Narrative:

At bar harbor airport, a non twred airport, in VFR conditions, I experienced an near midair collision with a citation jet on a straight-in approach. I was flying a C172 and I was on a l-hand pattern. After announcing to all traffic on CTAF that I was turning base I completed the turn to base. My passenger and I heard the citation call his position as of 10 mi northeast of the airport, but we did not hear the word 'citation.' the citation did not announce its position again until the OM, which is 5 mi from the end of the runway. The citation did not give its distance from the runway, just 'citation inbound for runway 22.' since a citation jet approachs at very high speed, it covers a lot of distance between reporting points in very little time. Since I had just turned left base, I knew that a collision was imminent. This is because I know where the OM is located. Not all VFR pilots would have known where the OM is located. I immediately turned right and announced to all traffic that I was extending the downwind leg. The citation passed safely and landed.

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Original NASA ASRS Text

Title: C172 PLT TOOK EVASIVE ACTION AND TURNED AWAY FROM FINAL APCH TO A NON TWRED ARPT TO AVOID A CESSNA CITATION JET ON A STRAIGHT-IN APCH.

Narrative: AT BAR HARBOR ARPT, A NON TWRED ARPT, IN VFR CONDITIONS, I EXPERIENCED AN NMAC WITH A CITATION JET ON A STRAIGHT-IN APCH. I WAS FLYING A C172 AND I WAS ON A L-HAND PATTERN. AFTER ANNOUNCING TO ALL TFC ON CTAF THAT I WAS TURNING BASE I COMPLETED THE TURN TO BASE. MY PAX AND I HEARD THE CITATION CALL HIS POS AS OF 10 MI NE OF THE ARPT, BUT WE DID NOT HEAR THE WORD 'CITATION.' THE CITATION DID NOT ANNOUNCE ITS POS AGAIN UNTIL THE OM, WHICH IS 5 MI FROM THE END OF THE RWY. THE CITATION DID NOT GIVE ITS DISTANCE FROM THE RWY, JUST 'CITATION INBOUND FOR RWY 22.' SINCE A CITATION JET APCHS AT VERY HIGH SPD, IT COVERS A LOT OF DISTANCE BTWN RPTING POINTS IN VERY LITTLE TIME. SINCE I HAD JUST TURNED L BASE, I KNEW THAT A COLLISION WAS IMMINENT. THIS IS BECAUSE I KNOW WHERE THE OM IS LOCATED. NOT ALL VFR PLTS WOULD HAVE KNOWN WHERE THE OM IS LOCATED. I IMMEDIATELY TURNED R AND ANNOUNCED TO ALL TFC THAT I WAS EXTENDING THE DOWNWIND LEG. THE CITATION PASSED SAFELY AND LANDED.

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.