[William May]

Piston powered aircraft have a couple things that make them more dangerous than other machines. (besides flying)
#1 is that the ignition system is powered off of engine movement, so if you move the propeller, and the magnetos are live, the engine can fire and start. To make it easier to start, most magnetos have what is called an "impulse coupling" which winds up a spring so when the engine is moving slowly, such as in starting, it will deliver a hefty spark and get the engine running. Once the engine fires up, this spring is out of the picture, and everything is normal.
Another thing is that, being magneto fired, you don't need a battery or other electrical system to start the engine. The ONLY way to shut off the ignition system is to interrupt what is known as the "P-Lead" which determines if the magneto is hot or not. Now, if you have a short in the "P-lead", then you have a LIVE engine that is READY TO FIRE as soon as the propeller is moved, and it can be from 4" movement down to just moving the propeller 1/16" of an inch. If the impulse coupling is right on the edge, just touching the propeller is enough to make the engine kick over with a live ignition system.
As an airplane mechanic, I have hand-propped aircraft many times, from a Cessna 140 up to a Beech 18 with a R985 Radial Engine. You can bet I treat them with respect.
I don't care if the battery is dead and the tires are flat on the airplane, you can just touch the propeller and instantly be facing a slice and dice machine. It looks like he was troubleshooting some type of problem, and his ignition is either on, or the "P-lead" is shorted. If they investigate and know what they are looking for, that is probably what they will find. (Even if the ignition is off, and the key is removed, if the "P-lead" is hot, then the engine will run)
That is actually one of the checks you make before takeoff, when you do your mag check. You turn the switch momentarily to OFF to make sure the engine will really stop.
What do you do if you have a hot "P-lead"? Just go to idle cutoff on the fuel, and you run the engine out of gas.

[CREGGERSTEVE]

I bet the throttle was wide open and when he turned the prop by hand, the plane moved forward and hit him.

[CREGGERSTEVE]

Sorry William May, I did not read your post before I put my 2 cents in, otherwise I would not have posted.

[murofhsirgo]

did anyone tell that pilot that that thingy spins round and round real fast?

[Razorhead]

Wow, looks like a Leviathan from "Supernatural".

[JoseQuinones]

This is why my dad always told me to disconnect the spark plug before cleaning the dried grass off the mower blade. One quick twist, and it would start running and potentially cut off a hand. Same principle applies here - when you work on an airplane engine, always shut off the fuel valve. A friend who is an airplane mechanic told me that you can never rely on the brake alone to keep you safe. You have to bleed the fuel line to be really sure. "No pasa chispa, no pasa mierda," he tells me. (No spark happens, no sh*t happens.)

[ousoonerchic]

Holy shit

[vicksvaporub]

[XxMutilatedxX]

OH SNAP!

[kilyurselph]

Face Off!!! - Ever see that stupid ass movie, Face Off? With Xenu worshiping Scientologist Tool John Travolta, and the piece of wood that pretends to be an actor named Nicholas Cage? Terrible, just terrible!