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Jetbuff
01-28-2006, 05:28 AM
I'm wondering if you have a lot of experience about bomb blast radii and effects?

The reason I ask, is that I find most bombs in IL-2 to be, well, puny. Indeed, the only bombs that meet my expectation are the 5000kg Russian monster on the Pe-8, the Mistel and the V-1. I believe that tanks require a direct hit because of the absence of any terrain deformation but even so I cannot reconcile a narrow miss by a 1000lb/500kg bomb to the often pitiful damage it inflicts.

However, my expectations can easily be wrong, so I'm hoping you, or anyone else with first hand knowledge on the topic can weigh in. Cheers...

Jetbuff
01-28-2006, 05:28 AM
I'm wondering if you have a lot of experience about bomb blast radii and effects?

The reason I ask, is that I find most bombs in IL-2 to be, well, puny. Indeed, the only bombs that meet my expectation are the 5000kg Russian monster on the Pe-8, the Mistel and the V-1. I believe that tanks require a direct hit because of the absence of any terrain deformation but even so I cannot reconcile a narrow miss by a 1000lb/500kg bomb to the often pitiful damage it inflicts.

However, my expectations can easily be wrong, so I'm hoping you, or anyone else with first hand knowledge on the topic can weigh in. Cheers...

WWSensei
01-28-2006, 06:14 AM
Well, I've actually dropped MK-82 (500lbs), MK-83 (1000 lb), and MK-84 (2000lbs) bombs on soft and hard targets in real life. MK-82 danger close on soft targets was about 300 meters. These weren't JDAM equipped and pretty much just like their WW2 counterparts in the dumb bomb category.

I've put a MK-82 about 30 meters from a T-72 (static unmanned target) and flipped it 20-30 meters. A MK-83 at around 50 meters distance of impact tore a turret off another and a MK-84 made one into 2 or 3 fairly large chunks of metal.

I would think a T-72 would represent a pretty tough tank on a WW2 scale.

Bomb blasts in this game are not only modelled weak, they are modelled in strange ways and they are modelled differently online from offline.

I've had in-game bombs dropped on a runway and completely unharm to aircraft sitting no more than 30 meters away yet toast another aircraft 300 meters away. Offline I've dropped an SC-500 in the middle of a diamond formation of T-34s and killed them all. Last night online I dropped an SC-1800 into a formation and killed none desite 2 of them sitting in the blast circle graphic.

bolillo_loco
01-28-2006, 06:16 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Jetbuff:
I'm wondering if you have a lot of experience about bomb blast radii and effects?

The reason I ask, is that I find most bombs in IL-2 to be, well, puny. Indeed, the only bombs that meet my expectation are the 5000kg Russian monster on the Pe-8, the Mistel and the V-1. I believe that tanks require a direct hit because of the absence of any terrain deformation but even so I cannot reconcile a narrow miss by a 1000lb/500kg bomb to the often pitiful damage it inflicts.

However, my expectations can easily be wrong, so I'm hoping you, or anyone else with first hand knowledge on the topic can weigh in. Cheers... </div></BLOCKQUOTE>

I've only a few books that give general statements. The bombs I've seen go off, well I was pretty far away. While I've have seen a few go off, the key word is few. Most of the stuff I got to observe was 155mm and 203mm artillery. If I remember correctly 155mm has 98lbs of HE and 203mm has 206lbs of HE, quite a bit different than GP bombs of 500, 1,000, and 2,000lbs. I mostly fired the stuff, but once on a rare occasion I got to observe it landing. We sometimes co-ordinated with an air strike. One battery's rounds would land, a jet would come in drop a bomb, and then another battery's rounds would land as soon as the jet pulled out.

Sorry, but I probably cannot help you due lack of experience.

Jetbuff
01-28-2006, 06:27 AM
No worries Bolillo_loco, Sensei's stepped up to the plate. http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

Thanks Sensei for the very detailed info. I'm not completely off my rocker then and bomb damage is definitely questionable? A few more questions if I may:

1. Could the difference in effectiveness be a matter of different explosive material being used? i.e. while sill 'dumb' are the Mk8x bombs still the same as their WWII counterparts?

2. If you had the ability to do so, by what order of magnitude would you increase the bomb-blast effects, roughly speaking?

3. Any chance you could save me the trouble and draw a direct comparison between the various Mk-8x bombs and an in your opinion appropriate WWII counterpart?

Cheers...

bolillo_loco
01-28-2006, 06:31 AM
I would believe what WWSensei says simply from my own direct fire experience at old junk tanks. The 203mm howitzer fires a round that has less than half the HE content of the smallest bomb he speaks of, (500lbs). Even with less than half the HE content, a direct hit from a 203mm round or one that landed with in 10 meters would usually flip the tank over, pop the turret, and if none of the this happened the thing was torn up pretty bad, sometimes resembling a junk pile of major appliances. We used to direct fire the M-110A2 from time to time when we went to Ft. Bragg. The Army sure did have a lot more money than we did http://forums.ubi.com/groupee_common/emoticons/icon_frown.gif they had all sorts of neat targets. The tanks looked like 50s to early 60s vintage, but I've forgotten the exact types. M-48s stick in my head, but like I've said, I'm not sure. I rarely took a camera with me to the field, but wish I would have.

I know I've seen what bombs could do. I like the interesting combinations of bombs that the Americans used. I have some pictures of this and will post them when I find them.

p1ngu666
01-28-2006, 06:39 AM
think the vast majority of bombs we use in PF have a 50% charge ratio. 50% of the weight is explosive, rest is casing.

germans had long triggers for some bombs, so that they airburst a few metres above the ground

Jetbuff
01-28-2006, 08:34 AM
I always thought the bomb 'weight' was the weight of the explosive charge rather than gross weight. Interesting...

whiteladder
01-28-2006, 01:19 PM
A did this a while ago. hope the images still work

I dive bombed onto a number of different types of target (I made about 3 trials on each)


SC500 onto unarmoured car targets
http://img467.imageshack.us/img467/9901/sc5008tp.jpg


SD500 onto unarmoured car targets
http://img190.imageshack.us/img190/7093/sd5009tx.jpg


SC500 onto Shermans
http://img495.imageshack.us/img495/9066/shermansc5009lt.jpg

SD500 onto Shermans
http://img124.imageshack.us/img124/6529/shermansd5007gx.jpg

AB500 onto Shermans
http://img126.imageshack.us/img126/8232/shermanab5002du.jpg



On the unarmoured targets there is little to choose between an SC or SD (the Custer bomb hit a similar number of car as it did the in the tank test tests and isn`t a good choice for light targets)

On the armoured targets I found that the SC were slightly better than SD( by about one target per run). Although the AB performed best it is unlikely you will get a target as compact as my test target.

It seem that there is very little modelling of fragmentation effects from the bombs, although the relative explosive content does seem to make a difference.

The Tiger2 should be about the best armoured vehicle in the game, but was as vunerable as the Sherman to bombs. So either the relative thicknesses of armour are not modelled or it just matters how big the bang is, like the ships!

I did a further test on a bunker target and the SC seemed to be the best performer again.

So go for an SC on most targets would seem to make the most sense.

Jetbuff
01-28-2006, 01:23 PM
Yes AB might as well not be in the game. Without troop concentrations, for true area targets it is really worthless offensively.

I always thought SD was for hardened targets and SC for general purpose, but my experience, like yours, has been that SC is better at pretty much everything.

whiteladder
01-28-2006, 01:32 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">I always thought SD was for hardened targets and SC for general purpose, but my experience, like yours, has been that SC is better at pretty much everything. </div></BLOCKQUOTE>


You probally know all this any way Jetbuff, In real life SD was a general purpose bomb that used fragmentation as the main damage mechanisim. SC was also for general purpose but relied on blast. For German weapons the following is true for real life.

The first two letters are the type of bomb.

SC = SPRENGBOMBE CYLINDRICH (thin cased general purpose)

SD = SPRENGBOMBE DICKWANDIG (thick cased semi-armour piercing)

PC = PANZERBOMBE CYLINDRICH (Armour piercing)

AB = Abwurf Behalter (Cluster Bomb)

The the number denotes the weight of the the bomb.

So SC250 is a 250Kg (500lb) thin cased general purpose bomb.

As you go down the list the amount of explosive goes down and the thickness of the casing goes up

SC 55% of the weight is explosive.
SD 35% of the weight is explosive.
PC 20% of the weight is explosive.

I think the problem is in game the armour peicing effect isn`t modelled. It certainly isn`t for ships, the wieght of explosive is what is important. This makes PC a waste of time.

Jetbuff
01-28-2006, 04:23 PM
Thanks Whiteladder. My German is actually appalling so no, I did not know all the details. http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

Yes, it does appear that there is no advantage in the armour piercing variety and blast radius - based on explosive content - is the primary determinant.

Now up above Sensei notes 'flipping' a T-72 tank 20-30m while being 30m off target with a MK82. The MK82 is 500lb (250kg) and not specifically armour piercing from what I understand. It carries "89 kg / 192 lbs Tritonal, Minol II, or H-6" as the explosive charge and that comes to about 40% by weight. That makes it roughly comparable to the SC250/SD250/500lb bomb in game. None of those can even scratch a tank at 30m distance.

Again, with the MK83, at 1000lbs and 40% explosive content by weight, Sensei describes 'tearing off' the turret on a T-72 from 50m which is at odds with my in-game experiences.

Unfortunately, it's not that simple, for one thing, what type of explosive charges were used in WWII and how do they compare to those listed above? Conversely though, a T-72 is a much heavier and stronger tank than most of the tanks we have in-game.


My best guess, true fragmentation and shrapnel are not modelled to save CPU cycles. However, in that case I would argue that the blast radius effect should be increased to allow for that simplification.

Kocur_
01-28-2006, 04:28 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Jetbuff:
I always thought the bomb 'weight' was the weight of the explosive charge rather than gross weight. Interesting... </div></BLOCKQUOTE>

In fact its not neccesarily gross weight either http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif. Usually weights we read are more like "caliber" of bomb indicators. Their actual weights are a bit different, yet very close.
Weight of explosive varies, depending on bombs purpose. The largest percentage is of course for HE bombs, and reaches over 40%. Its lower for HEFrag bombs and lowest for Frag ones and anti -armour. Some of them:
HE
type.............kg.......kg
Mk82Mod1.....241......87
Mk83Mod3.....447......202
FAB-250M54...236......97,5
FAB-500M62...497......209

HEFrag:
type.............kg.......kg
FAB-100M.....121......35
FAB-250-270..279......97

Frag:
type.............kg.......kg
ANM81........125......16
AO-50-100M....96......12,5

Anti armour:
type.............kg.......kg
ANM59A1.......468......132
BRAB-500M-55..517......80

On WW2 UK bombs vs. WW2 tanks read here (http://marinergraphics.com:16080/ww2/smallwoy/GPbomb4.JPG) and following

Jetbuff
01-28-2006, 05:10 PM
Thanks for the link. It's hard to read though, can you verify #3 as being a 500lb (250kg) bomb that missed by 100 feet (~30m) and yet managed to penetrate the turret?

It is also interesting how random the effects are - no blast radius shortcuts there. http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

WWSensei
01-28-2006, 05:51 PM
Increase them? I would say "yes" except they real problem seems to be blast radius and effects. Like I said, it also seems to differ online from offline.

Jetbuff
01-28-2006, 10:20 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by WWSensei:
Increase them? I would say "yes" except they real problem seems to be blast radius and effects. </div></BLOCKQUOTE>
I'm not sure I followed that last bit... could you elaborate?
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Like I said, it also seems to differ online from offline. </div></BLOCKQUOTE>
Although I have not noticed any difference personally, I'll take your word for it. What is the difference btw?

Kocur_
01-29-2006, 04:27 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Jetbuff:
Thanks for the link. It's hard to read though, can you verify #3 as being a 500lb (250kg) bomb that missed by 100 feet (~30m) and yet managed to penetrate the turret?
</div></BLOCKQUOTE>

The bombs were detonated statically, in position they would be in, when hitting ground and put in front and behind of the tank. The target was MkI Cruiser tank, aka A9. And yes, I read #3 as penetration. There were other penetrations too. But we are talking here about light, 12t tank, of max armour thickness of 14mm...

bolillo_loco
01-29-2006, 06:16 AM
U.S. bombs

If I remember correctly, the Americans used a wider variety of bombs in the MTO and PTO. The chart below represents a partial list of American bombs. I believe that there was a special bomb used for cutting rail lines and roads in the MTO. It had something like 70-77% HE content and used a fued delay so that it would go deep underground before it blew up. Used to good effect in Italy due to the rugged terrain. Since the cut couldn't be circumnavigated, it had to be repaired.

http://img.photobucket.com/albums/v358/bolillo_quemado/bomb3.jpg

I've always liked the ordinance carried by American aircraft in the MTO and PTO. It represents a much wider variety, custom bomb combinations, and also external loads for specific targets. Something I think was never or rarely employed in the ETO.

Custom MTO bombs (Field Modifications)

http://img.photobucket.com/albums/v358/bolillo_quemado/bomb2.jpg
http://img.photobucket.com/albums/v358/bolillo_quemado/bomb1.jpg
http://img.photobucket.com/albums/v358/bolillo_quemado/bomb.jpg

Custom MTO bomb loads (Field Modifications)

http://img.photobucket.com/albums/v358/bolillo_quemado/bombextra.jpg
http://img.photobucket.com/albums/v358/bolillo_quemado/bombextra3.jpg
http://img.photobucket.com/albums/v358/bolillo_quemado/bombextra1.jpg

I believe I was wrong about the weights of artillery rounds. I stated that the 155mm had 98 pounds of HE and that the 203mm had 206lbs of HE. I believe that it was the net weight of the entire projectile not the HE content.

p1ngu666
01-29-2006, 09:54 AM
http://en.wikipedia.org/wiki/Blockbuster_bomb

70% ratio would give the 12000lb one, 8400lb's of exposive http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif