Narrative:

On descent into lax, air carrier widebody transport flight was cleared to filmore, sadde 4 arrival. We crossed 'symon' at 12000 ft and 280 KTS as depicted. I glanced at the arrival chart and saw 'bayst' at 10000 ft. I began a descent after confirming that with the captain. I began the level off when lax approach control issued an immediate left turn to 070 degrees. At the same time I was in the aircraft of changing my course selector to 081 degree sfo the inbound radial to santa monica, VOR, and switching my VOR selector to smo. I began the turn to left immediately. As I scanned the airspeed, altitude, and vsi I noticed a TCASII target to our right and above us. I looked outside but did not see an aircraft, so I tightened my turn. I was manually flying the aircraft. Lax approach control then cleared us to 8000 ft and direct smo VOR. We continued approach and landed runway 24R. As we rolled out the tower advised that 'in the future we should expect 10000 ft over bayst intersection, but this time, no harm, no foul.' contributing factors would be: somewhat tired after any transpacific, having received clearance to 10000 ft every time in the past, we were habit prone. 'Expect' should be more prominent on chart. Possible corrections: remove altitudes from chart, unless they are mandatory. Since you are already at 12000 ft and 280 KTS, it is not difficult to slow/descend if instructed! Why include 'maybe's' and 'possibly's' on arrival plate. It is just busy work and clutters up the arrival. Supplemental information from acn 242453: as we approached symon, the first officer stated 'we are to cross bayst at 10000 ft, right?' I glanced at the sadde 4 arrival and confirmed the 10000 ft which was an error on our part (sadde 4 states expect 10000 ft at bayst).

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Original NASA ASRS Text

Title: AN ACR WDB CREW DSNDED THROUGH ITS ASSIGNED ALT TO AN 'EXPECT' ALT AS SHOWN ON THE STAR.

Narrative: ON DSCNT INTO LAX, ACR WDB FLT WAS CLRED TO FILMORE, SADDE 4 ARR. WE CROSSED 'SYMON' AT 12000 FT AND 280 KTS AS DEPICTED. I GLANCED AT THE ARR CHART AND SAW 'BAYST' AT 10000 FT. I BEGAN A DSCNT AFTER CONFIRMING THAT WITH THE CAPT. I BEGAN THE LEVEL OFF WHEN LAX APCH CTL ISSUED AN IMMEDIATE L TURN TO 070 DEGS. AT THE SAME TIME I WAS IN THE ACFT OF CHANGING MY COURSE SELECTOR TO 081 DEG SFO THE INBOUND RADIAL TO SANTA MONICA, VOR, AND SWITCHING MY VOR SELECTOR TO SMO. I BEGAN THE TURN TO L IMMEDIATELY. AS I SCANNED THE AIRSPD, ALT, AND VSI I NOTICED A TCASII TARGET TO OUR R AND ABOVE US. I LOOKED OUTSIDE BUT DID NOT SEE AN ACFT, SO I TIGHTENED MY TURN. I WAS MANUALLY FLYING THE ACFT. LAX APCH CTL THEN CLRED US TO 8000 FT AND DIRECT SMO VOR. WE CONTINUED APCH AND LANDED RWY 24R. AS WE ROLLED OUT THE TWR ADVISED THAT 'IN THE FUTURE WE SHOULD EXPECT 10000 FT OVER BAYST INTXN, BUT THIS TIME, NO HARM, NO FOUL.' CONTRIBUTING FACTORS WOULD BE: SOMEWHAT TIRED AFTER ANY TRANSPACIFIC, HAVING RECEIVED CLRNC TO 10000 FT EVERY TIME IN THE PAST, WE WERE HABIT PRONE. 'EXPECT' SHOULD BE MORE PROMINENT ON CHART. POSSIBLE CORRECTIONS: REMOVE ALTS FROM CHART, UNLESS THEY ARE MANDATORY. SINCE YOU ARE ALREADY AT 12000 FT AND 280 KTS, IT IS NOT DIFFICULT TO SLOW/DSND IF INSTRUCTED! WHY INCLUDE 'MAYBE'S' AND 'POSSIBLY'S' ON ARR PLATE. IT IS JUST BUSY WORK AND CLUTTERS UP THE ARR. SUPPLEMENTAL INFO FROM ACN 242453: AS WE APCHED SYMON, THE FO STATED 'WE ARE TO CROSS BAYST AT 10000 FT, RIGHT?' I GLANCED AT THE SADDE 4 ARR AND CONFIRMED THE 10000 FT WHICH WAS AN ERROR ON OUR PART (SADDE 4 STATES EXPECT 10000 FT AT BAYST).

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.