Narrative:

Halfway through a 10 leg, 10 hour duty day while step climbing towards our cruise altitude, center told us to 'climb and maintain 12000, expect 13000.' the PNF acknowledged this and put 12000 in the altitude box. As we were climbing through 12300 at 1000 FPM center advised us to climb and maintain 13000. Fortunately ATC notified us to climb before any further altitude deviation occurred and any traffic separation was jeopardized. The factors leading up to this event were a long time in the making. Long duty days with quick ground turns are common and the opportunity to 'catch our breath' is very limited. In this particular event the PF and PNF were not as attentive as we should have or could have been to the situation at hand. I, PF, had in my mind the altitude of 13000 which was the last altitude I had heard spoken instead of 12000 which we were told to maintain. Lesson learned in this event was to pay closer attention to the critical phases of flight no matter how mentally and physically taxing our flying schedule is. Supplemental information from acn 262032: I was hungry and this was the only leg long enough to eat on. Needless to say I was thinking more about food than flying. My first officer misunderstood the clearance and continued to climb to 13000. I noticed his error as he climbed through 124000. Just as I started to say something, center came on and cleared us to 13000. Related factors in this include a 10 leg workday with no meal breaks, my own complacency, and improper crew coordination.

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Original NASA ASRS Text

Title: ALT BUST

Narrative: HALFWAY THROUGH A 10 LEG, 10 HR DUTY DAY WHILE STEP CLBING TOWARDS OUR CRUISE ALT, CTR TOLD US TO 'CLB AND MAINTAIN 12000, EXPECT 13000.' THE PNF ACKNOWLEDGED THIS AND PUT 12000 IN THE ALT BOX. AS WE WERE CLBING THROUGH 12300 AT 1000 FPM CTR ADVISED US TO CLB AND MAINTAIN 13000. FORTUNATELY ATC NOTIFIED US TO CLB BEFORE ANY FURTHER ALTDEV OCCURRED AND ANY TFC SEPARATION WAS JEOPARDIZED. THE FACTORS LEADING UP TO THIS EVENT WERE A LONG TIME IN THE MAKING. LONG DUTY DAYS WITH QUICK GND TURNS ARE COMMON AND THE OPPORTUNITY TO 'CATCH OUR BREATH' IS VERY LIMITED. IN THIS PARTICULAR EVENT THE PF AND PNF WERE NOT AS ATTENTIVE AS WE SHOULD HAVE OR COULD HAVE BEEN TO THE SIT AT HAND. I, PF, HAD IN MY MIND THE ALT OF 13000 WHICH WAS THE LAST ALT I HAD HEARD SPOKEN INSTEAD OF 12000 WHICH WE WERE TOLD TO MAINTAIN. LESSON LEARNED IN THIS EVENT WAS TO PAY CLOSER ATTN TO THE CRITICAL PHASES OF FLT NO MATTER HOW MENTALLY AND PHYSICALLY TAXING OUR FLYING SCHEDULE IS. SUPPLEMENTAL INFO FROM ACN 262032: I WAS HUNGRY AND THIS WAS THE ONLY LEG LONG ENOUGH TO EAT ON. NEEDLESS TO SAY I WAS THINKING MORE ABOUT FOOD THAN FLYING. MY FO MISUNDERSTOOD THE CLRNC AND CONTINUED TO CLB TO 13000. I NOTICED HIS ERROR AS HE CLBED THROUGH 124000. JUST AS I STARTED TO SAY SOMETHING, CTR CAME ON AND CLRED US TO 13000. RELATED FACTORS IN THIS INCLUDE A 10 LEG WORKDAY WITH NO MEAL BREAKS, MY OWN COMPLACENCY, AND IMPROPER CREW COORD.

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.