Recruitable Unit Rebalance Version 7.51 Released.

[Evil Dave]

Saber Cherry said:
Firing a crossbow ballistically is like firing a handgun ballistically - possible, but never done (aside from corrections of a few feet of drop, generally calculated by the scope) since you only have control over a single factor, angle. At least, that's how it would seem to me...

but that's how rifles and (some) artillery work today.

I'm particularly surprised at the terrible arrowodynamics (get it? A pun!). This might be mitigated a bit by firing in high arcs, thus storing some energy as potential (immune to drag) for much of the flight, as opposed to firing flat, where the energy is always kinetic (and thus vulnerable to energy loss from drag, proportional to v^2 IIRC).

you know one statement of the three laws of thermodynamics is "you can't win, you can't break even, and you can't get out of the game"? same with arching flight: yes, you can reduce *instanteous* drag with the high trajectory, but the time of flight is much longer than a flat trajectory, so drag works *longer*. i'd have to dig up the drag-corrected ballistic equation to figure out what the actual numbers are.

there's also the little problem that for fin-stabilized projectiles, their ability to stay pointed in the right direction goes up as v^2 also, since that term is in the equation for lift. so, there goes their precision.

[Saber Cherry]

Evil Dave said:

but that's how rifles and (some) artillery work today.

I know, field artillery is like that, but they do a bunch of calculations before firing... and rifles have adjustable scopes that account for drop over distance... and medieval xbowmen had neither calculators nor scopes. The only crossbow I've ever seen with a scope was in Deus Ex, and I put it there myself

I think it would be very hard to fire a crossbow accurately with more than a minor (<5 degrees) arc... and any arc-firing requires more training than direct firing, which would defeat the point of cheaply raising masses of untrained crossbowmen. Assuming, of course, that crossbows were used by cheap masses of poorly trained soldiers, which could be another false premise on my part.

Your point on the longer trajectory negating a lower velocity is interesting... it would take several complex integrals to figure out how much energy ends up being saved, if any, by firing at a 30-degree angle or so. It would be much simpler to model in Excel (in .01 second intervals), given the drag formula. I did something like that once, to find the ideal angle to launch a water balloon for max distance, but I have a pretty poor memory...

[Evil Dave]

Saber Cherry said:
I think it would be very hard to fire a crossbow accurately with more than a minor (<5 degrees) arc... and any arc-firing requires more training than direct firing, which would defeat the point of cheaply raising masses of untrained crossbowmen. Assuming, of course, that crossbows were used by cheap masses of poorly trained soldiers, which could be another false premise on my part.

i imagine if you had to train levies to fire crossbows ballistically, you'd do it the way the napoleonics did with muskets: drill a few angles for likely ranges (maximum, half-max, short) and figure that will do well enuf.

[The_Tauren13]

I think gameplay should be way more important than realism. This is a fantasy game, after all.

[Evil Dave]

The_Tauren13 said:
I think gameplay should be way more important than realism. This is a fantasy game, after all.

yup. it's mighty hard to realistically model gods on the battlefield.

the main reason for bringing up realism is folks were asking how weapons "should" work. but another reason is that it provides justification for changing game balance. for example, if you agree with wombats' idea that many pointy weapons should be armor piercing, SCs become relatively less powerful and some regular units become relatively more powerful.

[wombatsSAR]

Sabercherry: "arrowdynamics"

Thanks, great pun
I used to have:

"Incorrigable punster.
Please do not incorrige."

as my sig.

[wombatsSAR]

One last post before my brain explodes.

Arralen, you might be confusing the aerodynamic efficiency of the arrow with the energetic efficiency of the bow. Hardy's book has values of around 80%+ for the longbow. Iirc, modern, compound composite bows are closer to 90%+, while the crossbow is much lower but I can't find any relavent numbers right now. One rather biased source put it at 10% but that's too low considering extent numbers for ranges and projectiles. Xbows may have been capable of storing lots of energy but they really didn't deliver any where near all of it to the projectile.