Hi Darrel,

Isn't it wonderful when we try to improve the accuracy with about half a ppm .... and the world has hardly descided how long a nautical mile really is. I got "1 knot = 1.15078030303 mph" from http://www.geocities.com/TheTropics/...311/ktmph.html , but after doing a little more digging around, i now agree with you. It shows that you can't really trust anything you find on the net.

BTW, i really like the way you do the rounding, i can imagine that beeing speedy in assembler ....... i just might steal it sometime ;-)

Just to be a pain, i'll show how i'd do this calculation with rounding(and adding that extra little accuracy). Perhaps someone will find it useful.

Dec_speed = ((Dec_speed */ 2946) + 5) / 10

It's probably a little slower than your method since it involves a division.

/Ingvar