Narrative:

Aircraft X was on a radar vector for ILS runway 28R approach at pdx. I called traffic for aircraft X on a primary target 1 O'clock, 4 mi, opposite direction, no transponder. Aircraft X then reported the target just went by 50 ft off his right side. We need 'B' airspace before a midair occurs.

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Original NASA ASRS Text

Title: A PDX APCH CTLR MISJUDGED THE CLOSENESS OF TFC WHICH HE CONTRIBUTES TO THE NEED FOR A CLASS B AIRSPACE.

Narrative: ACFT X WAS ON A RADAR VECTOR FOR ILS RWY 28R APCH AT PDX. I CALLED TFC FOR ACFT X ON A PRIMARY TARGET 1 O'CLOCK, 4 MI, OPPOSITE DIRECTION, NO XPONDER. ACFT X THEN RPTED THE TARGET JUST WENT BY 50 FT OFF HIS R SIDE. WE NEED 'B' AIRSPACE BEFORE A MIDAIR OCCURS.

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.