Narrative:

I had just gone missed approach at horseshoe bay; tx. NDB 17 (due to low clouds) and exited holding for a direct to sat. While preparing the GPS; finding approach plates; and changing from center frequency to sat approach; the autoplt altitude hold disconnected. I did not catch the error until 6400 ft (400 ft off altitude). My autoplt (kfc 200) has only a blinking light for a disconnect and no warning for a single mode disconnect (like altitude hold). It was a very busy phase of flight (single pilot IFR) in the deviation and I did not catch the error due to a slow crosschk. The only solution is to be more aware of distractions at this busy point and to use a faster crosschk even with the autoplt.

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Original NASA ASRS Text

Title: BE58 SINGLE PLT; DISTRACTED BY REROUTE ACTIVITIES FOLLOWING A MISSED APCH; EXPERIENCES AN ALT DEV WHEN THE ALT HOLD FUNCTION OF THE AUTOPLT FAILED; WITH NO CLR WARNING INDICATION.

Narrative: I HAD JUST GONE MISSED APCH AT HORSESHOE BAY; TX. NDB 17 (DUE TO LOW CLOUDS) AND EXITED HOLDING FOR A DIRECT TO SAT. WHILE PREPARING THE GPS; FINDING APCH PLATES; AND CHANGING FROM CTR FREQ TO SAT APCH; THE AUTOPLT ALT HOLD DISCONNECTED. I DID NOT CATCH THE ERROR UNTIL 6400 FT (400 FT OFF ALT). MY AUTOPLT (KFC 200) HAS ONLY A BLINKING LIGHT FOR A DISCONNECT AND NO WARNING FOR A SINGLE MODE DISCONNECT (LIKE ALT HOLD). IT WAS A VERY BUSY PHASE OF FLT (SINGLE PLT IFR) IN THE DEV AND I DID NOT CATCH THE ERROR DUE TO A SLOW CROSSCHK. THE ONLY SOLUTION IS TO BE MORE AWARE OF DISTRACTIONS AT THIS BUSY POINT AND TO USE A FASTER CROSSCHK EVEN WITH THE AUTOPLT.

Data retrieved from NASA's ASRS site as of January 2009 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.