Narrative:

While descending to toledo, was cleared from 16000 ft to 14000 ft. I asked for direct tol, and given. I put 14000 ft in altitude alerter and programmed direct tol in GPS. Had autoplt on and at 12200 ft controller asked my assigned altitude. About then I thought cleared to 11000 ft for tol approach, and said 11000 ft. I looked at the alerter and saw 14000 ft. I must have missed the chime and forgot to hit altitude select on autoplt while reprogramming the GPS. A long day and got busy and let my mind do something other than fly the plane.

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Original NASA ASRS Text

Title: CAPT OF A CESSNA CITATION OVERSHOT ASSIGNED ALT ON DSCNT.

Narrative: WHILE DSNDING TO TOLEDO, WAS CLRED FROM 16000 FT TO 14000 FT. I ASKED FOR DIRECT TOL, AND GIVEN. I PUT 14000 FT IN ALT ALERTER AND PROGRAMMED DIRECT TOL IN GPS. HAD AUTOPLT ON AND AT 12200 FT CTLR ASKED MY ASSIGNED ALT. ABOUT THEN I THOUGHT CLRED TO 11000 FT FOR TOL APCH, AND SAID 11000 FT. I LOOKED AT THE ALERTER AND SAW 14000 FT. I MUST HAVE MISSED THE CHIME AND FORGOT TO HIT ALT SELECT ON AUTOPLT WHILE REPROGRAMMING THE GPS. A LONG DAY AND GOT BUSY AND LET MY MIND DO SOMETHING OTHER THAN FLY THE PLANE.

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.