- Thread starter Dust
- Start date

Orion, et al -

So, if I figure it correctly, I have a prop 74" diameter, or 6.167 ft.

At 2,400 rpm (120 mph, say), I get 774.4 fps for the tip rotation speed, plus 176 fps for the forward airspeed. Squared, added, and then square root gives me a corrected tip speed of 794 fps.

Did my basic math add up right?