Narrative:

While on climb out, gear up light did not illuminate and while checking this initially, flew through heading. After re- establishing heading, I set autoplt for climb then leveled out on heading. Set altitude hold, while troubleshooting light, altitude hold clicked off and aircraft climbed approximately 1000 ft before noted by single pilot on board. I assumed autoplt would fly aircraft while I troubleshot problem. Need to be more cognizant. Airspace clear and good visibility. I frequently checked for traffic and assumed autoplt was holding heading and altitude. Probably would have scanned inside more if in IMC.

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Original NASA ASRS Text

Title: AN IFR C310 RPTR CLBING TO 6000 FT WAS DISTR WHEN THE GEAR UP LIGHT DID NOT ILLUMINATE AND CLBED ABOVE ASSIGNED ALT. NO OTHER TFC INVOLVED.

Narrative: WHILE ON CLB OUT, GEAR UP LIGHT DID NOT ILLUMINATE AND WHILE CHKING THIS INITIALLY, FLEW THROUGH HDG. AFTER RE- ESTABLISHING HDG, I SET AUTOPLT FOR CLB THEN LEVELED OUT ON HDG. SET ALT HOLD, WHILE TROUBLESHOOTING LIGHT, ALT HOLD CLICKED OFF AND ACFT CLBED APPROX 1000 FT BEFORE NOTED BY SINGLE PLT ON BOARD. I ASSUMED AUTOPLT WOULD FLY ACFT WHILE I TROUBLESHOT PROB. NEED TO BE MORE COGNIZANT. AIRSPACE CLR AND GOOD VISIBILITY. I FREQUENTLY CHKED FOR TFC AND ASSUMED AUTOPLT WAS HOLDING HDG AND ALT. PROBABLY WOULD HAVE SCANNED INSIDE MORE IF IN IMC.

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.