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Cube roots for fuel consumption

Al AlohaDan · Oct 13, 2014 9:30pm
How does one handle cube roots for fuel problems? What calculator will the CG accept. Or will I have to review logerithem's and us tables from Bowditch?
Al AlohaDan · Oct 23, 2014 8:24pm
I found a solution. Assume your using the formula

New Fuel Consumption =F
Old Fuel Consumption = f
Old speed = s
New Speed = S

F = S^3 (* f)/ s^3

One would generally solve the above and end up with something that looks like S^3 = F s^3 / f

You can easily find s^3 by muliplying the number by itself 3 times.

So you will end up with say S^3 = 2460 or a number easily calculated.

You have an equation but don't have to find the root.

Just list the four answers separately:

A) 12.1 Then cube it again multiplying the number by itself 1771
B) 13.5 Cube is 2460 the right answer!
C) 14.6
D) 15.4

Good luck!