Narrative:

I was on an IFR flight to ugn. Chicago center had handed me to the tower at ugn. I was cleared for the visual approach to runway 5; directed to report midfield left downwind for runway 5. My TCAS alerted me to traffic; both audible and visual; and I then saw a single engine out the right side; approximately 300 ft away at my altitude. There was no warning of the traffic. I did report that I had observed traffic; but did not report a near miss to the tower. I reported the midfield position and was cleared to land. There was no further incident. On the ground I played back several times the tower transmissions to listen for advisory I might have missed; but there were none given.

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Original NASA ASRS Text

Title: An pilot reported a near miss at 2;000 FT while in the UGN traffic pattern with no traffic alert from ATC.

Narrative: I was on an IFR flight to UGN. Chicago Center had handed me to the Tower at UGN. I was cleared for the visual approach to Runway 5; directed to report midfield left downwind for Runway 5. My TCAS alerted me to traffic; both audible and visual; and I then saw a single engine out the right side; approximately 300 FT away at my altitude. There was no warning of the traffic. I did report that I had observed traffic; but did not report a near miss to the Tower. I reported the midfield position and was cleared to land. There was no further incident. On the ground I played back several times the Tower transmissions to listen for advisory I might have missed; but there were none given.

Data retrieved from NASA's ASRS site as of July 2013 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.