Narrative:

I called new haven tower when I was inbound from the east at 8 mi as indicated on my DME. I was asked to enter a left base for runway 20 and report a 2 mi left base. I had only flown out of this airport once before and was relatively unfamiliar with it so I was keeping a close watch on the ground in an attempt to set myself up for a perfect base leg. I was also scanning for traffic but found some difficulty doing so because it was dusk. At 2.8 DME I was just about to report my 2 mi left base when I saw a regional jet to my left (the south) at my same altitude (1000 ft) coming straight at me. The tower controller then asked my distance (2.8 DME) but before I could answer he instructed me to turn right. The aircraft climbed and turned to the right. I later learned that I had set off his TCASII system during discussion over the radio on the ground. I had not yet reached a 2 mi base and unfortunately both aircraft were on intersecting paths. The tower never called the traffic out to me which would have helped. This problem could have been avoided if the tower controller had radar. Another way this problem could have been avoided is if the other aircraft and I had seen one another (better scanning).

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Original NASA ASRS Text

Title: SMA ACFT ARRIVING AT NON RADAR ARPT HAD NMAC WITH DEPARTING ACR ACFT SETTING OFF THE ACR'S TCASII. CTLR INTERVENED TO TURN RPTR AS ACR ACFT TOOK EVASIVE ACTION.

Narrative: I CALLED NEW HAVEN TWR WHEN I WAS INBOUND FROM THE E AT 8 MI AS INDICATED ON MY DME. I WAS ASKED TO ENTER A L BASE FOR RWY 20 AND RPT A 2 MI L BASE. I HAD ONLY FLOWN OUT OF THIS ARPT ONCE BEFORE AND WAS RELATIVELY UNFAMILIAR WITH IT SO I WAS KEEPING A CLOSE WATCH ON THE GND IN AN ATTEMPT TO SET MYSELF UP FOR A PERFECT BASE LEG. I WAS ALSO SCANNING FOR TFC BUT FOUND SOME DIFFICULTY DOING SO BECAUSE IT WAS DUSK. AT 2.8 DME I WAS JUST ABOUT TO RPT MY 2 MI L BASE WHEN I SAW A REGIONAL JET TO MY L (THE S) AT MY SAME ALT (1000 FT) COMING STRAIGHT AT ME. THE TWR CTLR THEN ASKED MY DISTANCE (2.8 DME) BUT BEFORE I COULD ANSWER HE INSTRUCTED ME TO TURN R. THE ACFT CLBED AND TURNED TO THE R. I LATER LEARNED THAT I HAD SET OFF HIS TCASII SYS DURING DISCUSSION OVER THE RADIO ON THE GND. I HAD NOT YET REACHED A 2 MI BASE AND UNFORTUNATELY BOTH ACFT WERE ON INTERSECTING PATHS. THE TWR NEVER CALLED THE TFC OUT TO ME WHICH WOULD HAVE HELPED. THIS PROB COULD HAVE BEEN AVOIDED IF THE TWR CTLR HAD RADAR. ANOTHER WAY THIS PROB COULD HAVE BEEN AVOIDED IS IF THE OTHER ACFT AND I HAD SEEN ONE ANOTHER (BETTER SCANNING).

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.