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Comparing HMG Damage, and issues with .50 cals


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The perennial argument of those that downplay the concerns about .50 cal damage is that "they should not cause aerodynamic damage because they pass straight through the target". This business with the ricocheting of bullets doesn't make much sense if that claim is to be believed. If something is being deflected either inside the wing structure (striking a spar for instance), then it should be causing more structural damage and larger exit holes. If it's ricocheting off of the wing surface (even less realistic), then it would be deforming the wing surface. No matter how you take this information, the .50s are underperforming in their current state.

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Roland_HUNter
On 1/24/2021 at 4:32 PM, NIK14 said:

 

 

I love the way you hint to the people running the MP servers to put in a limitation for the availability for allied API by saying this...

 

Should we really go down that path? From all the books I've read about this, it's clear that by the beginning of 1944 I believe the axis had a shortage on pretty much everything....whilst the allies had an abundance of supplies?

 

Try harder...

1944 Germans had shortage of everything?
Boi Ihope you know, the germans has no fuel problem until 1944 april, when 1 yes 1 american suggested to bomb the syntetic refineries. (luftwaffe had no fuel problem until 1945)

 DefeatGAF23.jpg 

Source:http://www.allworldwars.com/The Defeat of the German Air Force.html

And the germans produced the MOST in 1944: Most tank, planes everything.
Example: They produced 300-500 BF-109 in 1943/month.
In 1944 they increased it to ~1200/month. Oh and they distributed the big factories into little manufactures. 4-5 big factory into 700 little manufacture.
Bf-109:
1943:6418,
1944:14,152
They produced 1500-2000 Panzer IV in 1943, in 1944-1945 they produced 5500. Panther: 1943: 1200, 1944-45:5000.

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34 minutes ago, -[HRAF]Roland_HUNter said:

1944 Germans had shortage of everything?
Boi Ihope you know, the germans has no fuel problem until 1944 april, when 1 yes 1 american suggested to bomb the syntetic refineries.
And the germans produced the MOST in 1944: Most tank, planes everything.
Example: They produced 300-500 BF-109 in 1943/month.
In 1944 they increased it to ~1200/month. Oh and they distributed the big factories into little manufactures. 4-5 big factory into 700 little manufacture.
Bf-109:
1943:6418,
1944:14,152
They produced 1500-2000 Panzer IV in 1943, in 1944-1945 they produced 5500. Panther: 1943: 1200, 1944-45:5000.

now wehr is my bingo card...i thought i had it around here somewhere...

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VBF-12_KW
47 minutes ago, -[HRAF]Roland_HUNter said:

1944 Germans had shortage of everything?
Boi Ihope you know, the germans has no fuel problem until 1944 april, when 1 yes 1 american suggested to bomb the syntetic refineries.
And the germans produced the MOST in 1944: Most tank, planes everything.
Example: They produced 300-500 BF-109 in 1943/month.
In 1944 they increased it to ~1200/month. Oh and they distributed the big factories into little manufactures. 4-5 big factory into 700 little manufacture.
Bf-109:
1943:6418,
1944:14,152
They produced 1500-2000 Panzer IV in 1943, in 1944-1945 they produced 5500. Panther: 1943: 1200, 1944-45:5000.

Wildly off topic, but I can’t help but point out that those production gains were achieved by:


ceasing production of nearly every aircraft except the 109, 190 and 262

 

pressing huge amounts of slave labor into service, resulting in an aviation work force similar in size to that of the US (for a fraction of the output)

 

fudging their numbers to the tune of 8000 fighters in order to keep Speer in Hitler’s good graces

 

cutting every corner possible in actual production, resulting in fighters that were often 20+ mph slower than their specifications, if they even ran or flew at all

 

But hey, the numbers looked good on paper.

 

And those stupid Americans.  They just put together a target list of potentially vital choke points in the German economy with the aid of businessmen who had worked in Germany extensively before the war.  And then once they reached a point of being able to actually bomb those targets regularly and observe the results, it took an entire four months to arrive at the optimal targets(fuel and rail infrastructure) to cripple German industry (whose production started dropping off a cliff in September, before any Allied soldier had set foot in the Reich).  What a bunch of idiots.

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unreasonable
Just now, QB.Creep said:

No matter how you take this information, the .50s are underperforming in their current state.

 

Under performing relative to what? The physical reality of .50 cal AP ammunition vs aeroplane wings? The game's 13mm HE?  Or gamer desire that a burst of .50 cals should cripple a target in MP?  You cannot agree on the solution to a problem if you have inconsistent definitions of what the problem actually is.

 

The OP points out a difference in the ratios between the number of shots required to reach level 3 damage - ie the most severe level of surface damage possible consistent with the plane still being flyable. I think everyone commenting so far finds the ratio excessive, but they often do not say why. 

 

Suppose you thought 5:1 is reasonable.  You can adjust the ratio by adjusting either, or both, of the quantities.   20:1 can go to 20:4  or 5:1  or 10:2

Clearly these require different adjustments to the model, not all of which will make  .50 cal AP capable of noticeably slowing down a target fighter by increasing it's drag.

 

If the just ratio of modelled surface damage is "wrong", is that because the damage from 13mm HE is too high, the damage from .50 cal too low, or both?

 

Or are you simply asking for a .50 cal API shell to be modelled, in addition to the current .50 cal AP?

 

FWIIW my own views are that the .50 cal AP surface damage is actually plausible, but it would not bother me if it was ~doubled. The 13mm HE I find wildly implausible. API is not modelled but should be,  not as a bodge on all .50 cal AP,  but explicitly, as should other incendiaries for other gun types.

 

Then you would have a .50 cal AP bullet with similar characteristics to today's, a 13mm HE bullet with considerably reduced surface effects (both quantity and spread), and a .50 cal API shell with performance somewhere in between.  I am happy to adjust any of those views based on evidence of what the shell types actually did to real planes.

 

Solutions I would regard as unacceptable in a simulation would be to make .50 cal AP behave like a bullet with a significant CE load (API), just in order to appease an MP faction that is frustrated by certain aspects of their targets' flight behaviour. 

 

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Yak_Panther

It’s not just the .50’s cals that are effected by the ricochet issue though. It’s all AP ammo. 20 mm ap is also largely worthless too. The rounds that impact and ricochet are not causing any damage. Here’s my test of the LA-5 with all AP vs the 110. The AI fired 340 rounds of which 42 registered as hits. The result was only a dead gunner.

 

LA5_V_110.thumb.PNG.70baff054f73891d13fc22a1be21aad8.PNG

An AP round impacting aircraft aluminum obliquely with a reasonable velocity should not ricochet. It in fact would cause greater damage than a round striking perpendicular.  This effect is described and illustrated in the Survivablity Design Guide for US Army Aircraft Volume 1. https://apps.dtic.mil/dtic/tr/fulltext/u2/891122.pdf page 106. A .50 cal AP round striking obliquely to aircraft skin tears a large gash across it’s path. It doesn’t deflect off, without causing any damage.  737598253_ScreenShot2021-01-24at6_42_03PM.png.baf5f1434d658e7db3905ba00b0fb392.png

 

 

 

The reason for this is ballistic overmatch. When the diameter of the round is greater than thickness of the material its impacting; The material fails in a shearing fashion due to the ductile nature of the interaction.

1709002529_ScreenShot2021-01-24at7_01_19PM.thumb.png.fc671ee6ae1c116bb9b94fb8106f3cf7.png

 

 

Overmatch Defined on Page 9.

https://apps.dtic.mil/dtic/tr/fulltext/u2/a954868.pdf

Chart From Page 18.

https://apps.dtic.mil/dtic/tr/fulltext/u2/492302.pdf

 

However, even when rounds impact at oblique angles below a critical velocity and ricochet. They cause significant damage to the surface. In aluminum this results in significant petaling and perforation of the material. Even at impact velocities of 300 meters per second. Below is a pic of the effect of 6.5 mm steel ball impacting 1.27mm aluminum plate (double the thickness of aircraft skin.) and ricocheting.

731253579_ScreenShot2021-01-24at9_26_58PM.thumb.png.62207f26e94fd703f1c590b8f440c08f.png


https://apps.dtic.mil/dtic/tr/fulltext/u2/a030268.pdf

 

link to ballistics formulas with primary source references.
https://www.alternatewars.com/BBOW/Ballistics/Term/AP/AP_Pen_Formula.htm

 

They should either disable the ricochet mechanic for AP rounds against aircraft, or model overmatch and an associated damage multiplier due to the spalling and fragmentation that subsequently occurs due to overmatch.

skirmish.2021-01-24_17-33-04_00.zip

Edited by Yak_Panther
added pics and zip of track
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SAS_Storebror
4 hours ago, unreasonable said:

just in order to appease an MP faction that is frustrated by certain aspects of their targets' flight behaviour. 

Whole statement self-disqualified in one singe line.

Congratulations.

 

:drinks:

Mike

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Aurora_Stealth

Think it would be best if people could stick to what common ground there is; rather than jabbing eachother in the arm over what they don't agree on - or what is up for further detailed evaluation. Letting the thread degenerate down the same path we've seen in the past is only going to water down the original (well made) case presented by @QB.Shallot , the QB team and their contributors.

 

What it seems can be agreed on:

 

- Incendiary rounds need to be added at some point fairly soon in future... in order to bring weapon load-outs in line with historical accuracy. This will require resources to be dedicated from the dev. team and will probably come with potential delays to planned content.

- Aerodynamic damage is underwhelming with the M2 .50 calibre and this appears to be out by a significant factor, requiring further evaluation by the dev. team.

- Surface damage is excessive when using HE rounds with weapons of calibre 12.7 to 13mm.

- Ricochet effects (perhaps linked to prev. work on TC) appear to be contributing to inefficiencies with lower calibre weapons.

 

Is there a real need to be more specific than that here? the details of the rest could and arguably (should) be established by the actual developers.

 

No one needs to be disqualifying anyone, because we have common ground - and we have an good excellent development team that can potentially re-assess this when they are allocated the resources to do it. What was made clear in comments by Jason at the end of last year is that the team doesn't have the time and resources allocated to looking at it right now.

 

Cheers, Aurora

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unreasonable
Just now, Yak_Panther said:

It’s not just the .50’s cals that are effected by the ricochet issue though. It’s all AP ammo. 20 mm ap is also largely worthless too. The rounds that impact and ricochet are not causing any damage. Here’s my test of the LA-5 with all AP vs the 110. The AI fired 340 rounds of which 42 registered as hits. The result was only a dead gunner.

 

LA5_V_110.thumb.PNG.70baff054f73891d13fc22a1be21aad8.PNG

An AP round impacting aircraft aluminum obliquely with a reasonable velocity should not ricochet. It in fact would cause greater damage than a round striking perpendicular.  This effect is described and illustrated in the Survivablity Design Guide for US Army Aircraft Volume 1. https://apps.dtic.mil/dtic/tr/fullt ext/u2/891122.pdfpage 106. A .50 cal AP round striking obliquely to aircraft skin tears a large gash across it’s path. It doesn’t deflect off, without causing any damage.  737598253_ScreenShot2021-01-24at6_42_03PM.png.baf5f1434d658e7db3905ba00b0fb392.png

 

 

 

The reason for this is ballistic overmatch. When the diameter of the round is greater than thickness of the material its impacting; The material fails in a shearing fashion due to the ductile nature of the interaction.

1709002529_ScreenShot2021-01-24at7_01_19PM.thumb.png.fc671ee6ae1c116bb9b94fb8106f3cf7.png

 

 

Overmatch Defined on Page 9.

https://apps.dtic.mil/dtic/tr/fulltext/u2/a954868.pdf

Chart From Page 18.

https://apps.dtic.mil/dtic/tr/fulltext/u2/492302.pdf

 

However, even when rounds impact at oblique angles below a critical velocity and ricochet. They cause significant damage to the surface. In aluminum this results in significant petaling and perforation of the material. Even at impact velocities of 300 meters per second. Below is a pic of the effect of 6.5 mm steel ball impacting 1.27mm aluminum plate (double the thickness of aircraft skin.) and ricocheting.

731253579_ScreenShot2021-01-24at9_26_58PM.thumb.png.62207f26e94fd703f1c590b8f440c08f.png


https://apps.dtic.mil/dtic/tr/fulltext/u2/a030268.pdf

 

link to ballistics formulas with primary source references.
https://www.alternatewars.com/BBOW/Ballistics/Term/AP/AP_Pen_Formula.htm

 

They should either disable the ricochet mechanic for AP rounds against aircraft, or model overmatch and an associated damage multiplier due to the spalling and fragmentation that subsequently occurs due to overmatch.

skirmish.2021-01-24_17-33-04_00.zip 1.4 MB · 0 downloads

 

Thank you for posting interesting references.

 

When you say page 106 of 891122 I assume you mean the page in the pdf, not the original page numbering, since that is about toxic smoke hazards. As far as I can see, this section says that shots at 90 degrees make small holes, and the more oblique the angle the bigger the hole. Who knew? Thank God for Big Government. ;) 

 

One could actually test if this is replicated in the game, although probably only with static tests, by presenting a surface to a gun at a variety of angles - not sufficiently oblique to create ricochets -  and measuring the number of hits required to create level 3 damage. 

 

Here is page 106 of the pdf for the majority of the readers of this thread who will not actually look at the evidence, but just cheer or jeer depending on which "side" it purports to support.  Please show me where it says that a Xmm projectile cannot ricochet off a plate less than Xmm thick. The other diagram you show (Effect in variation etc) also does not make the point you are trying to make about ricochets: it says quite clearly "tendency to fail in shear" and "more difficult to fail in shear".  This is a probability, not an absolute limit. Do ricochets happen in the sim more often than they should? Perhaps, but this document does nothing to answer this question. Quite clearly, the tendency to ricochet in the game is a function of the impact angle. (Also possibly the level of damage - more damage = more ricochets, although that is just an observation: not systematically tested). 

 

What bothers me more is that HE rounds do not seem to ricochet, as far as I am aware they always go off on the surface, which I am sure is incorrect.

 

44009482_page106ballistics.thumb.JPG.253cc34c716e407ba8c9ce51daab4af5.JPG

 

 

 

 

 

It is interesting that in 954868 there are AP penetration tables for 90mm AP vs 3 inch armour. 90mm = ~3.5 inches, so "overmatched" according to this definition , which is no more than a useful rule of thumb. The tables only go up to 70 degrees obliquity. Why do you think that is?

 

 

 

 

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@unreasonable

I assume the difficulty of measuring surface area damage on a sheer of that size would be challenging. Also it would be difficult to create a model for them.

 

I think rule of thumb and best case/worst case models shouldn't be discounted. We aren't going to get an overly complex DM due to the number of rounds in the air. The calculations would drastically affect performance.

 

Another variable is the type of material used. This is the difference between 2 different types of Aluminium:

Screenshot_20210125-104003_Drive.thumb.jpg.cefddf39c6b41c65d0c24edd6cd50634.jpgScreenshot_20210125-103944_Drive.thumb.jpg.2d5aadc48f4cc7c58d588c472014f54d.jpg

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unreasonable

@Cass I have no problem with rules of thumb as such, but in the case of a highly complex system where only a few of the inputs and mechanisms can be modelled explicitly, if it is just as easy to insert a probability table as to insert "if x then y", then I would prefer the probability table.

 

Yak_Panther is saying that 13mm projectiles cannot ricochet off aircraft skin. Because "over match".

 

The developers think otherwise, and have a model that incorporates that. So Yak_Panther needs to prove his assertion: the documents he links do nothing of the kind.  Still to read your link though - need more coffee!

 

 

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@unreasonable

Might need a big cup! There's some math's in there that's way over my head but it seems to be an actual working model for assessing upper and lower limits of damage created by AP rounds on aircraft skin. 

 

The example for running from page 58-60 shows a .30 calibre round striking 0.090 inches of aluminium at 60 degrees.

 

Upper limit: 3 inches

Lower limit: 0.658 inches

 

 

Interestingly, lower velocities actually appear to do more damage.

 

Edited by Cass
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=EXPEND=13SchwarzeHand

Assessing the upper and lower limits are worthless values for a game. I see no assessment  of distribution, which is what would really be needed. All in all a nice to have but not helpful for our means afaict

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=EXPEND=13SchwarzeHand

Oh sorry I only looked at the pics you posted. Can you give me the page number pls? @Cass

I scanned through the report and i cannot find anything that relates damge size to probability of occurance, but maybe I´m blind. Of course this would be the relevant probablity and having any section on some probability doesnt help...

Edited by =EXPEND=13SchwarzeHand
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unreasonable
Just now, Cass said:

@unreasonable

Might need a big cup! There's some math's in there that's way over my head but it seems to be an actual working model for assessing upper and lower limits of damage created by AP rounds on aircraft skin. 

 

The example for running from page 58-60 shows a .30 calibre round striking 0.90 inches of aluminium at 60 degrees.

 

Upper limit: 3 inches

Lower limit: 0.658 inches

 

 

 

It says .090 not 0.90   You can find .090 7075-T6 for sale on the www. 

 

0.090 inches is about 2.3mm - ie in the range for aircraft skin. Note that the same page (fig 2-34) shows that at 70 degrees - no penetration. Ie it ricochets. It was probably backed by something for this test though.

 

The higher v = lower damage (up to a point) is counter intuitive at first glance, but it makes sense when you think of a very high velocity bullet as neatly removing the matter in front like a hole punch. When you try to make a hole in A4 by sticking a biro through it, there is always much more of a mess! 

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9 hours ago, unreasonable said:

Under performing relative to what?

Common goddamn sense.

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Don't get too hung up on charts - WRT ricochets there's a wide range of randomness. It starts with the definition of a ricochet, for instance projectile break up, penetration, damage... Thruth is, it is hard to impossible even under test lab conditions to reproduce ricochets exactly. In practice, an aircraft wing is not homogenous (rivits, overlaps, underlaying structures, material properties, existing stresses ...) and results will vary widely.

 

When I went through several sources years ago, I (and others) arrived at the bottom line that ricochets of 0.50 fired at aircraft wings from directly behind are possible. Given the typical volume of fire it's actually likely you'll get some. It would still do some damage.

 

If you're discussing this out of academic interest, by all means proceed. If you do this in order to agree on what exactly should happen at shallow angles of fire, you're wasting your time (with interesting things nonetheless). You can also safely assume that BoX will not model this in detail.

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@unreasonable

Sorry that was a typo, will correct.

 

11 minutes ago, unreasonable said:

Note that the same page (fig 2-34) shows that at 70 degrees - no penetration. Ie it ricochets.

 

I don't think that's the correct figure - can you recheck the reference?

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@=EXPEND=13SchwarzeHand

Thanks. That does make sense. But it's for a 0.9 inch plate, not a 0.090 inch sheet.

 

Edit Apparently appears to be a typo earlier in the report, I've found the one referenced and it is 0.090

 

But @Yak_Panther
source states that the diameter of the round in comparison to the thickness of the material has an effect on whether you see shearing. I.e. if the diameter is bigger it is more likely.

 

 

 

Probabilities are from p.65 onwards it appears but are limited to .30 calibre ammunition on a specific type of aluminium. You would need to make some assumptions.

 

@unreasonable

I have no idea how you extrapolate those probability tables so would need your mathematics skills.

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=EXPEND=13SchwarzeHand

Thx @Cass , afaik these are not numbers that assign the size of damage to a probability. As far as I know, this, is the probability of maximum lateral damage (this is the upper bound) for doing damage in the flight path of the bullet given within degrees (if I read this correctly). You can also see this by looking across the columns, the probability will add to one. So they probably counted the times of maximum damage hits that occured for a certain inclination and divided by all the shots that resulted in maximum damage. It gives you the probability of getting maximum damage for an inclination (e.g you take 12 shots 3 of them do maximum damage on 1 setting of inclination each, then you get a probability of 0,33 for each inclination etc.). If it counted the unconditional probability for each inclination you would have like in the example only an overall probability of 1/12 for each plate ( see how this woulldn´t add to 1), because not all shots cause maximum damage. If the unconitional probability was anywhere in the document it would probably be helpfull.

 

An overall damage (or hole size) size proability is what would be needed for a viable model (or at least one that tries to predict aerodynamic effects approximately)... at least that is not what I found from p65 onwards.

Edited by =EXPEND=13SchwarzeHand
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unreasonable
Just now, Cass said:

@unreasonable

Sorry that was a typo, will correct.

 

 

I don't think that's the correct figure - can you recheck the reference?

 

We may have been referring to different sheets: here we go: text on left clearly states 0.090 inch sheet vs .30 cal bullet, text on right states that ricochets start as you increase from 60-70 degrees.

 

While it is obvious that the ratio of projectile diameter to target thickness is a relevant variable, you cannot credibly assert that "over match" regarding this alone makes ricochets impossible, or even unlikely, irrespective of the impact velocity and angle.  It is also pure conjecture that rounds that ricochet in the game are not in fact doing any damage.  So this whole ricochet business is just a red herring.

 

Interesting report though. I bet the developers already have it: they are Russian and this is a NATO document, after all.....

 

1398229763_ASGAR1.thumb.JPG.43cd2a78ac04875018249f074d70063c.JPG935868695_ASGAR2.thumb.JPG.854da1ace89b4416e03880bfc2e8b217.JPG

Edited by unreasonable
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@unreasonable

Certainly not asserting that. You wouldn't be able to create a model that includes ricochets based off of this report alone.

 

I think we're getting a bit too granular here though. 1C aren't going to create a DM that complex. What this report and others show is that smaller calibre AP rounds certainly have the potential to inflict significant skin damage on sheet aluminium.

 

What we, or they, need to do is use this to create a number of cases and their probability and then build those into the DM. 

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=EXPEND=13SchwarzeHand
3 minutes ago, Cass said:

What we, or they, need to do is use this to create a number of cases and their probability and then build those into the DM. 

 

Im pretty sure that´s what they have done and are doing. If anything this shows that nothing is as clear cut, as we wish it were.

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1 hour ago, =EXPEND=13SchwarzeHand said:

Thx @Cass , afaik these are not numbers that assign the size of damage to a probability. As far as I know, this, is the probability of maximum lateral damage (this is the upper bound) for doing damage in the flight path of the bullet given within degrees (if I read this correctly). You can also see this by looking across the columns, the probability will add to one. So they probably counted the times of maximum damage hits that occured for a certain inclination and divided by all the shots that resulted in maximum damage. It gives you the probability of getting maximum damage for an inclination (e.g you take 12 shots 3 of them do maximum damage on 1 setting of inclination each, then you get a probability of 0,33 for each inclination etc.). If it counted the unconditional probability for each inclination you would have like in the example only an overall probability of 1/12 for each plate ( see how this woulldn´t add to 1), because not all shots cause maximum damage. If the unconitional probability was anywhere in the document it would probably be helpfull.

 

An overall damage (or hole size) size proability is what would be needed for a viable model (or at least one that tries to predict aerodynamic effects approximately)... at least that is not what I found from p65 onwards.

From my understanding, those charts are looking at the probability of maximum damage with respect to the direction of the grain (sheet metal is rolled and as such will have different strength in different directions). As far as @unreasonable
mentioned in a previous post the actual decimals have a different meaning than a pure probability number.

 

Again we're not going to get a granular detail model. If we can understand the probability of a maximum damage hit and then have all other hits be the minimum, that would still be a massive improvement than what we have currently. If .50 rounds are capable of making holes as big as this report says then the aerodynamic damage should be significant during best case scenarios.

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=EXPEND=13SchwarzeHand

that sounds fairly sensible as well. However I am sure they do represent a probability, hence the title and description (and the rather unique trait of all of them across the board adding to 1), however no such probabilites that you could base a model off of. Since you stated earlier that a "model" was pretty much done, and the devs only need to look at the document you provided. So my point is no, this is not a paper that would solve all problems.

5 hours ago, Cass said:

Well well well, it looks like an actual damage model has already created by NATO for us:

 

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@=EXPEND=13SchwarzeHand

Nope you were right I think. As far as I understand it now that is the probability that the maximum damage we be in the direction of the grain/stress not the actual probability of maximum damage.

 

It certainly isn't a 1 stop shop and more sources need to be put together if you want to create a research backed DM.

 

What this report almost certainly puts to bed is the fact that rifle and HMG calibre AP rounds create neat little holes in surfaces when shot into the back of aircraft.

 

So even a minor buff to AP aero damage until further model development can prioritised would be realistic. 

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=EXPEND=13SchwarzeHand
1 minute ago, Cass said:

 

So even a minor buff to AP aero damage until further model development can prioritised would be realistic.


I would welcome that and as far as my intuition goes this is needed.

IMO we should just be careful about picking the right arguments.

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14 hours ago, -[HRAF]Roland_HUNter said:

1944 Germans had shortage of everything?
Boi Ihope you know, the germans has no fuel problem until 1944 april, when 1 yes 1 american suggested to bomb the syntetic refineries.
And the germans produced the MOST in 1944: Most tank, planes everything.
Example: They produced 300-500 BF-109 in 1943/month.
In 1944 they increased it to ~1200/month. Oh and they distributed the big factories into little manufactures. 4-5 big factory into 700 little manufacture.
Bf-109:
1943:6418,
1944:14,152
They produced 1500-2000 Panzer IV in 1943, in 1944-1945 they produced 5500. Panther: 1943: 1200, 1944-45:5000.

 

Germany had to up their production...but even so it was no match for the allies. That's the harsh reality when you engage war on two fronts...

Read some other books...

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Roland_HUNter
5 hours ago, NIK14 said:

 

Germany had to up their production...but even so it was no match for the allies. That's the harsh reality when you engage war on two fronts...

Read some other books...

Who compared? I just proved the previous comment to be wrong, how the germans had nothing or be short of anything in 1944.
Why should I read other books? Other books ll change the numbers? Nope.
And I beg your pardon, how Germany couldn't produce
as many tanks  as USSR what is big as a Pluto, and as many tanks as USA what is bigger than whole Europe(and another continent)

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BCI-Nazgul
21 hours ago, Yak_Panther said:

It’s not just the .50’s cals that are effected by the ricochet issue though. It’s all AP ammo. 20 mm ap is also largely worthless too. The rounds that impact and ricochet are not causing any damage. Here’s my test of the LA-5 with all AP vs the 110. The AI fired 340 rounds of which 42 registered as hits. The result was only a dead gunner.

 

LA5_V_110.thumb.PNG.70baff054f73891d13fc22a1be21aad8.PNG

An AP round impacting aircraft aluminum obliquely with a reasonable velocity should not ricochet. It in fact would cause greater damage than a round striking perpendicular.  This effect is described and illustrated in the Survivablity Design Guide for US Army Aircraft Volume 1. https://apps.dtic.mil/dtic/tr/fulltext/u2/891122.pdf page 106. A .50 cal AP round striking obliquely to aircraft skin tears a large gash across it’s path. It doesn’t deflect off, without causing any damage.  737598253_ScreenShot2021-01-24at6_42_03PM.png.baf5f1434d658e7db3905ba00b0fb392.png

 

 

 

The reason for this is ballistic overmatch. When the diameter of the round is greater than thickness of the material its impacting; The material fails in a shearing fashion due to the ductile nature of the interaction.

1709002529_ScreenShot2021-01-24at7_01_19PM.thumb.png.fc671ee6ae1c116bb9b94fb8106f3cf7.png

 

 

Overmatch Defined on Page 9.

https://apps.dtic.mil/dtic/tr/fulltext/u2/a954868.pdf

Chart From Page 18.

https://apps.dtic.mil/dtic/tr/fulltext/u2/492302.pdf

 

However, even when rounds impact at oblique angles below a critical velocity and ricochet. They cause significant damage to the surface. In aluminum this results in significant petaling and perforation of the material. Even at impact velocities of 300 meters per second. Below is a pic of the effect of 6.5 mm steel ball impacting 1.27mm aluminum plate (double the thickness of aircraft skin.) and ricocheting.

731253579_ScreenShot2021-01-24at9_26_58PM.thumb.png.62207f26e94fd703f1c590b8f440c08f.png


https://apps.dtic.mil/dtic/tr/fulltext/u2/a030268.pdf

 

link to ballistics formulas with primary source references.
https://www.alternatewars.com/BBOW/Ballistics/Term/AP/AP_Pen_Formula.htm

 

They should either disable the ricochet mechanic for AP rounds against aircraft, or model overmatch and an associated damage multiplier due to the spalling and fragmentation that subsequently occurs due to overmatch.

skirmish.2021-01-24_17-33-04_00.zip 1.4 MB · 1 download

WOW!   This is great info and well documented by you.  Thank you!   It appears that at least some of the time the AP will do MORE damage to the skin than an HE round.

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QB.Shallot

While I appreciate the discussion on German production numbers in 1944, or potential API/I shortages, I'd appreciate it more if we kept the discussion on track.

 

This has probably been one of the most productive .50 cal threads to date simply because of all the wonderful resources that the participants have been bringing to the table and breaking down. Please do keep up the good work, I'm learning a lot more than I expected. 

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20 hours ago, unreasonable said:

Under performing relative to what? The physical reality of .50 cal AP ammunition vs aeroplane wings? The game's 13mm HE?  Or gamer desire that a burst of .50 cals should cripple a target in MP?  You cannot agree on the solution to a problem if you have inconsistent definitions of what the problem actually is.

 

The OP points out a difference in the ratios between the number of shots required to reach level 3 damage - ie the most severe level of surface damage possible consistent with the plane still being flyable. I think everyone commenting so far finds the ratio excessive, but they often do not say why.

 

Not just a difference in the ratio. It's that you can pump 85 rounds into a wing and achieve only level 1 aerodynamic damage, and if you pump any more rounds into the wing, it falls off. As I've said twice already, that seems odd, possibly buggy, and should probably be looked at.

 

I can't tell if you're trying to be helpful but communicating poorly, or if you're one of those people who like to troll in threads like this until the mods lock the thread.

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brahguevara

Go punch a hole in a beer can?

 

Actually now I remember I've used a slug gun on beer cans and it does leave a perfect hole if you hit it perfectly.
1128259577_beercans2.thumb.jpg.f83235deec14e36bbddf84061d905d70.jpg
I'm no expert but to me a hail of bullets is going to cause more aerodynamic damage than the hail of metal from an he round.

beer cans1.jpg

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Roland_HUNter
3 hours ago, Alonzo said:

 

Not just a difference in the ratio. It's that you can pump 85 rounds into a wing and achieve only level 1 aerodynamic damage, and if you pump any more rounds into the wing, it falls off. As I've said twice already, that seems odd, possibly buggy, and should probably be looked at.

 

I can't tell if you're trying to be helpful but communicating poorly, or if you're one of those people who like to troll in threads like this until the mods lock the thread.

He is definietly not a troll. Why would he? o.O

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unreasonable
Just now, Alonzo said:

 

Not just a difference in the ratio. It's that you can pump 85 rounds into a wing and achieve only level 1 aerodynamic damage, and if you pump any more rounds into the wing, it falls off. As I've said twice already, that seems odd, possibly buggy, and should probably be looked at.

 

I can't tell if you're trying to be helpful but communicating poorly, or if you're one of those people who like to troll in threads like this until the mods lock the thread.

 

Firstly, thank you for actually answering my question. I am not sure why it is either trolling to ask people for factual accuracy and to be specific about what they think is the problem.  Even if you agree that the ratio looks intuitively wrong, as I do, there is a big difference between levelling up the .50 call AP damage and levelling down the 13mm HE damage.  

 

The OP's measurements are actually for levels 2 and 3 out of the three levels. Please see the screen shots. I also demonstrated that it is possible to achieve level 2 damage (but not level 3) on the 109's mid wing section taking ~20-30 .50 cal hits, although from a different angle, less likely to hit the spars. 

 

Turning to the 109 wing: I do not think the relatively early breakage is a bug as such.  But if it does not reflect real differences in the spars of the real planes, it may be an artefact of the DM's hit-box design.   In the DM the sim's 109 wing has three fairly equal hit boxes, while the 190 and P51 have only two. 


With the way the game calculates "spar hits" (described in some detail by AnP in one of the FC threads) this means that a burst of fire concentrated on one hit box has, I believe, a higher chance of breaking a three hit box wing than a two hit box wing, even if the spar specifications are identical.

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