Narrative:

The captain was the PF, the autoplt was engaged, and he was making the FMS entries and selections on the MCP. He had programmed the FMS VNAV to cross cedes intersection at 250 KTS and 11000 ft altitude, as depicted on the modesto 2 STAR. I confirmed this entry as correct. ZOA cleared us to 'cross cedes at 11000 ft, 250 KTS,' which is what I read back. At that time the lead flight attendant came forward with 2 cabin discrepancies. I briefly reviewed them to see if they were considered 'airworthiness items' by our company policy, as those require a logbook entry. This all took about 1 min. I then put that task aside to be completed on the ground after shutdown. I feel that this distraction broke down my PNF habit patterns of backup and confirmation of the PF's navigation. Our company promotes the 'double point' altitude confirmation technique for what altitude is set in the MCP. Because of the flight attendant call bell, I don't recall pointing to the altitude window after the captain was supposed to enter 11000 ft. After the distraction, I remember glancing at the window and I thought for sure I saw 11000 ft, but in hindsight I wonder if it really was 10000 ft and I saw what I expected to see instead. The captain thought he had 11000 ft in and does not know how 10000 ft got selected unless we had subsequently been cleared to 10000 ft. I have read that ten and eleven thousand ft are the most often confused altitudes, and I believe it. In the future I intend to train myself to be extra vigilant with clrncs and setting to those altitudes. The last chance to break the chain of events came with the ATC handoff to approach control. Because of congestion on the frequency, approach control called us first with a spacing vector behind a B747. This is not at all unusual in a busy terminal environment. The radio chatter is non stop. The controller knows you are on frequency but can't find a clear moment to check in, so he just starts telling you what to do. It happened 3 or 4 times on this 5-DAY trip. If I had initiated the check-in with approach control, I would have included the altitude we were descending to and perhaps he would have caught the error them. The lesson learned here is that if the controller initiates initial communication, read back your altitude assignment with whatever other clearance or information ATC included for you in the initial transmission. Anyway, we leveled at 10000 ft and got yelled at by the approach controller. We did not detect any conflicts with other traffic either visually or on the TCASII, so I hope no 'loss of separation' occurred. Bottom line: avoid distrs during climbs and dscnts, 'double point,' watch confusing the 10's and 11's, call out approaching one's assigned altitudes, and announce one's current and cleared-to altitudes to ATC -- even if one must tack the information onto another readback.

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Original NASA ASRS Text

Title: AN ACR FLC OVERSHOOTS THEIR ASSIGNED XING ALT FOR CEDES INTXN NEAR MOD, CA.

Narrative: THE CAPT WAS THE PF, THE AUTOPLT WAS ENGAGED, AND HE WAS MAKING THE FMS ENTRIES AND SELECTIONS ON THE MCP. HE HAD PROGRAMMED THE FMS VNAV TO CROSS CEDES INTXN AT 250 KTS AND 11000 FT ALT, AS DEPICTED ON THE MODESTO 2 STAR. I CONFIRMED THIS ENTRY AS CORRECT. ZOA CLRED US TO 'CROSS CEDES AT 11000 FT, 250 KTS,' WHICH IS WHAT I READ BACK. AT THAT TIME THE LEAD FLT ATTENDANT CAME FORWARD WITH 2 CABIN DISCREPANCIES. I BRIEFLY REVIEWED THEM TO SEE IF THEY WERE CONSIDERED 'AIRWORTHINESS ITEMS' BY OUR COMPANY POLICY, AS THOSE REQUIRE A LOGBOOK ENTRY. THIS ALL TOOK ABOUT 1 MIN. I THEN PUT THAT TASK ASIDE TO BE COMPLETED ON THE GND AFTER SHUTDOWN. I FEEL THAT THIS DISTR BROKE DOWN MY PNF HABIT PATTERNS OF BACKUP AND CONFIRMATION OF THE PF'S NAV. OUR COMPANY PROMOTES THE 'DOUBLE POINT' ALT CONFIRMATION TECHNIQUE FOR WHAT ALT IS SET IN THE MCP. BECAUSE OF THE FLT ATTENDANT CALL BELL, I DON'T RECALL POINTING TO THE ALT WINDOW AFTER THE CAPT WAS SUPPOSED TO ENTER 11000 FT. AFTER THE DISTR, I REMEMBER GLANCING AT THE WINDOW AND I THOUGHT FOR SURE I SAW 11000 FT, BUT IN HINDSIGHT I WONDER IF IT REALLY WAS 10000 FT AND I SAW WHAT I EXPECTED TO SEE INSTEAD. THE CAPT THOUGHT HE HAD 11000 FT IN AND DOES NOT KNOW HOW 10000 FT GOT SELECTED UNLESS WE HAD SUBSEQUENTLY BEEN CLRED TO 10000 FT. I HAVE READ THAT TEN AND ELEVEN THOUSAND FT ARE THE MOST OFTEN CONFUSED ALTS, AND I BELIEVE IT. IN THE FUTURE I INTEND TO TRAIN MYSELF TO BE EXTRA VIGILANT WITH CLRNCS AND SETTING TO THOSE ALTS. THE LAST CHANCE TO BREAK THE CHAIN OF EVENTS CAME WITH THE ATC HDOF TO APCH CTL. BECAUSE OF CONGESTION ON THE FREQ, APCH CTL CALLED US FIRST WITH A SPACING VECTOR BEHIND A B747. THIS IS NOT AT ALL UNUSUAL IN A BUSY TERMINAL ENVIRONMENT. THE RADIO CHATTER IS NON STOP. THE CTLR KNOWS YOU ARE ON FREQ BUT CAN'T FIND A CLR MOMENT TO CHK IN, SO HE JUST STARTS TELLING YOU WHAT TO DO. IT HAPPENED 3 OR 4 TIMES ON THIS 5-DAY TRIP. IF I HAD INITIATED THE CHK-IN WITH APCH CTL, I WOULD HAVE INCLUDED THE ALT WE WERE DSNDING TO AND PERHAPS HE WOULD HAVE CAUGHT THE ERROR THEM. THE LESSON LEARNED HERE IS THAT IF THE CTLR INITIATES INITIAL COM, READ BACK YOUR ALT ASSIGNMENT WITH WHATEVER OTHER CLRNC OR INFO ATC INCLUDED FOR YOU IN THE INITIAL XMISSION. ANYWAY, WE LEVELED AT 10000 FT AND GOT YELLED AT BY THE APCH CTLR. WE DID NOT DETECT ANY CONFLICTS WITH OTHER TFC EITHER VISUALLY OR ON THE TCASII, SO I HOPE NO 'LOSS OF SEPARATION' OCCURRED. BOTTOM LINE: AVOID DISTRS DURING CLBS AND DSCNTS, 'DOUBLE POINT,' WATCH CONFUSING THE 10'S AND 11'S, CALL OUT APCHING ONE'S ASSIGNED ALTS, AND ANNOUNCE ONE'S CURRENT AND CLRED-TO ALTS TO ATC -- EVEN IF ONE MUST TACK THE INFO ONTO ANOTHER READBACK.

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.