Narrative:

On initial climb, VFR traffic items appeared on TCASII. While no RA was indicated, I chose to climb through my assigned altitude of 2000 ft. I intended to level at 2300 ft, but actually stopped the climb at 2400 ft and immediately began a descent as I now had visual contact with the first target. Simultaneously I was given climb instructions to a higher altitude.

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Original NASA ASRS Text

Title: AN ATP RATED PLT FLYING A CPR TWIN OBSERVED VFR TARGET ON HIS TCASII DISPLAY AND CLBS ABOVE HIS ASSIGNED ALT.

Narrative: ON INITIAL CLB, VFR TFC ITEMS APPEARED ON TCASII. WHILE NO RA WAS INDICATED, I CHOSE TO CLB THROUGH MY ASSIGNED ALT OF 2000 FT. I INTENDED TO LEVEL AT 2300 FT, BUT ACTUALLY STOPPED THE CLB AT 2400 FT AND IMMEDIATELY BEGAN A DSCNT AS I NOW HAD VISUAL CONTACT WITH THE FIRST TARGET. SIMULTANEOUSLY I WAS GIVEN CLB INSTRUCTIONS TO A HIGHER ALT.

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.