Is thrust linearly related to propeller-pitch?

[Jarfi]

Simple question, Given a constant speed, is the thrust of a propeller linearly related to it's pitch?

 

[rbelli1]

No.

Think about the thrust at 0 and 90 degrees.

BoB

 

[Jarfi]

No.

Think about the thrust at 0 and 90 degrees.

BoB

What exactly is the relationship then?

 

[CWatters]

First of all what do you mean by "constant speed"? On a plane flying at a constant speed drag and thrust are usually constant and equal to each other. If you vary the pitch and as a result you change thrust then speed will usually change.

A prop blade is essentially a wing. Thrust from a prop is roughly equivalent to lift from a wing. Perhaps take a look at graphs of lift vs angle of attack. The shape of the curve depends on the wing section. It might be reasonably linear over a narrow range of angles...

Just the first one I could google. I think it's a model aircraft wing section...

 

[rcgldr]

If you search online for "static thrust calculator", most of them don't have an input parameter for pitch, stating that pitch (within reason) doesn't make much difference in a static situation, due to limitations of the induced flow in a static situation.

The pitch comes into play when the prop is moving forwards. As air speed increase, a greater amount of pitch can be used on aircraft with adjustable pitch.