER A NEAR MISS OR WORSE YET, A COLLISION.

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.