Re: Which weather station, Pocket PC, and Balistic Program?
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Also does this program account for gryrscopic lateral and vertical movements associated with a right or left twist barrel (Precession, Magnus, Bernoulli's, Coning, Yaw of Repose) or do you have to figure that out on your own?
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For any program to account for these effects, the method used must be a numerical 6-DOF, and of course, you must have at hand the ( a considerable number ) the aerodynamics coefficients for YOUR particular bullet.
( Total angle of attack in Radians, Axial force coefficient, Normal force coefficient derivative (1/rad), Overturning moment coefficient derivative (1/rad), Magnus moment coefficient derivative (1/rad), Pitch damping moment coefficient, Spin decay roll moment coefficient )
Be aware this approach has two main issues.
One, you need such a kind of facility ( plus the money and engineers ) to obtain the coefficients that's only available to the goverment's labs unless you can afford it...then, the 6-DOF needs a LOT of computer resources to yield a good solution, which absolutely precludes it to be used on a PDA.
Same problem was faced by the USAF years ago, and they turned to a modified Siacci's solution.
Moreover, I really doubt that you need to account for these gyroscopic and viscous effects except you are going to shoot from a moving vehicle at high speed, while at the same time trying to hit a target a couple of miles away.
However if you insist on having these effects accounted for you can precalculate them ( again with a 6-DOF model ) and then incorporate its values to your trajectory.
In short, for some of the reasons aforementioned, today, even the military for some cases, uses analytical closed-form solutions. Of course, discussing which is best is another question! since I have my own preferences. [img]/ubbthreads/images/graemlins/grin.gif[/img]