what is the difference between propeller pitch and chord length?
In: 1
Chord is a line through the middle.
Make your hand into a C shape, imagine a line cutting it in half. That is the chord line of your hand.
This applies to any airfoil. Wings, propellers, your hand in this example!
Now take that hand example and look at how long that line is. That line is the Chord length.
Now that you know that,
The chord length is the length from the leading edge to the trailing edge.
This is needed for stuff such as angle of attach, and propeller pitch!
Now for
Propeller pitch.
Propeller pitch is the angle of the propeller to the relative wind.. what does that mean?
Well it means that you need to go for a drive and put your arm out the window!
Feel the wind? That’s the relative wind.. now for the pitch.. when your hand is flat you have 0 resistance. That’s a pitch so low it’s called feathered.
Turn it slightly, there’s a little resistance. That’s a low pitch propeller. There isn’t that much of a difference between the relative wind of the car, and your hand..
Now put your hand flat out.. there’s tons of resistance. That’s a high angle..
Aircraft use this to balance how much air they’re pulling. It’s called a constant speed or Variable pitch propeller.
There are also fixed props which don’t move at all. Pretty much a Lego propeller but big.. or one made of wood!
Source: I’m a licensed aircraft mechanic. Source 2: google FAA H-8083-32A which is the faa powerplant book for mechanics. It’s free and there’s an entire chapter on propellers.
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