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Stafroty

AP vs HE ammo comparizon/calculations

I disagree with a lot of what you're saying here but I'm going to focus on this statement. You're saying that HE rounds would do more damage to the skin then AP where the AP rounds will do comparable internal damage.

 

No, you are thinking that i am saying so, a BIG difference. You are saying that i am thinking like that when its really you, who thinks that i am thinking. Ive said many times, that those calculations were against 90 degree sheet(vertical). There is no internal damage with that kind of target, because that target for calculations etc were just for sheet, one layer of duraluminium. How can there be internal structure in that?

 

its about u here, not me.

 

 

.. if it's a machinegun. Putting aside the fact that you're mixing calibers in your comparison you've tacitly admitted that your own methodology is flawed as, just like you said, internal damage may be similar but the skin damage would be dissimilar. This implicitly states that the internal structure of the plane will react differently then the skin will ( which was the point of the Wellington post ) and that the methodology of measuring damage based on the damage done to the skin will be of no help for determining the damage done to the internals.

 

You are all welcome to do that match for those. And then base your claims with them, as compared now, just opinions.  You method is really more flawed compared to mine, actually.

 

And yes with wellington, there can be seen only 1 hit from HE on its fuselage behind the wing(parts of internal structure is missing, (i can calculate you the width between missing parts on internals), on which the fire started on the fabric. It wasnt only HE effect what put that fabric disappear.

There is indeed fire damage included in that picture, and i am not going to calculate that one :) you are again welcome to do it. It could be easy to calculate. just check how big area is fabric behind the area where fire starts, and remove all that kind of skin because of it in rapid speed in game terms to get loss of speed and increase of drag etc Plus that what flames would affect on airflow, as i understand, it affects it, as hot air is bigger in volume than cool, gas expands, and it that happens on wing surface area, it will certainly affect it.

 

 

 

What's more this means you're emphasizing a type of damage that fairly rarely took down planes, part of the reason we have pictures of planes with battle damage of this type is the fact that those who had their structure seriously compromised or critical systems destroyed simply didn't make it back.

 

Im not doing that, you are thinking that i am doing that, its again you who think so. I did area calculations and above claim is your imagination about me. 

 

And yes, we only have like i said, pictures of those which made it. Similar size of area damage to wellies wing would have prevented it from coming back, so there is most likely matter like i earlier said, that wing damage is different than fuselage damage when it comes to flight performance or modeling (game term).

There was 109 in Finland which was hit 2 times in same battle with 37mm M4 cannon from P-39. one in cockpit, wounding pilot badly, and other in tail fuselage, bulging it greatly. It did still made it home but tail bend while it landed and speed dropped low enough so wings didnt anymore support the planes weight, and it started to have more weight on its tail wheel.  He was really really lucky. IF fragments of that shell would have hit control wires etc he would not have made it back in plane or at all. Also it matters where higher cal ammo detonates inside the hull. I think and believe, that in this case it was quite in the middle of fuselage, making damage even in every direction. If it would have been only on other side, it would have ripped only that side open+tearing internals, it would have ripped tail off completelly when by airflow, perhaps. i dont have picture of that 109 tho.

 

IF you look that spit picture i did and added the photo on it, you can see what internals there is damaged in it. ill provide you picture of internal tail fuselage of spitfire, and you can, with your very own eyes look whats inside there, and also see what parts were damaged as well. As i in that picture said, and what can be seen clearly, is that the stuctures of that spit were weakened, and that most likely after spit was hit, spit pilot pulled really hard to get away from front of that 109E with 20mm MG-FF cannons, and that tight turn made most likely the skin damage on top of tail fuselage.  Thats my conclusion about what happened.   Perhaps that happened normally too wihtout damage from hits, just pull hard and tail bend? is that better?

 

 

Starting the analysis from the energy going into the shell when it's fired will always yield more consistent and better results.

 

based on what else than just table data?  they are purely calculations(by williams) without ANY  point of reference to actual damage they did. It is the simpliest way there can be to calculate damage. It cannot be more simplier.

It doesnt take even caliber in account (thickness of  a shell) 

based on that way of calculation with K/C Energy, i could fire 1mm cal AP rounds which are 2 m long, at 1000m /sec and make HUGE damage, based on KE alone.  it doesnt take in account overpenetration(complete penetration of target=KE loss from that) or anything else. It is just weight &speed = KE result  or weight & speed & chemical = HE result, nothing more.  There is no other factors in that, nothing. And u decide that it is more accurate :)

Well, perhaps it is with AP rounds against ARMOR plate. But again, its flawed because HE ammo arent too able to penetrate armor. But according that table they are, 20mm HE even better than .50cals ;) So HE is more penetrativethan AP because it has more energy?  .50 cal round with HE in it but same weight than AP ammo from .50cal, at close range round with HE in it has more energy on it, same weight/speed but plus chemical energy.. ur logic is totally flawed if you base it in that. Its just that you are so used to believe that it is so that those numbers carry the absolute truth, and theres nothing that can change that.

so in that sense again its flawed.  So with above mentioned you base ur logic on less evidental, more simplier calculation than what i am doing, actually.

 

As an example for the problematic nature of what your analysis is suggesting

 

its not suggesting, you are. They just tell areal damage difference at 90 degree angle. nothing more. you are suggesting and reactin about ur own suggestion againt me.

If target sheet(3mm thick)  is hit with at 90 degree angle ammo(vertical) round will penetrate 3mm of it, there is no more it left to penetrate.

But if that sheet is hit at 40 degree angle, round has to penetrate about 5,2mm of that same sheet. but if it is hit at 5 degree angle, penetration distance thru it is 38mm. its 1266,66% more penetration distance in that sheet ( longer cut in it = way bigger area destoyed) ponimaje?.

That is if the round keeps its trajectory whole penetration distance without yaw.

 

take for example the ammo loadout of the early spitfire, which certainly seemed to shoot down planes historically, and compare that potential firepower you're estimating it to be, less then a high-end estimate from an HE round. Knowing that even 20mm rounds usually required more then a single hit to down an aircraft it seems impossible for a spitfire or an 8 gun hurricane to ever shoot anything down when it requires their entire 2560 round loadout to hit the target to get the effect of a single 20mm round. Given the accuracy rates of pilots in WWII and the nature of an 8 gun wing-mounted torrent of bullets I doubt it's even plausible for the lowest suggested power difference between 20mm and 7.62, 392:1.

 

again, you suggest and estimate that againt 90 degree hits with every round. its you, not me who does that. you are suggesting, its you against who  you have to fight with this one ;) im not saying that it is so like you said with spitfire, im not claiming that it is so, im not saying that spits werent able to shoot down planes because my FIRST calculations againt 90degree angle doesnt prove that because its just a single layer of aluminium with no stucrures behind it.

 

It is you who are fighting here against your own conclusions/suggestions, and not much i can do about it.  Dont blame me if you manage to come up with suggestions (which you project as my suggestions) that you cannot accept.

 

hey, even i cannot accept those what you say :) 

 

Just stop saying that i suggest. im not.

 

 

 

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Everything you said there is great and makes sense as a method for developing the DAMAGE MODEL but is and will remain flawed as a way of calculating the damage potential of a particular round.

It'd be like trying to calculate the amount of radioactivity released in Chernobyl by the rate of cancer in the affected population instead of looking at the amount of radioactive material present. Looking at this backwards tells you more about the susceptibility of people to radiation then it does about specific quantities released, likewise with damage models and the power of rounds.
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It's quite simple: you are trying to compare HE versus AP damage in terms of being able to kill aircraft, and your results haven't produced anything even remotely resembling reality.

 

You own method of calculations say a 20mm HE shell would inflict similar levels of damage to an aircraft as a 203mm AP shell, which is frankly completely absurd.

 

This has happened because your method for comparing AP vs HE is inherently FLAWED.

 

 
i think the problem in here is you, not my calculations. It seems you fail to read correctly, maybe its because im not native english, or too good writing it.
 
But ive made it clear that my target is sheet of aluminium. NOT AIRPLANE.  see,  You see airplane there, when i say SHEET of ALUMINIUM.   its a BIG DIFFERENCE and thus your logic is making NO SENSE AT ALL.
  Its you who makes up those suggestions and all, and project them to me. You fight against ur own flaws here. 
 
  READ what is written, dont fall in your minds delusions. Talk about what we are talking here or go away if you cannot make difference between sheet of aluminium and airplane. They are really 2 different things.  IF you fail to see difference, it is not in my hands to change that.  
 
Jaakariliike answered already pretty well to you, but ill  also say something.
 
and stop suggesting that i am suggesting. its you who does that, not me.
 
 

 

Compare the energy levels of a 20mm Mine shell to a 203mm AP shell.

 

20mm Mine shell: 92 gram weight, 20.24 grams of HE (PETN), 750 m/s muzzle velocity

Kinetic Energy = 25.88 kj 

Chemical Energy = 117.59 kj (and I'm overestimating that by assuming all of it is PETN, which it wasn't; only about 90% was).

Total energy = 143.47 kj

 

203mm AP shell fired by a 8"/55 naval artillery: 152 kg, 760 m/s muzzle velocity

Kinetic Energy = 43,897.60 kj

Chemical Energy = not gonna bother finding out the HE filler charge size, or work out its energy.

 

 

i bet you calculated it all right, i dont deny it, at all, or even check it. i trust you on this one, blindly.

 

 

Now, compare the 203mm AP shell has 306 times as much energy as the 20mm Mine shell(this far im with you); even if the 203mm AP shell only transfers a grand total of 1% of its kinetic energy into the aircraft it impacts, it is still delivering more energy than the 20mm HE shell.(i dropped, you talk about airplane here, but i have to ask you, how big hole against aluminium sheet would that 203mm AP round do at  close range with its highest speed? can you calculate that for me? and explain as well with evidental images too? one question, really simple one, i bet you can answer that one as you were able to calculate such a nice formulas there, i bet you are even better than i am at math :))

 

Frankly, even 10% is a very low amount of energy to transfer, and with over 4 megajoules of energy delivered, the 203mm is going to tear the target aircraft to shreds even if it passes through one side and goes out the other.

 

and again this againt aluminium sheet, would both make hole on it, and what size?

 

 

 

Sure, lets do a 3-dimensional volume comparison.

 

(i like this one)

 

20mm HE shell with a 20cm diameter sphere = 4,188.79 cm^3

200mm AP shell, passing 1 meter through target (20cm diameter x 100cm length circular cylinder) = 31,415.90 cm^3

200mm AP shell, passing 0.5 meters (20cm diameter x 50 cm length circular cylinder) = 15,708.00 cm^3

200mm AP shell, passing 0.2 meters (20cm diameter x 20 cm length circular cylinder) = 6,283.19 cm^3

200mm AP shell, passing 0.134 meters (20cm diameter x 14 cm length circular cylinder) = 4,209.73 cm^3

 

So provided the 200mm AP shell passes at least 130mm through the target, the volume it effectively destroys is greater than the 20mm HE shell.

 

your formula is totally flawed IF you talk about airplane here in 3D as airplanes are not solid objects, but quite hollow.  Even engines arent solid.

But that is how AP round would most likely do, if it hits solid object. But plane, in this calculation is not, so areal damage gets MUCH smaller than the numbers show ;)

So, you werent at all ANY better with this, see, it isnt that easy, is it?

But please, keep calculating, and you get idea of what im discussing here, it helps you to get grip and is also really helpful to me as well, as it makes me taking more and more things attension.

 

And most aircraft had wings considerably thicker than that; take the P-47, it had 307mm thick wings at the root.

 

but not solid ones.

You can calculate stuctural and skin volume of wing section, lets say 50cm patch of wing. from rear to leading edge. calculate how much there is THIN air in it. Then calculate again your above calculation, and take in account the amount of thin air in it, and where the round hits it, and in which angle, does it cut other side skin whole path, etc. provide picture too which shows the diameter of shell on its trajectory thru the planes 3D picture.

Here is wing of E model of 109. You can use that one, just take the area damage from that mg-ff cannon to wing tip area. just first calculate how long distance there is from cannon to wingtip so you get measured good. Sure you can use other 3D  blueprints as well which show  what parts is being hit. 

 

ww2_messerschmitt-bf-109-a.jpg

 

As long you arent providing this information your claim is totally worthless as its most faraway from reality and truth.

 

Here is real life wing from 109 Buchon(hispanos mounted in wings, different engine etc) it has quite similar structure as 109 did in ww2. that shows pretty well the insides of wing, you can use that as well, just put measures on it too. ill provide you another picture too for your project that you were willing to do as volunteer (yes im projecting here like u did to me and take it as truth and blame you for it =) )

 

109g6 wing span is 9,92m, but you cannot just divide it with 2 because there was fuselage too, it would give you too long wings. so you need to find bluepring from which you can do your math to find wing length. as well, for the picture, notice that the wingtip is also missing, so you have to take that too in account.  also wing is bit angled, so you really need to calculate the distances between ribs etc inside of that wing too to fit in the photo. that wing lacks the skin on upper surface and some controlling parts etc. but you are free to find better one.

 

So againt your 3D formula, this picture show that you need to re-calculate it heavily, to fit with real target, not just solid object ;)  it gets hard. thats why i stick with 2 D  i can calculate with 2 D the areas eaten, just taking in account the angle it hits the different surfaces.  I bet you end on that too ;)  but you can prove me wrong too.  

 

(you just need to find measures for the pic, then draw projectile thickess lines over the wing, then draw circes (oval shape if not directly from camera direction hits.)  then you can calculate the area what has been damaged, in 3D or 2D, up to you. include in that also 20mm AP and .50cal AP rounds as well pls  and do that in various angles.   put also few surface detonations in different places from 20mm with half the sphere outside the skin and few inside detonations with delay fuse in other few other places, with sphere also in those, which also show which part of the shere is in contact with structure/skin, to get numbers for those areas too  and to illustrate it to us.   You could also do that same with P47 wing, and against other planes as well, pick your choise.  its nice that you actually agreed to do this all for us :) we are really thankfull for that ;)  if you need pictures/photos lemme try to help you to prove me wrong. (way i am calculating this atm is just by looking the picture,and trying to figure how many layers rounds would penetrate in average etc. but as you might now understand, it isnt that easy ;)  its easy to critize but not easy to do with time it takes :)  So im really glad and others i believe too are, that you speed up this process.

 

Buchon%202012-04-20%2813%29%20Kopie.jpg

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Everything you said there is great and makes sense as a method for developing the DAMAGE MODEL but is and will remain flawed as a way of calculating the damage potential of a particular round.

It'd be like trying to calculate the amount of radioactivity released in Chernobyl by the rate of cancer in the affected population instead of looking at the amount of radioactive material present. Looking at this backwards tells you more about the susceptibility of people to radiation then it does about specific quantities released, likewise with damage models and the power of rounds.

im pleased that you figured that out, and also more that you are willing to help with the issue. As you can now perhaps understand, its more than just KE and CHEMICAL ENERGY COMBINED to be more accurate with damage done ;) 

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im pleased that you figured that out, and also more that you are willing to help with the issue. As you can now perhaps understand, its more than just KE and CHEMICAL ENERGY COMBINED to be more accurate with damage done ;) 

 

Sure, which is the first plane who's damage model you'd like to analyze to work out a sensible damage model.

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I thought he pretty clearly stated that he was just trying to show that HE round hits should have a much more significant impact on the flight characteristics/handling of the damaged fighter than AP hits.

 

I missed that; the OP is rather hard to understand.

 

For surface skin damage, HE would definitely be superior to non-explosive projectiles. Internal component damage? Not so great, but probably still better than a completely inert projectile of the same caliber.

 

 

 

Why do you think "even 10% is very low"? It entirely depends on what you're hitting and with what. If you fire a .50 BMG at 1mm thick sheet metal, you're going to trasnfer maybe 1% or less of its energy.

 

That depends on the properties of the 1mm thick sheet metal; if it is harder and denser steel armor plate, then the projectile will transfer more energy than if it were a sheet of soft and low density aluminium aircraft skinning.

Internal aircraft components would generally be harder and denser than the skinning, although little would be as hard/dense as the occasional bits of armor plating.

 

The volume of the component that the projectile penetrates through would also be relevant to how much energy is imparted. I suspect that a projectile passing through the gasoline in a fuel tank is likely to transfer more energy than it would by passing through the aircraft skin.

 

 

And it depends on the projectile a lot too; an armor-piercing projectile would use a lot less energy to penetrate than a ball or HE shell.

Given .50 BMG Ball ammunition has less than 1/2 inch steel armor penetration (maybe around 8-10mm penetration?), I guesstimate it could use around 10% of its KE to penetrate a 1mm thick plate of armor.

 

To penetrate a 1mm thick of aluminium aircraft skinning though? I'd guess maybe 1/10th of that at best, for 1% of its KE.

But then going through a some structural ribs and a fuel tank? That would absorb considerably more energy but I don't even know where to begin to estimate it.

 

 

A 203mm diameter projectile now, that would require more energy to penetrate the same distance as a smaller caliber projectile (although it isn't a linear equation), so it transfers considerably more energy for the same distance of penetration.

 

I don't have a clue how to calculate the energy transferred by such a projectile though, but I suspect it would be a lot of energy, even for a glancing impact.

 

 

KE transfer appears to be rather complicated to calculate though, and I just don't have the physics education to know how to do it.

 

 

 

Wow, what fighter has 130 mm thick material in it?? The only thing I could think of is the engine block or a shot the whole way from nose to tail (or vice versa).

 

Most aircraft have a significant amount of structural ribbing, which is considerably thicker and tougher than the skinning.

 

And apart from the outer-wings and rear fuselage/tail region, most aircraft in WW2 tended to be jammed full of various components, like engine, fuel/oil tanks, radios, oxygen bottles, turbochargers, radiators, guns, ammunition, fuel lines, control lines, landing gear, the cockpit and numerous other things.

 

 

 

Oh, the P-47 had 307mm thick solid metal wings, did it? 

 

I never said that; you appear to be putting words in my mouth.  :Ps

 

 

 

based on what else than just table data?  they are purely calculations(by williams) without ANY  point of reference to actual damage they did. It is the simpliest way there can be to calculate damage. It cannot be more simplier.

 

Actually, there are some points of reference, like the US Navy's '3x 0.50 cal for 1x 20mm' and and German Luftwaffe assessing the 30mm MK 108 as having 4 times the firepower of the 20mm MG 151/20.

 

There is also the various 'percentage probability of kill' figures for the US study against P-47s and B-25s.

Edited by Cuteling
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I missed that; the OP is rather hard to understand.   well, ive brought that target type pretty well up, and often.

 

For surface skin damage, HE would definitely be superior to non-explosive projectiles. Internal component damage? Not so great, but probably still better than a completely inert projectile of the same caliber.

 

this again is up to how close it goes off internal parts. if there is stucture right on spot it lands, that is also quite heavily destroyed completelly on its destructive blast radius, and over that distance, material is bent, more or less, or detached completelly or totally from rivets. it is different type of damage than what AP rounds do. and also whole point of this thread as well.

 

 

 

 

That depends on the properties of the 1mm thick sheet metal; if it is harder and denser steel armor plate, then the projectile will transfer more energy than if it were a sheet of soft and low density aluminium aircraft skinning.

Internal aircraft components would generally be harder and denser than the skinning, although little would be as hard/dense as the occasional bits of armor plating.

 

what would be end result of that penetration on target?

 

hole of what size compared to caliber?

 

how much the size changes between amount of energy used to do it? :)

 

The volume of the component that the projectile penetrates through would also be relevant to how much energy is imparted. I suspect that a projectile passing through the gasoline in a fuel tank is likely to transfer more energy than it would by passing through the aircraft skin.

 

well, doesnt it still make hole of its diameter if its vertical hit (90degree) longer cut if angled one. Sure, if gas tank would be hit, it transfers alot of its KE to it, quite surely, all, depending the ammo. And when that happens, it turns hydralic energy, which would then expand in direction where there is least resistance., and if there is no empty space at all it would likely rip weakest spot around the fuel tank. But this applies with full tank. (just check how concorde accident happened, big piece of landing gear hit the bottom on fuel tank area, causing it to do above effect)

 

 

And it depends on the projectile a lot too; an armor-piercing projectile would use a lot less energy to penetrate than a ball or HE shell.

Given .50 BMG Ball ammunition has less than 1/2 inch steel armor penetration (maybe around 8-10mm penetration?), I guesstimate it could use around 10% of its KE to penetrate a 1mm thick plate of armor.

 

There is somewhere some test around this. Sure ball ammo is soft compared to steel core. both i believe will easily penetrate aluminium, but steel its different, as lead starts to spread all over and uses just blunt force to go thru, at larger area than AP with tight area, as it dosnt deform/spread.

 

To penetrate a 1mm thick of aluminium aircraft skinning though? I'd guess maybe 1/10th of that at best, for 1% of its KE.

But then going through a some structural ribs and a fuel tank? That would absorb considerably more energy but I don't even know where to begin to estimate it.

 

yesterday i checked one site which tested ball ammo against car doors, and had "target" behind doors. which was suprising that single car door prevent most of the 5,56 rounds (FMJ) and it went to pieces while penetrating. This might also explain why there wasnt 7,62 exit holes on that white door video. they simply broke up in pieces too small to come thru. AP rounds are different story, they lose only jacket, might "keyhole" most likely too. i think keyhole is the term to explain if projectile yaw?

 

 

A 203mm diameter projectile now, that would require more energy to penetrate the same distance as a smaller caliber projectile (although it isn't a linear equation), so it transfers considerably more energy for the same distance of penetration.

 

it doesnt matter how much energy it transfers because it does leave hole of its size if it doesnt "keyhole" :)  Energy is used to create that hole and is just measured from material it does penetrate as well its angle etc. result is hole  :)

 

 

 

I don't have a clue how to calculate the energy transferred by such a projectile though, but I suspect it would be a lot of energy, even for a glancing impact.

 

use the picture i provided earlier. well ive upgraded it bit, ill post it so you get idea of how long distance round has to travel inside the plate in different angles. just put numbers in % or something if you want to simulate different thicknesses. that picture is against aluminim sheet of 2 thicknesses.  3mm and 0,5mm and doesnt have any glancing(=ricochet) effect. So i just put them to go cleanly through. sure at least against steel, but thicker, angle etc sure will create ricochet effect, and some of the projectile energy is wasted because of that. (it turns projectile bit sideways while entering, but turns out in other way when it comes thru)(notice that effect in chinese sabot picture)

this is old picture and most likely i will put something on it more, to make it more informative. It matters alot also, which kind of nose/cap AP rounds have, on penetration value. (LOS = line of sight)

 

10mmangle_of_attack1.jpg

 

 

 

Most aircraft have a significant amount of structural ribbing, which is considerably thicker and tougher than the skinning.

 

agree, its pressed in form to make it stronger, and i believe material thickness is more than on on skin (im not sure about this though)

Though, not so much of those "struts" there. i think pic is taken from behind towards cockpit. hatch on the low right tells it.

those oval shaped rings arent that thick as it seems, they are just formed so, to make them more stiff. round holes in them have their edges bend at camera direction, and those tell something about their thicknes.

They are round because other shapes reduce its strength (dunno bout oval ones) Also the edge of them is bent so it keeps its strength even with such holes in it. so what happens when u hit AP round on one of those? it makes hole, which also is bent, unless it hits edge of it, which is far more effective btw.

heres pic of spit  tail fuselage:

 

2504091266_6311993b7d.jpg

 

 

And apart from the outer-wings and rear fuselage/tail region, most aircraft in WW2 tended to be jammed full of various components, like engine, fuel/oil tanks, radios, oxygen bottles, turbochargers, radiators, guns, ammunition, fuel lines, control lines, landing gear, the cockpit and numerous other things.

 

 

Tail section was quite empty on fighter planes as were wings as well. only nose part was quite full of stuff and P-39 behind pilot.

They werent so full of gear. 109 and fw190 had fuel tanks under and behind pilot.  just check blueprints. this was to keep mass in center the plane, which helped it turn faster.

heres again spit with war gear on :)

some radio at closest to camera. It has that hatch on its side for maintenance purposes on picture i draw ealier (and was mostly destoyed by those 3 hits ;)

oxybottles on the floor most likely.

 

spitfire_fuselage.jpg

 

 

 

 

I never said that; you appear to be putting words in my mouth.  :Ps

you did say it with your calculation formula :)

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just one question came to mind. 

 

If AP ammo was and is so good against aircrafts, why dont they just use it againt airplanes still?

 

 

there is nice and good cannons of big caliber, just use AP ammo on them and take HEI-T ammo off.  ;)

 

vulcan 20mm  6000rpm(first second isnt at full rate, takes time to accelerate at full rpm, thats why you hear its sound change from the beginning of burst when rpm is going up.

 

M56A3/A4 HEI 102 9 g HE (RDX/wax/Al) and 1.5 g incendiary 1030 Nose fuzed round, no tracer. 2 m effective radius to produce casualties to exposed personnel. Fragmentation hazard out to 20 m. 12.5 mm RHA penetration at 0 degree obliquity at 100 m range.

copied that so ppl can compare those holes on that red car which was hit by this cannon, but with training rounds. Those above ammo are for real deal and i bet they got bigger punch than training ones ;)

and thats still 9g of RDX. ( = 14,4g of TNT R.E.)  (= 1,6x more powerful than TNT, PETN is 1,66 times)

(used also SAPHEI ammo and API)

 

 

mauser BK27 27mm  1700rpm right from first shot.  Aircraft use HE and HE-SD ammunition, naval uses Frangible Armor Piercing Discarding Sabot (FAPDS).

(these M********* still go with HE only, perhaps they are about to lose another war if they keep going :D  )

Edited by Stafroty
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  some 450g/1lbs of black powder against car :) notice  the exlosion color adn type in normal speed. reminds bit of .50cal FW dewinging vids ;)

 

 black powder amount equals to 250g ot TNT, 110g more than mk108 MG round. (77% more)

 

that can be more effective than real explosives during ww2 which still is used in det cords etc ?  (problem with PETN is that it is quite sensitive, TNT RDX etc arent as sensitive, but also, not as fast burning too.

 

 black powder amount equals to 250g ot TNT, 110g more than mk108 MG round.

 

http://www.youtube.com/watch?v=gDTC3kCG2v8

 

here is ambulance with 3 lbs of C4, 13 times more TNT R.E. than 30mm MG, but also, the space inside the car as well material its build is different, but effect is big :)

 

http://www.youtube.com/watch?v=vua6IAHeoc4

 

 

 

here is CV9040, with 40mmL70 bofors gun using 3P ammo with some 120g of PBX in it. (plastic bond exlplosive, octogen)

= 204g of TNT  = 45% more than in MK108 30mm MG round. again target is Many times more bigger in space than aircraft fuselage/wing would be. also material they are build is stronger.

http://www.dtic.mil/ndia/2003gun/boren.pdf

 

http://www.youtube.com/watch?v=-3hC0vsZ5-8&feature=player_detailpage#t=79

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 it doesnt matter how much energy it transfers because it does leave hole of its size if it doesnt "keyhole" :)  Energy is used to create that hole and is just measured from material it does penetrate as well its angle etc. result is hole  :)

 

The energy the projectile uses to travel/penetrate through the aircraft doesn't just vanish though; much of it gets transferred to the rest of the aircraft, which has various effects like vibration/shock that can literally tear the aircraft apart if the energy is high enough (as with a high caliber hit).

 

 

 

Tail section was quite empty on fighter planes as were wings as well. only nose part was quite full of stuff and P-39 behind pilot.

They werent so full of gear. 109 and fw190 had fuel tanks under and behind pilot.  just check blueprints. this was to keep mass in center the plane, which helped it turn faster.

heres again spit with war gear on :)

some radio at closest to camera. It has that hatch on its side for maintenance purposes on picture i draw ealier (and was mostly destoyed by those 3 hits ;)

oxybottles on the floor most likely.

 

Yeah, there isn't much in the rear section that is vulnerable.

Most aircraft would have been more difficult to destroy with shots from behind as a result.

 

 

 

just one question came to mind. 

 

If AP ammo was and is so good against aircrafts, why dont they just use it againt airplanes still?

 

Because for projectiles of the same caliber, HE generally was superior.

AP just wasn't inferior to the point of being hundreds of times worse at killing aircraft as I previously thought your calculations were implying.

 

 

Note AP still is used to some degree with anti-aircraft autocannons; I think some anti-aircraft guns used mixed AP/HE belts, and the Phalanx CIWS on US Navy warships uses tungsten cored AP to penetrate anti-ship missile warheads.

 

Here's an image of a 23mm ZU-23-2's ammo belt; based on the shell tip colours, there appears to be two ammo types in that belt, in what looks to be a 1:3 ratio.

I'm guessing that could be an AP/HE mix.

zu23_afp_0222_01.jpg

Edited by Cuteling
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The energy the projectile uses to travel/penetrate through the aircraft doesn't just vanish though; much of it gets transferred to the rest of the aircraft, which has various effects like vibration/shock that can literally tear the aircraft apart if the energy is high enough (as with a high caliber hit).

 

not exactly true. It would shock, if material would have some resistance against projectile penetration. Duraluminium doesnt much have it.  You logic would also mean, that shooting those guns sending those projectiles would also get damaged because of shock waves due gun recoil transferred from guns to the rest of the aircraft.... So should use of .50 cals rip P47 off? :)

 

i got video proof for you to see and learn, notice that target "wing" isnt attached to anything, and its first shot with 20mm cannon, then .50cal and some light cal rounds as well. it doesnt much fly off, even if it is really light piece of normal aluminium. It isnt resisting the penetration almost at all, compared to steel plates which gets KE transferred to them while projectile penetrates. according your logic, the aluminium target should fly FAR away from 20mm and .50cal hits.

 

see here:

 
 

 

Yeah, there isn't much in the rear section that is vulnerable.

Most aircraft would have been more difficult to destroy with shots from behind as a result.

 

so you changed your opinion about rear filled with stuff?

and now it takes alot to destroy it?

 

Wow, you were proven wrong and things go upside down ;)

 

Explain in your terms why it is as you claim? Less equipment to suck up all that KE, like radios. (which has nothing to do with plane structure)

Im not really following you here now. Clarify pls.

 

it seems like you WANT somekind of RIGHT kind of answer to support your need. (just assuming this, but this is impression i got from you, and it seems to be biased, correct me if im wrong. Why i also have a hunch that there might be bias? its cos u were really quiet when you saw those pictures for very little damage i put there for cannon ammo. you didnt say a word  ;)s  )

 

If tail would been filled with all kind of stuff, it would have impacted at least these things:

 

AP rounds would be more ineffective for penetrating from rear to front, or sideways. makin it really hard for those to dig on deeper. It would have reduced AP ammo effectiveness against plane internal structure.

HE ammo would have had boost for their pressure most likely, as more stuff there is inside the fuselage, less open space there is, and that leads higher pressures with explosives, as big space isnt dampening it down. Sure its fragments would have suffered  in effectiveness againt planes structures.

 


Note AP still is used to some degree with anti-aircraft autocannons; I think some anti-aircraft guns used mixed AP/HE belts, and the Phalanx CIWS on US Navy warships uses tungsten cored AP to penetrate anti-ship missile warheads.

 

= Frangible Armor Piercing Discarding Sabot (FAPDS) = the core splinters after impact making good damage to internal parts, which is different thing that what normal AP round is, which just is one piece going thru.

 

Here's an image of a 23mm ZU-23-2's ammo belt; based on the shell tip colours, there appears to be two ammo types in that belt, in what looks to be a 1:3 ratio.

I'm guessing that could be an AP/HE mix.

 

i dont, you gotta check that nations ammo data and color codes to be sure ;)

AA guns are sometimes also used againt ground targets too (on which they are pretty good ;)

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 not exactly true. It would shock, if material would have some resistance against projectile penetration. Duraluminium doesnt much have it.  You logic would also mean, that shooting those guns sending those projectiles would also get damaged because of shock waves due gun recoil transferred from guns to the rest of the aircraft.... So should use of .50 cals rip P47 off? :)

 

Recoil doesn't work like that; it is a more gradual force of momentum than a rapid impact shock.

 

Aside from that, I was talking about large caliber projectiles like a 203mm shell, which wouldn't be fired from a plane to begin with, as the recoil would damage or destroy the firing aircraft.

 

 

 

according your logic, the aluminium target should fly FAR away from 20mm and .50cal hits.

 

You are using Strawman arguments.

 

 

 

so you changed your opinion about rear filled with stuff?

and now it takes alot to destroy it?

 

Wow, you were proven wrong and things go upside down ;)

 

it seems like you WANT somekind of RIGHT kind of answer to support your need. (just assuming this, but this is impression i got from you, and it seems to be biased, correct me if im wrong. Why i also have a hunch that there might be bias? its cos u were really quiet when you saw those pictures for very little damage i put there for cannon ammo. you didnt say a word   ;)s  )

 

This is an Ad Hominem.

 

If you don't believe your calculations represent relative effectiveness of HE versus AP at killing aircraft then we don't have anything more to discuss and I'll be on my way out.

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Recoil doesn't work like that; it is a more gradual force of momentum than a rapid impact shock.

 

Aside from that, I was talking about large caliber projectiles like a 203mm shell, which wouldn't be fired from a plane to begin with, as the recoil would damage or destroy the firing aircraft.

 

so why to take it even in discussion? :)

 

 

 

 

You are using Strawman arguments.

This was if you were speakin about hitting plane with 20mm, .50cal etc . I didnt think that you might mean 203mm hit. You know, it was really hard to guess that you were speakin that caliber ;) also, even with it, it would cut in like in butter at high speeds. But if the shell would fly like 50m seconds or slower, sheets on plane would perhaps wrap around more likely than it to penetrate them. (if rivets would rip)

 

 

If you don't believe your calculations represent relative effectiveness of HE versus AP at killing aircraft then we don't have anything more to discuss and I'll be on my way out.

 

i think it is better this way, ill open door for you.

 

  Im talkin here about damage difference between 2 types of ammunition against various target sheets, as well im using real life photos to back them up, as well more modern ones, like videos.

 

Check the name of this thread

 

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i think it is better this way, ill open door for you.

 

  Im talkin here about damage difference between 2 types of ammunition against various target sheets, as well im using real life photos to back them up, as well more modern ones, like videos.

 

Check the name of this thread

 

Thank you, enjoy your thread.

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heres picture from .50 cal hitting thick aluminium block.  It clearly shows  the hole size with direct hits. 50calvs_aluminiumblock.jpg

Just bumbing up. 

Gonna get better comparison between different ammo from 20mm-40mm cannons with different ammo (HE, HE-M, AP) as well between AP ammo from machineguns 7,62mm- 12,7mm.

takes some time to get it all up.

Edited by Stafroty
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found picture of that NEOPUP 20mm HEI ammo, cut through pic. 

 

"Standard ammunition at this time is available in HE, HE-I and TP (practice) variety, with other types being in development. Weight of the round warhead is listed as 105 gram, and it seems that new round consists of a standard 20mm projectile (as used in aircraft cannons) loaded into short, straight-walled case of 42mm length. All ammunition is point-detonating only"

 

 

 

paw20-3-756036.jpg

 

 

http://machinesforwar.blogspot.fi/2010/05/denel-paw-20-neopup-handheld-grenade.html

 

does point detonation only mean=impact fuse?  at least i analyzed it that way earlier.

Also, i think i didnt guess too far with HE amount. cant remember, as its clear this round is based on fragmentation effect againt infantry. thus thick walls on it. Someone could make rough calculation about the amount of space for that explosives in that round. its about 1,3 centimeter thick round stick inside of it, and about 3cm long. how much space that it? :) anyone?

If its RDX in it, cool, it also might be octagen.  yes, modern ammo uses still the same explosives than what was used back in history, unless you want to use one of the most effective one, which cost more than gold per weight, which has never been produced enought for even testing purposes.

 

Anyway, comparing that cut  picture to other HE ammo from 20mm gives quite accurate idea of 20mm cannon damage potential with HE frag ammo, and that times 2-3 gives idea of 20mm minengeschoss ammo potential in area/overpressure against structures/skin.

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