Narrative:

VFR night. Briefed approach to lax CIVET5 runway 25L prior to top of descent. Was cleared to descend via the civet. Just past krain descending through 10K approach noted us on the runway 25L localizer and asked us when we were going to intercept runway 24R. We replied that we were assigned runway 25L. We asked controller to confirm runway assignment but controller just gave us a 10 degree right turn for runway 24R localizer which we intercepted and landed normally. Debriefing with the captain on the ground we both remarked that although we initially thought we were cleared to descend via the civet for runway 25L that it was possible we were only cleared to descend via the civet and the controller left out runway 24R. While it's possible the controller included runway 24R and we just missed it; we both felt that was unlikely due to the extra taxi delay that assignment incurs for us which we felt would get out attention. There didn't appear to be any traffic separation issue; just prior to switching our runway approach had pointed out traffic that we had in sight 5 miles ahead.

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Original NASA ASRS Text

Title: B757 CREW INTERCEPTS RWY 25L LOCALIZER AS THEY BELIEVE THEY WERE CLRED; SCT CTLR ISSUES VECTOR TO INTERCEPT THE RWY 24R LOCALIZER AS HE BELIEVES THEY WERE CLRED.

Narrative: VFR NIGHT. BRIEFED APPROACH TO LAX CIVET5 RWY 25L PRIOR TO TOP OF DESCENT. WAS CLEARED TO DESCEND VIA THE CIVET. JUST PAST KRAIN DESCENDING THROUGH 10K APPROACH NOTED US ON THE RWY 25L LOCALIZER AND ASKED US WHEN WE WERE GOING TO INTERCEPT RWY 24R. WE REPLIED THAT WE WERE ASSIGNED RWY 25L. WE ASKED CONTROLLER TO CONFIRM RUNWAY ASSIGNMENT BUT CONTROLLER JUST GAVE US A 10 DEGREE RIGHT TURN FOR RWY 24R LOC WHICH WE INTERCEPTED AND LANDED NORMALLY. DEBRIEFING WITH THE CAPTAIN ON THE GROUND WE BOTH REMARKED THAT ALTHOUGH WE INITIALLY THOUGHT WE WERE CLEARED TO DESCEND VIA THE CIVET FOR RWY 25L THAT IT WAS POSSIBLE WE WERE ONLY CLEARED TO DESCEND VIA THE CIVET AND THE CONTROLLER LEFT OUT RWY 24R. WHILE IT'S POSSIBLE THE CONTROLLER INCLUDED RWY 24R AND WE JUST MISSED IT; WE BOTH FELT THAT WAS UNLIKELY DUE TO THE EXTRA TAXI DELAY THAT ASSIGNMENT INCURS FOR US WHICH WE FELT WOULD GET OUT ATTENTION. THERE DIDN'T APPEAR TO BE ANY TRAFFIC SEPARATION ISSUE; JUST PRIOR TO SWITCHING OUR RUNWAY APPROACH HAD POINTED OUT TRAFFIC THAT WE HAD IN SIGHT 5 MILES AHEAD.

Data retrieved from NASA's ASRS site as of January 2009 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.