Narrative:

Hand flying lear jet at about FL230 or FL270, do not recall which, when a passenger asked captain, who was myself, a question. I told copilot that he had the aircraft and turned my head to rear to address passenger. Approximately 10 seconds later, I heard altitude alerter go off and saw airplane approximately 500 ft high. I immediately informed copilot I had control of aircraft and returned to and maintained assigned flight level. ATC -- ZHU mobile section? -- Asked what my altitude was and I said that I was leveling assigned flight level or something like that. After the flight the copilot and I debriefed the incident and he said he understood that he had control of the aircraft and that he did not know the aircraft was not on autoplt and that at our en route airspeed/mach that the airplane just got away from him. We decided that in the future the PF will inform the PNF the aircraft autoplt status and any other pertinent information (ie, on vectors, proceeding direct, maintain course, descending to, etc) and insure the pilot accepting command verifies that status.

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Original NASA ASRS Text

Title: A PVT LEAR JET MODEL 23 FLC CLBS 500 FT ABOVE THEIR ASSIGNED ALT WHEN THE CAPT TRANSFERS CTL TO THE FO WITHOUT TELLING HIM THAT THEY ARE NOT ON AUTOPLT.

Narrative: HAND FLYING LEAR JET AT ABOUT FL230 OR FL270, DO NOT RECALL WHICH, WHEN A PAX ASKED CAPT, WHO WAS MYSELF, A QUESTION. I TOLD COPLT THAT HE HAD THE ACFT AND TURNED MY HEAD TO REAR TO ADDRESS PAX. APPROX 10 SECONDS LATER, I HEARD ALT ALERTER GO OFF AND SAW AIRPLANE APPROX 500 FT HIGH. I IMMEDIATELY INFORMED COPLT I HAD CTL OF ACFT AND RETURNED TO AND MAINTAINED ASSIGNED FLT LEVEL. ATC -- ZHU MOBILE SECTION? -- ASKED WHAT MY ALT WAS AND I SAID THAT I WAS LEVELING ASSIGNED FLT LEVEL OR SOMETHING LIKE THAT. AFTER THE FLT THE COPLT AND I DEBRIEFED THE INCIDENT AND HE SAID HE UNDERSTOOD THAT HE HAD CTL OF THE ACFT AND THAT HE DID NOT KNOW THE ACFT WAS NOT ON AUTOPLT AND THAT AT OUR ENRTE AIRSPD/MACH THAT THE AIRPLANE JUST GOT AWAY FROM HIM. WE DECIDED THAT IN THE FUTURE THE PF WILL INFORM THE PNF THE ACFT AUTOPLT STATUS AND ANY OTHER PERTINENT INFO (IE, ON VECTORS, PROCEEDING DIRECT, MAINTAIN COURSE, DSNDING TO, ETC) AND INSURE THE PLT ACCEPTING COMMAND VERIFIES THAT STATUS.

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.