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Old July 11th 08, 09:13 PM posted to rec.aviation.piloting
Maxwell[_2_]
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Default Prop angle of attack vs age


"sid" wrote in message
...

Not knowing much about props, what do you mean by "... they are each
2 inches of pitch apart." ?
I thought props were measured in dia. and angle ?

Thanks

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A propellers angle or pitch is expressed in inches. Theoretically, a 24"
pitch prop has an angle that would travel 24" forward with each revolution,
at zero angle of attack. The smaller the number, the flatter the prop.

If that seems confusing, consider a right trangle. If the circumference of
the propeller arc at any given station is the base, the pitch is the height,
and the resulting angle is the pitch angle for that station. That's why
props have less angle at the tip, than at the root. Theoretically, it keeps
the entire lenght of the blade working at the same angle of attack.

Thus climb props are flatter or less pitch, and cruise props have more.