Narrative:

Descending into lax on the pdz 4 STAR, we were stepping down. Passing pdz, we set up runway 24R approach. The controller said unable approach. While passing the IAF turn (arnes), they had us expedite descent. Doing both rapidly got us behind, being task saturated. Being new to this FMS airplane didn't help the situation. Setting up the approach, checking each fix/course/altitude took a few moments to make sure we didn't execute anything incorrectly. Trying to decipher between what raw data said and the FMS gave us a moment of question. We ended up being just north of the runway 24R localizer, where turned back to a heading to reintercept runway 25L localizer. We tried to repos ourselves back into the line-up where we belonged. Approach control came back, gave us heading/altitude to rejoin runway 25L final course. At no point were we lost, too low or was safety in jeopardy. We were vectored back into line, descended on the approach as charted and landed without incident.

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Original NASA ASRS Text

Title: HDG TRACK DEV WHEN AN ACR FMS TYPE ACFT IS ASSIGNED ANOTHER RWY AND THE FO, PF, APPEARED TO HAVE A DIFFICULT TIME IN MAKING THE REQUIRED FMS CHANGES TO COMPLY WITH THE NEW CLRNC, 40 MI E OF LAX, CA.

Narrative: DSNDING INTO LAX ON THE PDZ 4 STAR, WE WERE STEPPING DOWN. PASSING PDZ, WE SET UP RWY 24R APCH. THE CTLR SAID UNABLE APCH. WHILE PASSING THE IAF TURN (ARNES), THEY HAD US EXPEDITE DSCNT. DOING BOTH RAPIDLY GOT US BEHIND, BEING TASK SATURATED. BEING NEW TO THIS FMS AIRPLANE DIDN'T HELP THE SIT. SETTING UP THE APCH, CHKING EACH FIX/COURSE/ALT TOOK A FEW MOMENTS TO MAKE SURE WE DIDN'T EXECUTE ANYTHING INCORRECTLY. TRYING TO DECIPHER BTWN WHAT RAW DATA SAID AND THE FMS GAVE US A MOMENT OF QUESTION. WE ENDED UP BEING JUST N OF THE RWY 24R LOC, WHERE TURNED BACK TO A HDG TO REINTERCEPT RWY 25L LOC. WE TRIED TO REPOS OURSELVES BACK INTO THE LINE-UP WHERE WE BELONGED. APCH CTL CAME BACK, GAVE US HDG/ALT TO REJOIN RWY 25L FINAL COURSE. AT NO POINT WERE WE LOST, TOO LOW OR WAS SAFETY IN JEOPARDY. WE WERE VECTORED BACK INTO LINE, DSNDED ON THE APCH AS CHARTED AND LANDED WITHOUT INCIDENT.

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.