Narrative:

On feb/thu/1989 at XA40 on the descent into seattle on the 158 degree radial, we had a near miss with a yellow and white small aircraft. We had been given a clearance to cross 30 south of seattle at 10000'. Out of 10200 I saw the other aircraft at 12 O'clock and less than 1/2 mi. After taking evasive action I asked seattle center if they showed any other aircraft in our area. The controller, after a short pause, said yes. I proceeded to tell him the distance we passed and color. They tracked the aircraft and had it identified before we landed in seattle. At the time we were in IFR conditions.

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Original NASA ASRS Text

Title: NMAC BETWEEN ACR-LTT DESCENDING AND GA-SMA.

Narrative: ON FEB/THU/1989 AT XA40 ON THE DSCNT INTO SEATTLE ON THE 158 DEG RADIAL, WE HAD A NEAR MISS WITH A YELLOW AND WHITE SMA. WE HAD BEEN GIVEN A CLRNC TO CROSS 30 S OF SEATTLE AT 10000'. OUT OF 10200 I SAW THE OTHER ACFT AT 12 O'CLOCK AND LESS THAN 1/2 MI. AFTER TAKING EVASIVE ACTION I ASKED SEATTLE CENTER IF THEY SHOWED ANY OTHER ACFT IN OUR AREA. THE CTLR, AFTER A SHORT PAUSE, SAID YES. I PROCEEDED TO TELL HIM THE DISTANCE WE PASSED AND COLOR. THEY TRACKED THE ACFT AND HAD IT IDENTIFIED BEFORE WE LANDED IN SEATTLE. AT THE TIME WE WERE IN IFR CONDITIONS.

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.