Narrative:

Flying inbound from the east to land in hvn, contacted tower 10 mi out to instruction. Was told to call back on 4 mi, plan left traffic for runway 14. Called inbound 4 mi out, tower said to report entering left downwind for runway 14. Upon reaching airport traffic pattern I joined left downwind on the 45 degree entry for runway 14. Tower advised me I had traffic on right downwind for runway 20, touch and go. I stated I had no visual contact with reported traffic. At that time the aircraft passed approximately 100 ft under my aircraft flying in the opposite direction. After a near miss, I stated, 'unbelievable' on the tower frequency. Tower advised me it was 'see and avoid' on VFR. The other aircraft stated 'traffic no factor' after the fact of the near miss. I was cleared to land and did so immediately. Once on the ground I contacted the tower by phone to have him explain his perception of the incident. Tower manager stated it was VFR, 'see and avoid.' in my opinion an altitude request from both aircraft would have been extremely helpful when I stated no visual contact of the other aircraft, instead of saying 'see and avoid.' a request for one of us to do a 360 degree turn for spacing was another option.

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Original NASA ASRS Text

Title: NMAC BTWN TO SMA SEL ACFT IN A CTLED TFC PATTERN FOR 2 DIFFERENT RWYS AND OPPOSITE DIRECTION PATTERNS.

Narrative: FLYING INBOUND FROM THE E TO LAND IN HVN, CONTACTED TWR 10 MI OUT TO INSTRUCTION. WAS TOLD TO CALL BACK ON 4 MI, PLAN L TFC FOR RWY 14. CALLED INBOUND 4 MI OUT, TWR SAID TO RPT ENTERING L DOWNWIND FOR RWY 14. UPON REACHING ARPT TFC PATTERN I JOINED L DOWNWIND ON THE 45 DEG ENTRY FOR RWY 14. TWR ADVISED ME I HAD TFC ON R DOWNWIND FOR RWY 20, TOUCH AND GO. I STATED I HAD NO VISUAL CONTACT WITH RPTED TFC. AT THAT TIME THE ACFT PASSED APPROX 100 FT UNDER MY ACFT FLYING IN THE OPPOSITE DIRECTION. AFTER A NEAR MISS, I STATED, 'UNBELIEVABLE' ON THE TWR FREQ. TWR ADVISED ME IT WAS 'SEE AND AVOID' ON VFR. THE OTHER ACFT STATED 'TFC NO FACTOR' AFTER THE FACT OF THE NEAR MISS. I WAS CLRED TO LAND AND DID SO IMMEDIATELY. ONCE ON THE GND I CONTACTED THE TWR BY PHONE TO HAVE HIM EXPLAIN HIS PERCEPTION OF THE INCIDENT. TWR MGR STATED IT WAS VFR, 'SEE AND AVOID.' IN MY OPINION AN ALT REQUEST FROM BOTH ACFT WOULD HAVE BEEN EXTREMELY HELPFUL WHEN I STATED NO VISUAL CONTACT OF THE OTHER ACFT, INSTEAD OF SAYING 'SEE AND AVOID.' A REQUEST FOR ONE OF US TO DO A 360 DEG TURN FOR SPACING WAS ANOTHER OPTION.

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.