Narrative:

Departure clearance: after takeoff turn left to 090 degrees, climb to 3100 ft. Tower hands off to departure. Departure amends to 3000 ft for traffic. I engage altitude hold at 3000 ft. Altitude hold light comes on. I look down in seat beside me for chart. As I look back up, departure asks for altitude. I see that I am at 3350 ft and report that to departure. I pitch down and return to 3000 ft and inform departure of my autoplt malfunction. Altitude hold does not work for duration of flight. Plan to have autoplt checked out.

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Original NASA ASRS Text

Title: PLT OF A BEECH BARON BE58 CLBED ABOVE ASSIGNED ALT DURING DEP DUE TO THE AUTOPLT ALT HOLD MODE NOT WORKING. CTLR INTERVENED AND RPTR RETURNED TO ASSIGNED.

Narrative: DEP CLRNC: AFTER TKOF TURN L TO 090 DEGS, CLB TO 3100 FT. TWR HANDS OFF TO DEP. DEP AMENDS TO 3000 FT FOR TFC. I ENGAGE ALT HOLD AT 3000 FT. ALT HOLD LIGHT COMES ON. I LOOK DOWN IN SEAT BESIDE ME FOR CHART. AS I LOOK BACK UP, DEP ASKS FOR ALT. I SEE THAT I AM AT 3350 FT AND RPT THAT TO DEP. I PITCH DOWN AND RETURN TO 3000 FT AND INFORM DEP OF MY AUTOPLT MALFUNCTION. ALT HOLD DOES NOT WORK FOR DURATION OF FLT. PLAN TO HAVE AUTOPLT CHKED OUT.

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.