Narrative:

Descending to 16000 ft, the autoplt failed to operate normally. Went into capture mode, but never went into a decreasing leveloff. Had to disconnect autoplt and manually level back off. Descended to approximately 15600 ft before climbing back to 16000 ft. Wrote up autoplt for maintenance to fix.

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Original NASA ASRS Text

Title: AN ACR CAPT RPTED THAT THE AUTOPLT MALFUNCTIONED, CAUSING HIM TO DSND FROM THE ASSIGNED ALT IN ZHU AIRSPACE.

Narrative: DSNDING TO 16000 FT, THE AUTOPLT FAILED TO OPERATE NORMALLY. WENT INTO CAPTURE MODE, BUT NEVER WENT INTO A DECREASING LEVELOFF. HAD TO DISCONNECT AUTOPLT AND MANUALLY LEVEL BACK OFF. DSNDED TO APPROX 15600 FT BEFORE CLBING BACK TO 16000 FT. WROTE UP AUTOPLT FOR MAINT TO FIX.

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.