Propeller weight distribution

[twakeley]

All,

I'm trying to resolve some forces due to the loss of a propeller blade. I have the total weight but am unsure of the weight of each blade. Is there a general rule of thumb for weight distribution between the blades and hub of a propeller? Does the proportion change due to the size of the prop? I'm thinking 40% hub and 60% blades as a starting point.. ideas?

Trevor

[Olav]

I don't know of any rule of thumb but it should be fairly easy to determine the weight of the hub by measuring/calculating its volume and multiplying it with the material density. The difference between the total weight and that of the hub then logically is the weight of the blades.

The proportion between hub and blade weight is constant unless there is a non-linearity between prop diameter and hub size, i.e. a bigger propeller may get away with a proportionally smaller hub than one with lower dia.

[daiquiri]

Think of Archimedes and you'll figure out how to calculate a single blade weight. ;)