Originally Posted by
dundem
Or we could use 2*pi*r= the circumfrence of a circle. pi=22/7 r=whatever the arc is (13dme in the case above). Since an arc is a part of a circle, multiply above formula by the degrees in the arc over 360. This could be done on paper in maybe 20-30 secs and they may be impressed.
I hope my math is right as I haven't done a math course in years.
Wow, good luck with that! Whats so hard about estimating to make the mental math easy? Look folks 13DME is pretty close to 12DME, right? At 12 DME each degree of arc is roughly 1/5 of a mile (60/12). Divide the number of degrees to arc by 5 (70/5=14) and boom, i just flew 14 miles along the arc. No paper or calculator required. Sheesh, yall like to make things complicated, dontcha!
And no, they wouldn't be impressed. If a kid whipped that out when I used to give checkrides (Not that I would, its a stupid question. Who cares how many miles you flew along an arc?) I'd tell him thats how a mathematician would figure it out, now how would a pilot do it?