Narrative:

On level-off from climb out on a leg from atlanta to philadelphia the captain engaged the altitude hold feature of the autoplt. The crew believed the feature was working properly and that the aircraft was level. The crew then focused on scans at their own crew station. Moments later the captain noticed the aircraft climbing at 500 FPM through FL335. He immediately corrected the excursion. Since no aural warning was given by onboard system, I am unsure as to how a flight engineer can better monitor altitude when tending to duties on the rear panel. Possibly an aural alert that would sound with a 250-300 ft deviation would prevent further excursions.

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Original NASA ASRS Text

Title: AN ACR B727 FLC, APPARENTLY, ENGAGED THE ALT HOLD MODE OF THE AUTOPLT, BUT THE ACFT STILL CLBED ABOVE ITS ASSIGNED ALT.

Narrative: ON LEVEL-OFF FROM CLBOUT ON A LEG FROM ATLANTA TO PHILADELPHIA THE CAPT ENGAGED THE ALT HOLD FEATURE OF THE AUTOPLT. THE CREW BELIEVED THE FEATURE WAS WORKING PROPERLY AND THAT THE ACFT WAS LEVEL. THE CREW THEN FOCUSED ON SCANS AT THEIR OWN CREW STATION. MOMENTS LATER THE CAPT NOTICED THE ACFT CLBING AT 500 FPM THROUGH FL335. HE IMMEDIATELY CORRECTED THE EXCURSION. SINCE NO AURAL WARNING WAS GIVEN BY ONBOARD SYS, I AM UNSURE AS TO HOW A FE CAN BETTER MONITOR ALT WHEN TENDING TO DUTIES ON THE REAR PANEL. POSSIBLY AN AURAL ALERT THAT WOULD SOUND WITH A 250-300 FT DEV WOULD PREVENT FURTHER EXCURSIONS.

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.