Narrative:

Upon departing smo VOR on a heading of 070 degrees in a descent to 6000' our aircraft was cleared for a visibility approach to runway 24L at lax, to descend to 2000' and to keep another aircraft in sight. At this point we were 11 NM from the lax VOR. Approach control had originally cleared us to 24R. We were advised that the medium large transport was going to runway 24R. This compelled us to stay visibility with him and descend below him to line up on his left side (since he was cleared to 24R and we were cleared to 24L). After passing under him it was observed that we were lined up on the south complex and we concluded that the approach controller had mistakenly said 24R when 25R was intended for the medium large transport jet. We were then switched to tower frequency and advised them that we were correcting back to the right and runway 24L. An uneventful landing was accomplished. If we had continued as originally cleared for an approach to 24R, it would have been impossible to maintain visibility contact with the air carrier flight since we would have been banked steeply to the right. The cause of this situation was the congested, chaotic and confused environment of the lax approach area. There were too many 'plan for...' instructions given which were changed. Our runway was changed just as we were turning on the base leg. Note: in order to increase the vertical sep from the other air carrier flight, we descended and delayed our turn toward lax. The descent resulted in increased airspeed and caused a wider radius of turn exacerbating the overshoot. Our primary focus was maintaining a safe sep from the other aircraft.

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Original NASA ASRS Text

Title: ACR WDB ON A VISUAL APCH IS ASKED TO KEEP ANOTHER ACR MLG IN SIGHT FOR THE APCH. IN DOING SO THE WDB CREATES A POTENTIAL CONFLICT AND A HEADING TRACK DEVIATION AS HE OVERSHOOTS THE HEADING AND ENDS UP LINED UP WITH A WRONG RWY APCH.

Narrative: UPON DEPARTING SMO VOR ON A HDG OF 070 DEGS IN A DSNT TO 6000' OUR ACFT WAS CLRED FOR A VIS APCH TO RWY 24L AT LAX, TO DSND TO 2000' AND TO KEEP ANOTHER ACFT IN SIGHT. AT THIS POINT WE WERE 11 NM FROM THE LAX VOR. APCH CTL HAD ORIGINALLY CLRED US TO 24R. WE WERE ADVISED THAT THE MLG WAS GOING TO RWY 24R. THIS COMPELLED US TO STAY VIS WITH HIM AND DSND BELOW HIM TO LINE UP ON HIS LEFT SIDE (SINCE HE WAS CLRED TO 24R AND WE WERE CLRED TO 24L). AFTER PASSING UNDER HIM IT WAS OBSERVED THAT WE WERE LINED UP ON THE S COMPLEX AND WE CONCLUDED THAT THE APCH CTLR HAD MISTAKENLY SAID 24R WHEN 25R WAS INTENDED FOR THE MLG JET. WE WERE THEN SWITCHED TO TWR FREQ AND ADVISED THEM THAT WE WERE CORRECTING BACK TO THE RIGHT AND RWY 24L. AN UNEVENTFUL LNDG WAS ACCOMPLISHED. IF WE HAD CONTINUED AS ORIGINALLY CLRED FOR AN APCH TO 24R, IT WOULD HAVE BEEN IMPOSSIBLE TO MAINTAIN VIS CONTACT WITH THE ACR FLT SINCE WE WOULD HAVE BEEN BANKED STEEPLY TO THE RIGHT. THE CAUSE OF THIS SITUATION WAS THE CONGESTED, CHAOTIC AND CONFUSED ENVIRONMENT OF THE LAX APCH AREA. THERE WERE TOO MANY 'PLAN FOR...' INSTRUCTIONS GIVEN WHICH WERE CHANGED. OUR RWY WAS CHANGED JUST AS WE WERE TURNING ON THE BASE LEG. NOTE: IN ORDER TO INCREASE THE VERT SEP FROM THE OTHER ACR FLT, WE DSNDED AND DELAYED OUR TURN TOWARD LAX. THE DSNT RESULTED IN INCREASED AIRSPD AND CAUSED A WIDER RADIUS OF TURN EXACERBATING THE OVERSHOOT. OUR PRIMARY FOCUS WAS MAINTAINING A SAFE SEP FROM THE OTHER ACFT.

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.