Narrative:

On downwind, we were level at 4000 ft MSL for runway 32. Noticed aircraft 12 O'clock position, 2 1/2 mi, 600 ft below us. We were on 140 degree heading when aircraft got 300 ft below. We turned to 180 degree heading. Aircraft in sight, as we turned, at our 11 O'clock position. Had visual on aircraft at the 11 O'clock position and same altitude. Continued flight uneventfully, and landed at srq. Supplemental information from acn 548020: I was misassigned a heading and altitude of 3000 ft. I had set my altimeter per the ATIS at 29.40. I was level at 3000 ft when controller asked my altitude and told me he had me at 4000 ft. I asked for barometer setting, and was told 30.40. A 737 had evaded due to TCASII. I descended and called tampa approach when I landed. I should have noticed the altimeter and field elevation differed by 1000 ft, but I am used to flying at higher elevations.

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Original NASA ASRS Text

Title: AN ARRIVING B737 HAS A CONFLICT WITH AN OPPOSITE DIRECTION CIRRUS SR22 CLBING TO SAME ALT OF 4000 FT, 5 NM NW OF SRQ, FL.

Narrative: ON DOWNWIND, WE WERE LEVEL AT 4000 FT MSL FOR RWY 32. NOTICED ACFT 12 O'CLOCK POS, 2 1/2 MI, 600 FT BELOW US. WE WERE ON 140 DEG HDG WHEN ACFT GOT 300 FT BELOW. WE TURNED TO 180 DEG HDG. ACFT IN SIGHT, AS WE TURNED, AT OUR 11 O'CLOCK POS. HAD VISUAL ON ACFT AT THE 11 O'CLOCK POS AND SAME ALT. CONTINUED FLT UNEVENTFULLY, AND LANDED AT SRQ. SUPPLEMENTAL INFO FROM ACN 548020: I WAS MISASSIGNED A HDG AND ALT OF 3000 FT. I HAD SET MY ALTIMETER PER THE ATIS AT 29.40. I WAS LEVEL AT 3000 FT WHEN CTLR ASKED MY ALT AND TOLD ME HE HAD ME AT 4000 FT. I ASKED FOR BAROMETER SETTING, AND WAS TOLD 30.40. A 737 HAD EVADED DUE TO TCASII. I DSNDED AND CALLED TAMPA APCH WHEN I LANDED. I SHOULD HAVE NOTICED THE ALTIMETER AND FIELD ELEVATION DIFFERED BY 1000 FT, BUT I AM USED TO FLYING AT HIGHER ELEVATIONS.

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.