Narrative:

We completely briefed the seavu arrival and approach to runway 24R well before descent. ATC gave us a descent via the seavu arrival and to cross konzl at 17;000 ft 280 KTS. After crossing konzl at 17;000 ft 280 KTS; approach gave us runway 25L. I told the first officer to program the runway 25L approach in the CDU. ATC communications were very busy. As I tried to figure out when we were passing an intersection; I would instruct the first officer to set the next lower altitude. I could see the intxns on the CDU and he would concur and set the next altitude. I know we were at the correct altitudes for the first two intxns (turtl and cataw). Here is where things started to happen. I believe the first officer went to the next page to put in the altitude restrs on the approach that do not automatically load when you select runway 25L. I may have seen an intersection that was in front of seavu and dixxn and assumed we were past those points and the first officer again concurred with the next lower altitude. I continued the descent and checked the CDU once again and noticed I had not crossed dixxn yet. I immediately climbed back to 12;000 ft (from 11;300 ft) and crossed dixxn at 12;000 ft. At no time did ATC inquire about our altitude. For that fact; ATC gave me a speed reduction while I was correcting back to 12000 ft. The remainder of the approach and landing were uneventful. Looking back; ATC gave us the runway late (I think he was trying to work us into the runway 24R pattern). Trying to fly one of the most complicated apches in our system with one CDU and no moving map is totally unacceptable in today's environment. A bare minimum should be with two CDU's in the aircraft. Two CDU's and/or a moving map would have greatly reduced the possibility of this happening.

Related reports:

Google
 

Original NASA ASRS Text

Title: LATE RWY CHANGE ON SEAVU STAR TO LAX CAUSES BREAKDOWN IN FLT CREW SITUATIONAL AWARENESS. ALT DEV RESULTS.

Narrative: WE COMPLETELY BRIEFED THE SEAVU ARR AND APCH TO RWY 24R WELL BEFORE DSCNT. ATC GAVE US A DSCNT VIA THE SEAVU ARR AND TO CROSS KONZL AT 17;000 FT 280 KTS. AFTER CROSSING KONZL AT 17;000 FT 280 KTS; APCH GAVE US RWY 25L. I TOLD THE FO TO PROGRAM THE RWY 25L APCH IN THE CDU. ATC COMS WERE VERY BUSY. AS I TRIED TO FIGURE OUT WHEN WE WERE PASSING AN INTXN; I WOULD INSTRUCT THE FO TO SET THE NEXT LOWER ALTITUDE. I COULD SEE THE INTXNS ON THE CDU AND HE WOULD CONCUR AND SET THE NEXT ALTITUDE. I KNOW WE WERE AT THE CORRECT ALTITUDES FOR THE FIRST TWO INTXNS (TURTL AND CATAW). HERE IS WHERE THINGS STARTED TO HAPPEN. I BELIEVE THE FO WENT TO THE NEXT PAGE TO PUT IN THE ALTITUDE RESTRS ON THE APCH THAT DO NOT AUTOMATICALLY LOAD WHEN YOU SELECT RWY 25L. I MAY HAVE SEEN AN INTXN THAT WAS IN FRONT OF SEAVU AND DIXXN AND ASSUMED WE WERE PAST THOSE POINTS AND THE FO AGAIN CONCURRED WITH THE NEXT LOWER ALTITUDE. I CONTINUED THE DSCNT AND CHECKED THE CDU ONCE AGAIN AND NOTICED I HAD NOT CROSSED DIXXN YET. I IMMEDIATELY CLIMBED BACK TO 12;000 FT (FROM 11;300 FT) AND CROSSED DIXXN AT 12;000 FT. AT NO TIME DID ATC INQUIRE ABOUT OUR ALTITUDE. FOR THAT FACT; ATC GAVE ME A SPEED REDUCTION WHILE I WAS CORRECTING BACK TO 12000 FT. THE REMAINDER OF THE APCH AND LNDG WERE UNEVENTFUL. LOOKING BACK; ATC GAVE US THE RWY LATE (I THINK HE WAS TRYING TO WORK US INTO THE RWY 24R PATTERN). TRYING TO FLY ONE OF THE MOST COMPLICATED APCHES IN OUR SYSTEM WITH ONE CDU AND NO MOVING MAP IS TOTALLY UNACCEPTABLE IN TODAY'S ENVIRONMENT. A BARE MINIMUM SHOULD BE WITH TWO CDU'S IN THE ACFT. TWO CDU'S AND/OR A MOVING MAP WOULD HAVE GREATLY REDUCED THE POSSIBILITY OF THIS HAPPENING.

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.