Recruitable Unit Rebalance Version 7.51 Released.

[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.

[Arralen]

energetic efficiency of the bow
I'm not confusing it with the aerodynamic efficiency of the arrow. In fact, I thought to leave it out of the discussion, but I found a nice comparison which should make it easy to understand: "Barrel Length" .. the distance over which the missile is accelerated by propelling forces.
With a X-/bow, it roughly equates to the length of the arrow minus some "overhead", which is 80cm with the Longbow and 25cm with the X-bow. Equations are most likely non-linear ...

examples: (from Payne-Gallway, actually) 85 g bolt shot 420 m from a 550 kg pull medieval crossbow. Longbows attained lengths of ~275 m. Article authors cite another historian claiming 2x pull weight xbows were common, fwiw.

That's shurely a 55kg-Xbow. And 110kg-Xbows where shurely not common before 1475.(Steel Xbows in general date from 1350 and later).
And think about the reloading time: I would rate such a Xbow as a last try to keep up with a)the very heavy armors and b)firearms. And it shurely would have been used in siege warfare only - much to heavy to use it in the field...


aerodynamic efficiency
Can you scan & email me that wind tunnel results? Or give me a link? Think there's some fault in those numbers or the interpretation ...
E.g. using 80 instead of 60 m/s may have greater impact on the results than one would estimate because of special aerodynimc effects (boundary transition etc.)
Because of the differences in energetic efficiency of Long- vs. Xbow, I doubt both sorts of missiles start with the same "muzzle velocity".
=> Normally, something long&slender has always less drag than something thick&short, as long as it points into the direction of flight.

Furthermore, there's a mixup:
A longbow's efficient range is roughly equal to it's maximum range, because of the energy-storing effect of the ballistic trajectory and the lift-generating effect of the long arrow. (Similar to the lift effects on modern olympic throwing spears)
A X-bow bolt, because of the higher drag at high velocities, loses too much energy before it can store as potential energy, respc. loses much more of it's velocity within the first meters of flight.


volume/mass fire
You can fire a X-bow ballistically. But
load time is way to high for volume fire. A longbowmen can fire his 12 arrows within a minute. It takes a minute to fire a heavy crossbow and reload it...
So apart from the initial volley, there wouldn't be any volume to speak of. But without volume, you'll actually have to aim for a target ...

pre-historic "longbows"
Where long bows, but not longbows in a strict sense:
"At least two Neolithic longbows have been found in Britain. One was found in Somerset. It was identified as Neolithic by radiocarbon dating in the 1950s, much to the consternation of some archaeologists at the time. A second was found in southern Scotland at Rotten Bottom. It was made of yew and dates to between 4040 and 3640 BC. A reconstructed bow had a draw-weight of about 23 kg (50 lbf, 220 N) and a range of 50 to 55 metres.


addendum
found it in your post:
From Hardy: (velocity and range, 70 lb bow)
Lozenge Bodkin 46.5 m/sec 180 yd max (sigh, let's mix units)
Long Bodkin 43.6 m/sec 170 yd
Broadhead 38.7 m/sec 150 yd
extrapolation to 150 lbs, still Hardy, ranges should be ~300 yds

But 70lbs = 31,75 kg, which is on the lower range for a longbow, 100lbs (45kg) or even more seemingly where common. Range will not scale linearily, though.
But as you can see from the numbers above, "muzzle velocity" wasn't anywhere near 80 m/s but maybe 55m/s at best. Aerodynamic effects could be quite different ...

[wombatsSAR]

Arralen said:
energetic efficiency of the bow
I'm not confusing it with the aerodynamic efficiency of the arrow. In fact, I thought to leave it out of the discussion, but I found a nice comparison which should make it easy to understand: "Barrel Length" .. the distance over which the missile is accelerated by propelling forces.

Which is only relevant if the applied force is the same. It is much, much higher in the xbow, hence the need for very stout bolts.

With a X-/bow, it roughly equates to the length of the arrow minus some "overhead", which is 80cm with the Longbow and 25cm with the X-bow. Equations are most likely non-linear ...

Yes, they are. Acceleration is a squared term. Friction is as well. Your point?

That's shurely a 55kg-Xbow. And 110kg-Xbows where shurely not common before 1475.(Steel Xbows in general date from 1350 and later).
And think about the reloading time: I would rate such a Xbow as a last try to keep up with a)the very heavy armors and b)firearms. And it shurely would have been used in siege warfare only - much to heavy to use it in the field...

By this logic, a 55 kg draw weight xbow can out shoot a 90 kg draw weight longbow. That's aerodynamic efficiency far beyond what's been measured and makes the longbow much less efficient than the crossbow.

I'm skipping the rest of your comments because they are based upon similar logic.

[wombatsSAR]

The whole reason for me posting was to weigh in was because various comments that desired a sim approach. I felt that some of the suggestions for the sim side were not accurately describing various phenomena and I wanted to add information from various knowledgable sources. I am not an expert on these subjects but I am moderately well-read.

Sim: xbows blow away everything else in terms of sheer hitting power. At least the steel variety. The pre-steel ones score over the traditional bows in being MUCH easier to train peasants to an adequate level of skill. They are cheaper to stock and the bows are more durable than regular bows. Reload rates sucked but then, if you kill them first, you don't have to parry.

Sim: pointy things - all of the pointy weapons are armor piercing in effect. They plant an enormous overpressure on the armor causing a point failure. The longbow and composite bows had enough force to let them pierce plate when using properly designed arrowheads. These bodkin points did a good job at piercing various armors but were inferior to a broadhead for inflicting wounds (we're neglecting sepsis here). The xbow did it by sheer force. Afaict, there were no bodkin point quarrels. One design sufficed for all applications.

Thus, my recommendations for a sim that longbowmen and composite bowmen have higher resource costs to reflect their long training times. Their projectiles should be AP but of low value to simulate the fact that the resulting wounds were of lesser severity. Even short bows should be AP but without the draw weight behind them, they couldn't do all that much. Spears and lances should be AP when used in charges. By precise definition, so should spears in static melee but the impact velocities probably don't make it worth defining that way, at least not for human wielders.

One obvious "flaw", as it were, is that the battlefield is so short that the effective ranges of the various missile weapons are ... modififed. This truncation results in the combatants starting very close together resulting in the effectiveness of bow fire being compromised. This could be hacked but I'm not sure if the game would support that???

[BigDaddy]

wombatsSAR said:

. . .Sim: xbows blow away everything else in terms of sheer hitting power. At least the steel variety. . .

I looked into this for quite some time to prove that medieval x-bow where more powerful than medieval longbows. However, I found that that wasn't the case. Because of the inferior engineering and material medieval x-bow where made from, they where limited to a very short draw length, and the quarrel never even remotely approached its maximum velocity. Because of the respective weight of the missles, both end up being nearly the same. The difference from my historical research, was that longbowmen where actual troops, who carried swords, wore light armor, and could really fight. They fired faster, and hit more. A x-bowman, was just a conscript with an x-bow.

Today's x-bow have an incredible draw length. The bow goes from nearly straight to "V" shaped. This increased draw lenght allows the projectile to reach incredible velocities. Far superior even to compound bows. That was not the case in medieval times.