Narrative:

Light plane with no communication to ord tower heading northeast across approach path from right to left. He was reported at 2600' and 2 mi at 2:30. We saw him, we were at 2600-2700' descending. At 2300' I started missed approach simultaneously with tower issuing us a missed approach (go around). We passed directly over the light aircraft (I figured 200'--approach said mode C showed 100'). Approach control and I agree that the missed approach was initiated at 200' vertical and 1 mi distance.

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Original NASA ASRS Text

Title: NMAC WITH SMA ACFT IN THE TCA WITHOUT CLRNC.

Narrative: LIGHT PLANE WITH NO COM TO ORD TWR HDG NE ACROSS APCH PATH FROM RIGHT TO LEFT. HE WAS RPTED AT 2600' AND 2 MI AT 2:30. WE SAW HIM, WE WERE AT 2600-2700' DSNDING. AT 2300' I STARTED MISSED APCH SIMULTANEOUSLY WITH TWR ISSUING US A MISSED APCH (GO AROUND). WE PASSED DIRECTLY OVER THE LIGHT ACFT (I FIGURED 200'--APCH SAID MODE C SHOWED 100'). APCH CTL AND I AGREE THAT THE MISSED APCH WAS INITIATED AT 200' VERT AND 1 MI DISTANCE.

Data retrieved from NASA's ASRS site as of August 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.