Narrative:

Just prior to reaching the pdz VOR on the pdz arrival into lax, the approach controller told us to cross mitts intersection at 250 KTS and 10000 ft. I said that we were cleared on the pdz arrival and the controller again told us to cross mitts intersection at 250 KTS, 10000 ft. We then realized that mitts also appeared as an intersection on the pdz arrival for runway 24R, which socal had just changed us to from runway 25L. My first officer confirmed with me that we were cleared to 10000 ft. He then initiated a slow descent from 12000 ft 50 10000 ft. At 11100 ft, approach said that we had a 12000 ft crossing restr 2 mi. My first officer immediately leveled off at 11000 ft for the next 2 mi and then continued to the original published 10000 ft. We both assumed we were immediately cleared to 10000 ft.

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Original NASA ASRS Text

Title: A FLC DSNDED BELOW AN ALT RESTR ON ARR TO LAX.

Narrative: JUST PRIOR TO REACHING THE PDZ VOR ON THE PDZ ARR INTO LAX, THE APCH CTLR TOLD US TO CROSS MITTS INTXN AT 250 KTS AND 10000 FT. I SAID THAT WE WERE CLRED ON THE PDZ ARR AND THE CTLR AGAIN TOLD US TO CROSS MITTS INTXN AT 250 KTS, 10000 FT. WE THEN REALIZED THAT MITTS ALSO APPEARED AS AN INTXN ON THE PDZ ARR FOR RWY 24R, WHICH SOCAL HAD JUST CHANGED US TO FROM RWY 25L. MY FO CONFIRMED WITH ME THAT WE WERE CLRED TO 10000 FT. HE THEN INITIATED A SLOW DSCNT FROM 12000 FT 50 10000 FT. AT 11100 FT, APCH SAID THAT WE HAD A 12000 FT XING RESTR 2 MI. MY FO IMMEDIATELY LEVELED OFF AT 11000 FT FOR THE NEXT 2 MI AND THEN CONTINUED TO THE ORIGINAL PUBLISHED 10000 FT. WE BOTH ASSUMED WE WERE IMMEDIATELY CLRED TO 10000 FT.

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.