old planes

[Enver Pa�a]

 the fokker type WW1 planes have their machineguns just behind the propeller of the plane. what is the reason that makes the machine gun not break that propeller while it rotates?

[druiaghtagh]

 Because the guns are timed to fire through the gaps between the propelor blades

[Ewood27]

I've answered this once and it's vanished!  The original idea was to have deflector plates on the propeller blades so that any bullets hitting th blades would be, well, deflected.  The bullets tended to shoot the deflector plates off, though, then splinter the prop.

 

They also tried having the guns fired by a device worked by the propeller,, sot that the gun fired one round each time the system said the blades were out of the way.  That didn't work very well though.

 

The most widely used and most successful device was an interrupter gear which stopped the gun while the blades were in the way.  It worked well, but if it failed it still shot the prop off!

[SteveD]

That's a good question and one I've often wondered about.  It's difficult to imagine that bullets can be fired through the propeller without hitting the blades.

 

I'm curious; where are you from Enver Pa�a?  How do you pronounce that "�" in your name?

 

 

[ianess]

It wasn`t just Fokker aircraft..... planes of many nationalities had interrupter gearing which was obviously matched to propeller speed.......it must have been a brave man who first tested it in combat. 

[DickieD]

My Dad worked at the Sopwith factory in WW1 building Camels etc.. He told me about George Constantinesco who invented the interrupter gear. See http://fluid.power.net/fpn/const/const003.html

[Ewood27]

That page, DickieD, is what I would call a really comprehensive answer!  Fascinating.  Thanks for the reference.