Narrative:

We were cleared for the B/C approach into santa maria (smx). We had just reported camco intersection (DME) and were IMC when an small aircraft reported he had the airport in sight and was one mi east. The controller gave the small aircraft an immediate turn away from us. The small aircraft had entered the air traffic area without clearance while it was IFR. We never saw the small aircraft. When we descended through the cloud deck, tower advised small aircraft pilot to call tower.

Google
 

Original NASA ASRS Text

Title: CLOSE PROX COMMUTER SMA ENTERING AN IAP ILS BC APCH AND A GA SMA ENTERING THE ATA VFR UNANNOUNCED.

Narrative: WE WERE CLRED FOR THE B/C APCH INTO SANTA MARIA (SMX). WE HAD JUST RPTED CAMCO INTXN (DME) AND WERE IMC WHEN AN SMA RPTED HE HAD THE ARPT IN SIGHT AND WAS ONE MI E. THE CTLR GAVE THE SMA AN IMMEDIATE TURN AWAY FROM US. THE SMA HAD ENTERED THE ATA WITHOUT CLRNC WHILE IT WAS IFR. WE NEVER SAW THE SMA. WHEN WE DSNDED THROUGH THE CLOUD DECK, TWR ADVISED SMA PLT TO CALL TWR.

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.