Narrative:

Aircraft does not have an automatic altitude capture when on autoplt. We made our normal altitude callouts approaching FL290 (2000 ft, 1000 ft before). Just before FL290 our attention (captain/first officer) was diverted from the altimeter at FL290 +300 ft we were warned by our altitude alerter. We corrected to descend quickly to FL290. ZLA called at that time verifying altitude. At FL290 +300 ft we had to break the climb by pitching over. Our maximum altitude deviation was FL290 +500 ft. Time between warning and getting back to FL290 was approximately 15 seconds.

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Original NASA ASRS Text

Title: A B727 CREW OVERSHOOTS THEIR ASSIGNED ALT WHEN THEY BECAME DISTRACTED NEAR THE POINT OF LEVELOFF.

Narrative: ACFT DOES NOT HAVE AN AUTOMATIC ALT CAPTURE WHEN ON AUTOPLT. WE MADE OUR NORMAL ALT CALLOUTS APCHING FL290 (2000 FT, 1000 FT BEFORE). JUST BEFORE FL290 OUR ATTN (CAPT/FO) WAS DIVERTED FROM THE ALTIMETER AT FL290 +300 FT WE WERE WARNED BY OUR ALT ALERTER. WE CORRECTED TO DSND QUICKLY TO FL290. ZLA CALLED AT THAT TIME VERIFYING ALT. AT FL290 +300 FT WE HAD TO BREAK THE CLB BY PITCHING OVER. OUR MAX ALTDEV WAS FL290 +500 FT. TIME BTWN WARNING AND GETTING BACK TO FL290 WAS APPROX 15 SECONDS.

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.