Naval History Forums

@Bill Jurens Many thanks. Without modifying anything in the present code but the shell mass, velocity and frontal area to these respective values (870.91 kg, 746.95 m/s, 0.113048 m²), ie; your provided values converted to SI, I get; 25,762 meters range (28,166 yards) 29.5º impact angle 453.2 m/s fin...

@tommy303;

All good reading, thanks!

PS: Isn't that Seydlitz's motif, the BC of BC's, if I am not mistaken?

Thanks, delcyros. I just had a quick look at the source code, but have not run the program (yet) as I am on Linux. It is interesting, though there are three main differences (apart from the fact that his has armor penetration calculations); the air density is calculated by a constant formula, and I ...

Okay, with the data tweaked for the USN 16" gun, at a projectile mass of 1224.7 kg, a muzzle velocity of 762.2 m/s, the air density according to ISA per altitude (interpolated off an array table), and Mach number off ISA temperatures, starting at 340.278 m/s, with a decrease of 0.61 m/s for eve...

Oh, I can cheat now. A table on this page shows some curious Cd behavior of a "bullet" that approximates what my "experimentation" has been revealing. To simplify, I can map these points to velocity in Mach, calculate the Mach speed variation at different altitudes, and interpola...

<Chuckle> One small step at a time! This is beginning to look like a good thesis project for mega-geek (with all due respect and hats off to the species) doing a university course in kinetic physics, not a middle aged chap with a distant interest in the subject and a hobby of fiddling with C++ every...

Thanks for that detail, Mostlyharmless. I was already thinking of working that variable into the computations, as experimenting subsequently with angles of elevation revealed that the shell could easily be lofted to over 11 km altitude, even with higher drag coefficients (more on that in a moment), ...

Well, well! Thanks for those links, they are very helpful. It seems, by the results, that my physics were about right. The main "problem", if I can call it that, is that the coefficient of drag was a bit low at 0.22. Values between 0.25 to 0.27 hit it on the money.

Thanks again!

Hello again. I am here with some questions, as I think there will probably be someone here who knows this matter. The subject is (roughly) the venerable Royal Navy 15" gun. What altitude did the shell reach at the top of its loft, if fired at about a 22º elevation angle, for example? What might...

Hello again, and thank you for that welcome! Bgile, yes I do have Action Stations! running on a 64 bit system, through DosBox, and that on Linux Debian 6, so fortunately my favorite simulation proved to be quite adaptable. I only ever played a demo of Fighting Steel, and quite a while back, but I re...

Hello to all, My first post. I have been a naval warfare and history self taught "student" for years. I am not as obsessed with the subject now as much as I used to be once, but maintain a keen interest in the subject, and still hold that the best reading is sitting down with a book on any...