Narrative:

I was the PF, FMC was in VNAV and heading. We were VFR avoiding a thunderstorm cleared direct sji when able. As we passed thunderstorm, I executed a direct sji and engaged LNAV. Center cleared us to FL240 pilot's discretion after FL290, selected 24000 ft, selected 24000 ft in altitude window and selected then engaged 'capture' in the VNAV mode. Aircraft started a descent and center cleared us to an intersection. We were unable to find the fix on the high chart, asked center for spelling, was not in navigation database. I found the fix on the low chart, asked first officer to put it in navigation page, I had to define fix to the FMC and got the aircraft on route. As I engaged LNAV, center asked our altitude. First officer replied 33500 ft descending, while I was defining and getting the FMC to go direct, VNAV disengaged. I was sure descent would continue in vertical speed mode, but pitch command was annunciated, autoplt had no pitch except control wheel steering. Aircraft started a slight climb, corrected and made proper descent, no further events. Factors: first leg of flight series, new first officer just out of initial operating experience. He didn't know how to fine the fix and had problems with FMC use. He was keenly watching what I was doing and paid no attention to flight profile. I was overloaded due to having to do all the work myself. Autoflt had some reoccurring problems the rest of the day, occasional pitch or roll control wheel steering annunciated during FMC flight. I assume this was not normal, but couldn't duplicate problems. It was just an intermittent problem, and corrected itself on the third leg. I suspect a possible alignment error caused by improper align procedures done by first officer. When I did a full alignment on the third leg, no further problems.

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Original NASA ASRS Text

Title: ALTDEV ALT EXCURSION - ACR CREW CLBS INSTEAD OF DSNDING AS THE CLRNC REQUIRED.

Narrative: I WAS THE PF, FMC WAS IN VNAV AND HDG. WE WERE VFR AVOIDING A TSTM CLRED DIRECT SJI WHEN ABLE. AS WE PASSED TSTM, I EXECUTED A DIRECT SJI AND ENGAGED LNAV. CTR CLRED US TO FL240 PLT'S DISCRETION AFTER FL290, SELECTED 24000 FT, SELECTED 24000 FT IN ALT WINDOW AND SELECTED THEN ENGAGED 'CAPTURE' IN THE VNAV MODE. ACFT STARTED A DSCNT AND CTR CLRED US TO AN INTXN. WE WERE UNABLE TO FIND THE FIX ON THE HIGH CHART, ASKED CTR FOR SPELLING, WAS NOT IN NAV DATABASE. I FOUND THE FIX ON THE LOW CHART, ASKED FO TO PUT IT IN NAV PAGE, I HAD TO DEFINE FIX TO THE FMC AND GOT THE ACFT ON RTE. AS I ENGAGED LNAV, CTR ASKED OUR ALT. FO REPLIED 33500 FT DSNDING, WHILE I WAS DEFINING AND GETTING THE FMC TO GO DIRECT, VNAV DISENGAGED. I WAS SURE DSCNT WOULD CONTINUE IN VERT SPD MODE, BUT PITCH COMMAND WAS ANNUNCIATED, AUTOPLT HAD NO PITCH EXCEPT CTL WHEEL STEERING. ACFT STARTED A SLIGHT CLB, CORRECTED AND MADE PROPER DSCNT, NO FURTHER EVENTS. FACTORS: FIRST LEG OF FLT SERIES, NEW FO JUST OUT OF INITIAL OPERATING EXPERIENCE. HE DIDN'T KNOW HOW TO FINE THE FIX AND HAD PROBS WITH FMC USE. HE WAS KEENLY WATCHING WHAT I WAS DOING AND PAID NO ATTN TO FLT PROFILE. I WAS OVERLOADED DUE TO HAVING TO DO ALL THE WORK MYSELF. AUTOFLT HAD SOME REOCCURRING PROBS THE REST OF THE DAY, OCCASIONAL PITCH OR ROLL CTL WHEEL STEERING ANNUNCIATED DURING FMC FLT. I ASSUME THIS WAS NOT NORMAL, BUT COULDN'T DUPLICATE PROBS. IT WAS JUST AN INTERMITTENT PROB, AND CORRECTED ITSELF ON THE THIRD LEG. I SUSPECT A POSSIBLE ALIGNMENT ERROR CAUSED BY IMPROPER ALIGN PROCS DONE BY FO. WHEN I DID A FULL ALIGNMENT ON THE THIRD LEG, NO FURTHER PROBS.

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.