Re: Calculating dihedral angle

Lyman Slack wrote:
Seems to me someone said for lower angles, 1" @ 60" roughly equals 1 degree.(???) Like in the case of your wing, 2" up @24" out would give you roughly 5 degrees. (2/24=x/60=5) Of course, you could get a cheap protractor and draw it out :-)

Don't have to ..for angles under 5 degrees or so the tan of the angle is almost* the sine of the angle is almost the arc of the angle..

The mathematical exprssion is

As theta tends to zero, sin(theta) tends to tan (theta) tends to (theta)

One radian is 57.3** degrees roughly, so one inch on 57.3 inches is a degree.


* to within 5% or so. Whose counting?

** 360/2*pi..
.

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