I was standing by a service rig a few years ago, up by the engine. The crew was laying down pipe, so every connection the operator would rev the engine full throttle to run the power tongs. Fuckin fan went off like a bomb! Shot plastic blades every where, somehow the shrapnel missed me entirely, but blew threw the shroud, rad , and air to air. Pieces of plastic straight through aluminum!
I bought a stock 454 out of a wrecked 77 one ton Chevy and put it in a 79 shortbed 4x4. Got it all together and running, was standin with my kness on the radiator support, reached over and wacked the throttle and the fan came off and hit my elbow and broke it. I damn near passed out! Got down and shut the truck off and went in the house to get the ol lady to take me to the ER. Here the waterpump shaft mustve got hit in the wreck and it was cracked. When the shaft broke, the hub, pulley, heavy clutch fan and all came apart, walked right out of the belt and went straight up in a hurry!
A buddy of mine in high school had a Trans Am. Going down the road, the water pump shaft broke, and the stock steel fan cut a huge gash up through the hood. Phucked up his hoses, radiator, and the hood. Scary shit!!