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quiet_man
08-05-2005, 06:59 AM
The biggest limit at current DM I see with structural parts, most important wings and body were the DM does not divide between struture and surface

IMHO
HE rounds are currently much to strong as their damage leads much to often to structural failure, HE should destroy the surface effecting air flow and maybe leading to structural failure when under critical load (high speed, heavy load)

AP rounds are to weak and to strong same time
an AP round should only do critical damage when hitting structure parts, if the energy is enough for penetration, the difference between 12,7/20/30/37 should only relative to hole size
at the moment heavy cannon AP rounds take of wings & tails by just touching, while light cannons/heavy MG rounds do no different damage even if they hit the "right" spot

I think alot of weapons discussions come in fact froms this.

my conclusion:
for BOB I would find it very important to introduce difference between Surface (mostly HE) and Structure (mostly AP) damage

quiet_man

Stigler_9_JG52
08-05-2005, 10:32 AM
I believe that's what they're attempting, and further, I believe the aircrafts' entire structure (even including struts and wing spacers) and components are going to somehow be taken into account.

If that's true, that should create new layers of complexity. Right now, I think every sim oversimplifies damage to some extent. I don't think the results are terribly far out of line, but there have been some areas of concern (e.g., how impotent the German 20mms were up until this latest patch, how [overly] often damage produced control cable cuts, etc.)

faustnik
08-05-2005, 10:40 AM
Originally posted by quiet_man:

for BOB I would find it very important to introduce difference between Surface (mostly HE) and Structure (mostly AP) damage


Quiet_man,

Looking at the complex internal structure models of the BoB development shots, there certainly is a good chance that this will happen. http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif

quiet_man
08-06-2005, 03:45 AM
Originally posted by faustnik:
...

Looking at the complex internal structure models of the BoB development shots, there certainly is a good chance that this will happen. http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif

I hope so, would be nice to get some confirmation http://forums.ubi.com/images/smilies/10.gif

quiet_man

quiet_man
08-06-2005, 04:02 AM
Originally posted by Stigler_9_JG52:
... (e.g., how impotent the German 20mms were up until this latest patch, how [overly] often damage produced control cable cuts, etc.)

the german 20mm are an good example!
- with mostly AP they were to weak, you needed to "hammer" one part of the target to get some effect
- with HE they are now to strong, cause they cause to much structural damage

worst examples are the cannons

e.g. Yak9K AP rounds destroy large parts of the target by just touching, while they should only do significant damage when directly hitting critical parts

german 30mm HE rounds do regularely structural damage I would not expect from them

quiet_man

Stigler_9_JG52
08-06-2005, 12:24 PM
What kind of damage do you "expect" from German 30mm? They could easily cut a fighter plane in two with one hit (the widely shown pic of a Spit rear fuse hit with a 30mm shell), or take a wing with one solid hit. Mostly because the blast would deform the area so badly as to render the entire machine unflyable.

Hoarmurath
08-06-2005, 01:15 PM
Its not a spit, its a bleinheim... Spits don't have dorsal turrets.

quiet_man
08-06-2005, 03:13 PM
Originally posted by Stigler_9_JG52:
What kind of damage do you "expect" from German 30mm? They could easily cut a fighter plane in two with one hit (the widely shown pic of a Spit rear fuse hit with a 30mm shell), or take a wing with one solid hit. Mostly because the blast would deform the area so badly as to render the entire machine unflyable.

yes, a "solid" 30mm hit should do critical damage but at the moment it doesn't matter how and where you hit

also a Spit wing might come off from 30mm, for some planes it was recommended to aim at wingroots, but for many not. If you watch guncams, taking of wings was not common practise against heavy bombers. 30mm punches big holes into the wing, maybe finaly forcing the bomber to drop his payload but not destroying the plane, this is also shown by german analysis that showed incinary ammo most effective against wings as the fire would melt structural parts making the wing come off after a few minutes

quiet_man

FritzGryphon
08-06-2005, 04:08 PM
The bombers do take many MK108 hits without suffering structural failure.

MK108 versus B17, B24 etc, cause of shootdown is usually fire. Unless you're one of those vultures, pouring shells into burning planes...

Kwiatos
08-07-2005, 04:27 AM
What about 37mm P-39 cannon? In 4.01 it seemed to be more weaker.

Kocur_
08-07-2005, 08:23 AM
quiet_man Posted :

"IMHO
HE rounds are currently much to strong as their damage leads much to often to structural failure, HE should destroy the surface effecting air flow and maybe leading to structural failure when under critical load (high speed, heavy load)"

"german 20mm are an good example!
- with HE they are now to strong, cause they cause to much structural damagethe"

Slow down plz!
Most of planes here have fuselages (some wings also Fw 190) built in semi monocoque technology: aluminium-most, wood-some, especially Lagg/La family. In that technologu fuselage of a plane in nothing more than a tube made of thin aluminium/plywood. We dont want that skin to collapse under pressure so it is stiffened with internal stiffeners and/or longerons mounted around bulkheads.
Those tubes strenght is based on the area of the tube: horizontal for side stresses, vertical for vertical stresses.
If you make a hole in that tube of a size the whole tube will be weakened in horizontal/vertical plane depending on where the hole is, proportionally to hole area.
In another words HE projectiles can cause structural failure not only due to aerodynamical reasons but for mechanical too. If fuselage structure was calculated to carry stress A and you remove part of that structure it will breake under much less stress. Also removal of part of the tube will result in removing part of entire tube stiffness. It all depends on total area of hole in structure and its position.
In conclusion: HE projectles make LARGE holes due to explosion of explosive material. They can cause mechanical failure of planes structure even in low speed, low g conditions.

In case of wings and control planes built in spars technology:
If HE round makes a hole in skin only: there is no almost no mechanical damage to entire structure, as skin does not carry stress in general. Problem will be with "new" aerodynamical properties of the structure at high speed.
If HE round explodes on, or even worse in a spar, well it all depends on weight of explosive inside of projectile, in simplification. Anyway there is good chance of critical damaging it and total structural failure.


"an AP round should only do critical damage when hitting structure parts, if the energy is enough for penetration, the difference between 12,7/20/30/37 should only relative to hole size"

Rgrt: its only hole size. If AP round penetrates semi-monocoque structure, damage is proportional to projectile cross section area. AP's are almost worthless UNLESS they hit somethng vital. In that case size matters, because its not caliber, i.e. diameter of projectile but area that matters. And it grows fast with increase of caliber! If leaks protected tank is hit with 12,7 mm AP the hole is 126,61mm^2 and protector might stop it. In case of 20mm AP hole is 314,00 mm^2, and thats significantly more.

In case of wings/control planes: it all depends on angle of shooting. In case of low angle you have a good chance of hitting spar.
12,7 mm AP the hole is 126,61mm^2,
20mm AP hole is 314,00 mm^2,
30mm AP hole is is 706,50 mm^2 (*)
37mm AP hole is 1074,66 mm^2,
45mm AP hole is 1589,62mm^2.
And again proportional part of spars strenght is removed.

* There was no MK-108 AP, belts were all filled with Minengeshoss rounds, with HUGE amount of explosive: 85g.
Also in five projectiles leaving MG-151/20 barrel two are 20mm Minengeschoss with 18 or 21g of explosive. In comparison British Hispano HE projectile consisted 7g of explosive.

quiet_man
08-09-2005, 01:43 PM
@Kocur_
"semi monocoque technology" is a good point
but I don't think it was used for wings(?)

and you have to admit that in that case a single 45mm AP round taking out the hole fuselage is not good? Also the HE round needs to hit the "right" spot to take out the structure, not anywhere.


in the game we have MK-108 AP rounds, were comes your information from?


about the DM, at the moment we have mostly all or nothing. Either the part hit is destroyed or not. The wing drop effect is a small improvement.
The new damage model should to support plane parts where damage leads to no structural failur but "only" negative "fligth" effects.

I'm looking forward to see if this is possible/will be done.

quiet_man

Kocur_
08-09-2005, 02:26 PM
"I don't think it was used for wings(?)"

Very rarely then. Vast majority were spars wings. The caisson technology was used in Fw190 wings for example.



"and you have to admit that in that case a single 45mm AP round taking out the hole fuselage is not good?"

I dont think its good indeed! But in case of 45mm HE I belive it could happen.



"Also the HE round needs to hit the "right" spot to take out the structure, not anywhere."

Thing are there are no "right" spots really. I mean entire perimeter carries stress. Id say it critical failure depends on size of that "tube" part removed. Definately single 20mm HE couldnt weaken structure enough to cause this. It'd take many 20mm HE explosions to make enough damage. It could be very different in case of 30mm or 37mm HE.



"in the game we have MK-108 AP rounds, were comes your information from?"


http://www.geocities.com/CapeCanaveral/Hangar/8217/fgun/fgun-am.html

AP's in case of MK108 dont make much sense, because of relatively low muzzle velocity.
MK101 and MK103 are very different story.



"The new damage model should to support plane parts where damage leads to no structural failur but "only" negative "fligth" effects."


At least partially its already there. Flying Fw190 usually includes some long running with enemy at 6. I noticed that after receiving some hits your maximum speed decreases. Most probably it works that way on others too, but on other planes usually you manouver one way or another rather than run straight long enough to reach maximum speed, so you dont have much occasion to notice that