Narrative:

Aircraft does not have any 'automatic altitude capture' when on autoplt (non standard with fleet). We made our normal altitude callouts approaching FL290 (2000 ft, 1000 ft before). Just before FL290 our attention must have been diverted from the altimeter (captain and first officer). At FL290 +300 ft we were warned by our altitude alerter. We corrected to descend quickly as possible to FL290. ZLA called at that time to verify altitude. At FL290 +300 ft we had to break the climb by pitching over (without 'floating' passenger). Our maximum altitude deviation was FL290 +500 ft. Time between warning and getting back to FL290 was approximately 15 seconds. TCASII RA or TA did not sound.

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Original NASA ASRS Text

Title: A B727 FLT CREW INADVERTENTLY OVERSHOOT ASSIGNED ALT.

Narrative: ACFT DOES NOT HAVE ANY 'AUTOMATIC ALT CAPTURE' WHEN ON AUTOPLT (NON STANDARD WITH FLEET). WE MADE OUR NORMAL ALT CALLOUTS APCHING FL290 (2000 FT, 1000 FT BEFORE). JUST BEFORE FL290 OUR ATTN MUST HAVE BEEN DIVERTED FROM THE ALTIMETER (CAPT AND FO). AT FL290 +300 FT WE WERE WARNED BY OUR ALT ALERTER. WE CORRECTED TO DSND QUICKLY AS POSSIBLE TO FL290. ZLA CALLED AT THAT TIME TO VERIFY ALT. AT FL290 +300 FT WE HAD TO BREAK THE CLB BY PITCHING OVER (WITHOUT 'FLOATING' PAX). OUR MAX ALTDEV WAS FL290 +500 FT. TIME BTWN WARNING AND GETTING BACK TO FL290 WAS APPROX 15 SECONDS. TCASII RA OR TA DID NOT SOUND.

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.