SOH-CAH-TOA will work to find distance in whatever units you are using. I wish I could use whiteboard here to show you, it will work on any triangle that is a right triangle as Joe said. You will use the tan function as well, that is because you know the angle and you know the lenght of the adjacent, you want the length of the opposite. Trust me on this though this is way way way more complicated than using the degrees of deflection because you will end up with having to draw an arc equal to the radius then using calculus to figure the arc length to just draw a triangle into the circle cause your numbers will be very small. Degrees are precise and accurate. grab a protractor if you don't have anything else to measure angles of deflection.

I know reading what I said is as confusing as all get out but somewhere in there if you can picture a right triangle and then picture the sides as opposite and adjacent and hypotenuse(the longest side) it will make some sense.

Eric