Narrative:

Autoplt disengaged at FL190. Crew (first officer) was tuning radios and talking to approach control. Captain was reading holding instructions to a new holding pattern obscurely presented on approach page into gatwick, england. Gradual descent 700 ft below before arrested and returned to altitude. This is third such occurrence within a yr on the tristar (L1011).

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Original NASA ASRS Text

Title: FLC OF AN L1011 TRISTAR DSNDED BELOW ASSIGNED ALT WHEN THE AUTOPLT DISCONNECTED WHILE CREW WERE DISTR DOING OTHER TASKS.

Narrative: AUTOPLT DISENGAGED AT FL190. CREW (FO) WAS TUNING RADIOS AND TALKING TO APCH CTL. CAPT WAS READING HOLDING INSTRUCTIONS TO A NEW HOLDING PATTERN OBSCURELY PRESENTED ON APCH PAGE INTO GATWICK, ENGLAND. GRADUAL DSCNT 700 FT BELOW BEFORE ARRESTED AND RETURNED TO ALT. THIS IS THIRD SUCH OCCURRENCE WITHIN A YR ON THE TRISTAR (L1011).

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.