Why do pilots shout "Propeller! Or Śmigło if they are Polish pilots in Poland :-)?

Question

Why do pilots shout "Propeller!" before starting an aeroplane engine, has anyone ever been irresponsible enough or a retard to approach the blades of a propeller, has it ever happened that someone was massacred by a propeller?

Answer 1

We yell: CLEAR!! 

so people in the area are aware of the danger. 

Surely people have been injured or killed by an airplane propellor.

Na pewno!

Answer 2

It’s short for “get out of the way of the f@cking propeller unless you want your head removed”!

Answer 3

There are many reported cases of people walking into rotating propellers and helicopter rotors.

American Airlines stewardess backed into a propeller and got a little behind in her work - LOL !!1

Answer 4

To warn people nearby that they are about to start the engine so that they stay away from the propeller area.  Getting hit in a head by a propeller will spoil their day.

Answer 5

Yes, many people have been hurt or killed by airplane propellers.

Answer 6

Whats gold and flys around Sydney Airport Jack Newtons watch.

Aussie golfer Jack Newton walked into a propeller lost his arm

Answer 7

Propellers are expensive - idiotfucks that walk into them not so much.