Narrative:

Bright warning lights, horns or aurals not always a nuisance. Center gave vector for traffic. Slewed heading select bug, went to another task, then about 3 seconds later, noticed autoplt had disconnected. Aircraft had gone to about 35 degree bank, going nose low, and losing altitude. Sacrificed some altitude for smoother transition as seat belt sign off. Autoplt light was not bright enough under the lighting conditions. An aural warning would have helped. The small red autoplt light under the bright haze conditions was not discernible enough. Apparently autoplt disconnected as rolling moment was being established then left aircraft in that condition. Happened very fast.

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Original NASA ASRS Text

Title: A COMMERCIAL FIXED WING MLG ACFT IN CRUISE EXPERIENCED AN UNCOMMANDED AUTOPLT DISCONNECT JUST AFTER A HDG SELECT INPUT, CAUSING ALT AND HDG DEV.

Narrative: BRIGHT WARNING LIGHTS, HORNS OR AURALS NOT ALWAYS A NUISANCE. CTR GAVE VECTOR FOR TFC. SLEWED HDG SELECT BUG, WENT TO ANOTHER TASK, THEN ABOUT 3 SECONDS LATER, NOTICED AUTOPLT HAD DISCONNECTED. ACFT HAD GONE TO ABOUT 35 DEG BANK, GOING NOSE LOW, AND LOSING ALT. SACRIFICED SOME ALT FOR SMOOTHER TRANSITION AS SEAT BELT SIGN OFF. AUTOPLT LIGHT WAS NOT BRIGHT ENOUGH UNDER THE LIGHTING CONDITIONS. AN AURAL WARNING WOULD HAVE HELPED. THE SMALL RED AUTOPLT LIGHT UNDER THE BRIGHT HAZE CONDITIONS WAS NOT DISCERNIBLE ENOUGH. APPARENTLY AUTOPLT DISCONNECTED AS ROLLING MOMENT WAS BEING ESTABLISHED THEN LEFT ACFT IN THAT CONDITION. HAPPENED VERY FAST.

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.