SMT PLT HAD AN NMAC WITH A PA28 IN PDT CLASS D AIRSPACE. THE ATCT LCL CTLR DID NOT ISSUE ANY TA'S.

Narrative

I WAS IFR FROM PDX-PDT. I WAS DSNDING INTO PDT AND CHINOOK APCH INFORMED ME THAT THERE WAS TFC ON THE ILS RWY 25 OUTSIDE FORIS MARKER BEACON AND I WAS #2 FOR THE ARPT. HE VECTORED ME 5 DEGS L FOR THE VISUAL RWY 11. WHEN I RPTED ARPT IN SIGHT; HE HANDED ME OFF TO TWR. AS I SWITCHED FREQS I HEARD SOMEONE CLRED TO TAXI TO PARKING AND ASSUMED (MISTAKENLY) THAT IT WAS THE ILS TFC. APCH CTL MADE NO MENTION OF EXPECTING TFC OUTBOUND ON THE MISSED APCH AND TWR DID NOT MENTION TFC TO ME EITHER. I HAD INITIALLY CALLED TWR 10 MI W OF PDT VOR AND WAS ASKED TO RPT ABEAM THE VORTAC FOR R BASE RWY 11. WHEN I WAS 2 NM NW OF THE VOR; I HEARD SOMEONE ASK FOR A FREQ CHANGE. ABOUT 10 SECONDS LATER OR LESS; A PIPER ARROW PASSED OPPOSITE DIRECTION. MAYBE 100 FT ABOVE ME AND 3 WING SPAN LENGTHS (ROUGHLY) OFF MY R WING. I HAD HAD NO WARNING FROM APCH OR TWR AND HAD NO TIME TO REACT. I RECOGNIZED THE OTHER AIRPLANE AND THE VOICE OF THE PLT. I CALLED HIM LATER AND HE SAID HE NEVER SAW ME EITHER. I SHOULD HAVE BEEN SCANNING A BIT MORE; BUT THERE WAS NO RELATIVE MOTION TO CATCH MY EYE. I THINK IT COULD HAVE BEEN AVOIDED IF EITHER CHINOOK APCH OR TWR HAD WARNED ME TO WATCH FOR TFC OUTBOUND ON MISSED APCH.