Narrative:

Showed up at my plane at XA20L and at XB10 taxied out for takeoff. My batteries overheated, so I taxied back. I then spent the next 3 1/2 hours running between the plane and the phone to communicate with our maintenance people. I was not at an FBO and there was no place to situation on this cargo ramp, except in the plane but I didn't want to situation there because I was worried about carbon monoxide from the gpu which a mechanic had running while he worked on the plane. After literally standing around and running to the phone for almost 4 hours, I got into the plane to fly to cvg, the plane had its battery problems fixed. I was already tired, and under stress from watching the batteries very closely. I did not want a battery overheat in the air! About 1 1/2 hours into the flight, everything was normal and for the first time in 5 hours I was at peace. Now it was about XE15 central time when normally I would be sound asleep in the pilot's breakroom in cvg. It was very quiet on the radio. I had no copilot and no noise other than the droning sound of the turbine engines. I was so tired and it was so calm I just fell asleep. I estimate I slept for about 150 mi. I woke up and very quickly realized what had happened. I reestablished radio contact with center and proceeded to my destination without further incident. The main factors that contributed to my sleepiness were: flying when I would normally be asleep, having to stand around for hours while my plane was being worked on, and not having a copilot which I usually do. I also believe I may have had some carbon monoxide poisoning from the gpu, it ran for the whole time and it really, really polluted the area.

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Original NASA ASRS Text

Title: SINGLE PLT OF A TURBOPROP TWIN CARGO FLT FALLS ASLEEP FOR APPROX 150 MI AND WAKES UP AND CONTINUES TO DEST WITHOUT FURTHER INCIDENT.

Narrative: SHOWED UP AT MY PLANE AT XA20L AND AT XB10 TAXIED OUT FOR TKOF. MY BATTERIES OVERHEATED, SO I TAXIED BACK. I THEN SPENT THE NEXT 3 1/2 HRS RUNNING BTWN THE PLANE AND THE PHONE TO COMMUNICATE WITH OUR MAINT PEOPLE. I WAS NOT AT AN FBO AND THERE WAS NO PLACE TO SIT ON THIS CARGO RAMP, EXCEPT IN THE PLANE BUT I DIDN'T WANT TO SIT THERE BECAUSE I WAS WORRIED ABOUT CARBON MONOXIDE FROM THE GPU WHICH A MECH HAD RUNNING WHILE HE WORKED ON THE PLANE. AFTER LITERALLY STANDING AROUND AND RUNNING TO THE PHONE FOR ALMOST 4 HRS, I GOT INTO THE PLANE TO FLY TO CVG, THE PLANE HAD ITS BATTERY PROBS FIXED. I WAS ALREADY TIRED, AND UNDER STRESS FROM WATCHING THE BATTERIES VERY CLOSELY. I DID NOT WANT A BATTERY OVERHEAT IN THE AIR! ABOUT 1 1/2 HRS INTO THE FLT, EVERYTHING WAS NORMAL AND FOR THE FIRST TIME IN 5 HRS I WAS AT PEACE. NOW IT WAS ABOUT XE15 CENTRAL TIME WHEN NORMALLY I WOULD BE SOUND ASLEEP IN THE PLT'S BREAKROOM IN CVG. IT WAS VERY QUIET ON THE RADIO. I HAD NO COPLT AND NO NOISE OTHER THAN THE DRONING SOUND OF THE TURBINE ENGS. I WAS SO TIRED AND IT WAS SO CALM I JUST FELL ASLEEP. I ESTIMATE I SLEPT FOR ABOUT 150 MI. I WOKE UP AND VERY QUICKLY REALIZED WHAT HAD HAPPENED. I REESTABLISHED RADIO CONTACT WITH CTR AND PROCEEDED TO MY DEST WITHOUT FURTHER INCIDENT. THE MAIN FACTORS THAT CONTRIBUTED TO MY SLEEPINESS WERE: FLYING WHEN I WOULD NORMALLY BE ASLEEP, HAVING TO STAND AROUND FOR HRS WHILE MY PLANE WAS BEING WORKED ON, AND NOT HAVING A COPLT WHICH I USUALLY DO. I ALSO BELIEVE I MAY HAVE HAD SOME CARBON MONOXIDE POISONING FROM THE GPU, IT RAN FOR THE WHOLE TIME AND IT REALLY, REALLY POLLUTED THE AREA.

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.