Narrative:

Approaching tpa airport on an IFR flight plan and the first officer flying, assigned 6000 ft and my attention diverted looking for TCASII traffic, first officer descended through assigned altitude. Tpa controller brought it to my attention at 4800 ft and we climbed back to assigned altitude. Busy airspace and high performance aircraft require constant vigilance from both pilots.

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Original NASA ASRS Text

Title: THE CAPT OF A CITATION WAS DISTRACTED BY TCASII TFC AS FO DSNDED THROUGH ASSIGNED ALT.

Narrative: APCHING TPA ARPT ON AN IFR FLT PLAN AND THE FO FLYING, ASSIGNED 6000 FT AND MY ATTN DIVERTED LOOKING FOR TCASII TFC, FO DSNDED THROUGH ASSIGNED ALT. TPA CTLR BROUGHT IT TO MY ATTN AT 4800 FT AND WE CLBED BACK TO ASSIGNED ALT. BUSY AIRSPACE AND HIGH PERFORMANCE ACFT REQUIRE CONSTANT VIGILANCE FROM BOTH PLTS.

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.