Narrative:

A passenger entered the cockpit to sit in the copilot seat and turned off all electrical power in the aircraft by hitting the overhead electrical panel with his head. The EFIS for both pilots went off; the autopilot went off; and the engine instruments went off. I then had to wait for everything to go through their startup diagnostics and do the autopilot test. I had to fly raw data NORDO for several minutes with just a battery powered standby 2 in attitude gyro. The controller apparently never noticed. I don't really know if I had an altitude deviation as too much was happening at once but I don't think I did.#1 they could use a simple guard to recess the switches; a piece of clear plastic with slots cut in it so the tip of the switch is flush with the surface.#2 garmin radios will delay shutdown a few seconds and ask if you really want to shut down - it would be nice if the electrical system did that.#3 I am a pilatus instructor [and] we see and hear of this all the time. It's something that is lived with but is a characteristic of what I call high tech 'airbussy' type planes. I am rated in many turbine airplanes and looks can be deceiving; the pilatus is the most complicated I fly. On the surface it is simple to operate but is [actually] very complex and sometimes has penalties for that. A large portion of owners are lower time owner pilots and don't grasp all the automation issues.

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Original NASA ASRS Text

Title: A PC12 Captain reported losing all EFIS data for several minutes after a passenger accidentally turned off power to the system.

Narrative: A passenger entered the cockpit to sit in the copilot seat and turned off all electrical power in the aircraft by hitting the overhead electrical panel with his head. The EFIS for both pilots went off; the autopilot went off; and the engine instruments went off. I then had to wait for everything to go through their startup diagnostics and do the autopilot test. I had to fly raw data NORDO for several minutes with just a battery powered standby 2 in attitude gyro. The Controller apparently never noticed. I don't really know if I had an altitude deviation as too much was happening at once but I don't think I did.#1 They could use a simple guard to recess the switches; a piece of clear plastic with slots cut in it so the tip of the switch is flush with the surface.#2 Garmin radios will delay shutdown a few seconds and ask if you really want to shut down - it would be nice if the electrical system did that.#3 I am a Pilatus instructor [and] we see and hear of this all the time. It's something that is lived with but is a characteristic of what I call high tech 'airbussy' type planes. I am rated in many turbine airplanes and looks can be deceiving; the Pilatus is the most complicated I fly. On the surface it is simple to operate but is [actually] very complex and sometimes has penalties for that. A large portion of owners are lower time owner pilots and don't grasp all the automation issues.

Data retrieved from NASA's ASRS site as of July 2013 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.