AN MLG CREW ON APCH TO GEG; MADE A GAR; REALIZING THEY WERE LINED UP ON THE WRONG RWY.

Narrative

WHILE ON APCH TO SPOKANE ARPT; ACFT WAS CLRED DIRECT PHORT OM (ILS RWY 21); WHILE TRYING TO ACQUIRE THE ARPT FOR A VISUAL APCH. AT APPROX 5-10 NM FROM PHORT; ACFT WAS GIVEN A 260 DEG HDG TOWARDS THE ARPT WHICH WAS STILL NOT IN SIGHT DUE TO A SCATTERED CLOUD DECK BLOCKING THE RWY. THIS HDG APPEARED TO TAKE US RIGHT AT THE APCH END OF THE RWY. WHILE ON THE HDG; A RWY APPEARED AND A HURRIED EFFORT WAS MADE TO GET IN POS TO LAND. AFTER GETTING GEAR AND FLAPS DOWN AND COMPLETELY PAST ANY CLOUDS; WE HAD INADVERTENTLY LINED UP FOR RWY 25 VERSUS RWY 21. WE ELECTED TO EXECUTE A GAR AND REQUESTED A FULL ILS TO RWY 21. THIS INCIDENT COULD HAVE BEEN AVOIDED WITH CLRER COM (DIRECTIONS AND INTENTIONS) BTWN THE PLTS AND THE CTLRS. SUPPLEMENTAL INFO FROM ACN 535486: THE CTLR THEN GAVE US A L TURN TO APPROX 260 DEG HDG WHICH WOULD TAKE US RIGHT TO THE END OF RWY 21. WHEN I ASKED WHY; THE CTLR SAID IT WAS TO PUT US ON A 'CLOSE BASE.' SINCE THIS WOULD MAKE IT IMPOSSIBLE TO COMPLETE A VISUAL TO RWY 21 FROM THIS POS; I WASN'T SURE WHAT THE PLAN WAS. WHEN WE COMPLETED THE TURN; WE CLRED THE CLOUD BAND AND WERE ALMOST LINED UP ON RWY 25. I ASSUMED THAT THE VECTOR WAS FOR RWY 25 AND CALLED THE ARPT IN SIGHT. AT THAT POINT; I THOUGHT THE CTLR CLRED US FOR A VISUAL APCH. WHEN I ASKED ABOUT CONTACTING THE TWR; ATC ADVISED WE WERE LINED UP ON RWY 25; WHICH I THEN REALIZED WAS NOT THE PLAN. WE THEN WENT AROUND AND WAS VECTORED BACK TO RWY 21.