Narrative:

ATC facility: ZOA. Location: mod 245 degree radial, approximately 16 DME. The altitude deviation occurred after modesto intersection, while on approach and descent to cedes intersection. Both the first officer and I were task saturated with switching from the locke 1 arrival and landing on runway 19L, to the modesto 2 arrival and landing on runway 28R, plus a descent and being given a holding pattern at cedes intersection after passing modesto. I absolutely believe I had heard a descent clearance to 11000 ft for holding at cedes. I am now sure that was a result of me staring at the modesto 2 arrival (which says to expect clearance to cross at 11000 ft, 250 KTS) at the same time ATC issued the descent/holding clearance. I was reprogramming the FMC as the first officer reset the MCP to 17000 ft -- did not catch it. As the aircraft went into altitude capture at 17000 ft, I looked over and saw the 17000 ft in the window and thought it had been incorrectly set. I said 'no, they want us to cross cedes at 11000 ft. Reset the MCP to 11000 ft.' the first officer was busy switching plates to the new arrival and runway, and did not hear me or notice my action. At approximately 15000 ft, ATC asked us to verify our altitude. I replied, 'we are out of 14000 ft, descending to 11000 ft.' ATC said to turn right to 310 degrees and climb to 15000 ft. After accomplishing that, we were turned back to cedes, did 1 turn, and went on in and landed. There were no TCASII alerts. I feel my biggest mistake was not the 11000 ft error, but rather not questioning the first officer as to the altitude he had set.

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Original NASA ASRS Text

Title: AFTER A RWY CHANGE WAS ANNOUNCED FOR SFO, AN INBOUND B767 CREW BECAME BUSY RESETTING NAV EQUIP AND STARTED DSCNT TO THE WRONG ALT.

Narrative: ATC FACILITY: ZOA. LOCATION: MOD 245 DEG RADIAL, APPROX 16 DME. THE ALTDEV OCCURRED AFTER MODESTO INTXN, WHILE ON APCH AND DSCNT TO CEDES INTXN. BOTH THE FO AND I WERE TASK SATURATED WITH SWITCHING FROM THE LOCKE 1 ARR AND LNDG ON RWY 19L, TO THE MODESTO 2 ARR AND LNDG ON RWY 28R, PLUS A DSCNT AND BEING GIVEN A HOLDING PATTERN AT CEDES INTXN AFTER PASSING MODESTO. I ABSOLUTELY BELIEVE I HAD HEARD A DSCNT CLRNC TO 11000 FT FOR HOLDING AT CEDES. I AM NOW SURE THAT WAS A RESULT OF ME STARING AT THE MODESTO 2 ARR (WHICH SAYS TO EXPECT CLRNC TO CROSS AT 11000 FT, 250 KTS) AT THE SAME TIME ATC ISSUED THE DSCNT/HOLDING CLRNC. I WAS REPROGRAMMING THE FMC AS THE FO RESET THE MCP TO 17000 FT -- DID NOT CATCH IT. AS THE ACFT WENT INTO ALT CAPTURE AT 17000 FT, I LOOKED OVER AND SAW THE 17000 FT IN THE WINDOW AND THOUGHT IT HAD BEEN INCORRECTLY SET. I SAID 'NO, THEY WANT US TO CROSS CEDES AT 11000 FT. RESET THE MCP TO 11000 FT.' THE FO WAS BUSY SWITCHING PLATES TO THE NEW ARR AND RWY, AND DID NOT HEAR ME OR NOTICE MY ACTION. AT APPROX 15000 FT, ATC ASKED US TO VERIFY OUR ALT. I REPLIED, 'WE ARE OUT OF 14000 FT, DSNDING TO 11000 FT.' ATC SAID TO TURN R TO 310 DEGS AND CLB TO 15000 FT. AFTER ACCOMPLISHING THAT, WE WERE TURNED BACK TO CEDES, DID 1 TURN, AND WENT ON IN AND LANDED. THERE WERE NO TCASII ALERTS. I FEEL MY BIGGEST MISTAKE WAS NOT THE 11000 FT ERROR, BUT RATHER NOT QUESTIONING THE FO AS TO THE ALT HE HAD SET.

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.