Narrative:

I departed south st paul airport (D97-fleming field) and contacted st paul downtown airport (stp-holman field) tower requesting to do 2 touch and go lndgs. I was cleared to do so using right traffic for runway 32. After the second landing, I asked to depart the pattern to the east. I was cleared as requested and flew on a 90 degree heading for approximately 4-5 NM, and then headed southwest to return to fleming field. Approximately 2 NM northeast of fleming field and at 2000 ft MSL, I noticed a twin engine aircraft approximately 2 NM away at my 10 O'clock position. At that time the other aircraft was above my altitude, but it was apparent that he was descending on the glidepath to runway 32 at holman field. I descended to 1800 ft MSL, passing underneath and ahead of the other aircraft by what I would estimate as 500 ft. Immediately after we crossed paths, the pilot of the twin reported seeing us to the holman field tower. The tower operator was unaware of our position and did not realize that there was a potential traffic conflict. I talked to the tower operator after landing and she said that she was unaware that I was returning to fleming field. In retrospect, although I was outside of controled airspace, had I informed the tower operator of my intentions to return to fleming field, she would have been able to advise both the twin engine aircraft and myself of the potential traffic conflict.

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Original NASA ASRS Text

Title: T-6 HAS NMAC WITH TWIN.

Narrative: I DEPARTED SOUTH ST PAUL ARPT (D97-FLEMING FIELD) AND CONTACTED ST PAUL DOWNTOWN ARPT (STP-HOLMAN FIELD) TWR REQUESTING TO DO 2 TOUCH AND GO LNDGS. I WAS CLRED TO DO SO USING R TFC FOR RWY 32. AFTER THE SECOND LNDG, I ASKED TO DEPART THE PATTERN TO THE E. I WAS CLRED AS REQUESTED AND FLEW ON A 90 DEG HDG FOR APPROX 4-5 NM, AND THEN HEADED SW TO RETURN TO FLEMING FIELD. APPROX 2 NM NE OF FLEMING FIELD AND AT 2000 FT MSL, I NOTICED A TWIN ENG ACFT APPROX 2 NM AWAY AT MY 10 O'CLOCK POS. AT THAT TIME THE OTHER ACFT WAS ABOVE MY ALT, BUT IT WAS APPARENT THAT HE WAS DSNDING ON THE GLIDEPATH TO RWY 32 AT HOLMAN FIELD. I DSNDED TO 1800 FT MSL, PASSING UNDERNEATH AND AHEAD OF THE OTHER ACFT BY WHAT I WOULD ESTIMATE AS 500 FT. IMMEDIATELY AFTER WE CROSSED PATHS, THE PLT OF THE TWIN RPTED SEEING US TO THE HOLMAN FIELD TWR. THE TWR OPERATOR WAS UNAWARE OF OUR POS AND DID NOT REALIZE THAT THERE WAS A POTENTIAL TFC CONFLICT. I TALKED TO THE TWR OPERATOR AFTER LNDG AND SHE SAID THAT SHE WAS UNAWARE THAT I WAS RETURNING TO FLEMING FIELD. IN RETROSPECT, ALTHOUGH I WAS OUTSIDE OF CTLED AIRSPACE, HAD I INFORMED THE TWR OPERATOR OF MY INTENTIONS TO RETURN TO FLEMING FIELD, SHE WOULD HAVE BEEN ABLE TO ADVISE BOTH THE TWIN ENG ACFT AND MYSELF OF THE POTENTIAL TFC CONFLICT.

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.