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In BF2, the SF class carries around several explosive devices, they are filled with C-4. In this thread, I am going to try and convince the developers to reduce the power of their C-4 charges to purely realistic values. Below, you can find my calculations to find the explosive force of the C-4 used in the game. (SCROLL TO THE BOTTOM TO SKIP THE MATH!!!)

The RC-90 detonator is about 23 cm tall. Using that measurement and this picture: http://files.ea.com/downloads/eagames/o ... onator.jpg
We can calculate the volume of the charge that the player uses.

Volume = LxWxH
V:C4 = 20x18x11.5 cm
V:C4 = 4140 cm3

So, the volume of the C-4 charge in BF2 is about 4140 cm3.
We know that RDX is the primary explosive filler in C-4.
RDX's density if 1.76 grams/cm3. With this, we can find the bomb's RDX mass.

Mass of Bomb's RDX = 1.76g x 4140cm^3 = 7286.4 grams

This would be the bomb's weight if it was 100% RDX, but we know that C-4 is a mixture of RDX and a plasticizer. RDX makes up 91% of the C-4's mass. So, we take 7286.4g x 0.91 = 6630.624g. This is the bomb's approximate amount of RDX: 6630.624 grams.

"Detonation is a process of supersonic combustion that involves a shock wave and a reaction zone behind it. The shock compresses the material thus increasing the temperature to the point of ignition. The ignited material burns behind the shock and releases energy that supports the shock propagation. This self-sustained detonation wave is different from a deflagration that propagates with a subsonic speed and without a shock. Detonations generate high pressures and are usually much more destructive than deflagrations."

RDX's velocity of detonation at a density of 1.76 grams/cm^3 is 8,750 meters per second (m/s). With this information, the detonation force can be found using more formulae. After this, you can use another formula to determine the size of a charge needed to penetrate the armor of an M1A2 Abrams as depicted in the game.

Using the formula (P = R^3*K*C), where:
P = Exp. Required (kg
R = Breaching Radius (m)
K = Material Factor (kg/m^3)
C = Tamping Factor (m)

On the sides of the M1A2, the armor is made up of ceramic blocks set in resin between layers of conventional armor such as steel. The breaching radius of that armor is about 300mm (0.3 m). The material factor is about 27 080 kg/m^3 (DU+Steel+Ceramics). The tamping factor is ruled out since in the game, you don't cover the explosive charge with anything.

P = 0.3m^3 * 27080kg/m^3 = 731.16kg of C-4

731.6kg = = 1612.9 lbs.

So, the final calculation shows that the player would need a 1612.9 pound package of uncovered C-4 to completely destroy an M1A2 Abrams. The player in the game has a bomb that weighs about 14 pounds!

CONCLUSION!
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The power of the SF infantry's C-4 charge in PRMM against the M1A2 tank, needs to be scaled down by a factor of 115 to the side and frontal armor. The tank needs to be vulnerable to engine destruction if the player places C-4 on the engine exhaust of the tank, thus stopping the tank. Hummvees, light vehicles, and infantry should still be very vulnerable to C-4 packs, as they do not have 300mm thick armor. That's my suggestion.

where the hells DrZero when you need him?

I said this a while back but not in detail. I read about a guy from the US army who had used full standard issue C4 packs on lots of things and the power was no where near the damage to destroy a tank with 2 charges.

ekstasis wrote:In BF2, the SF class carries around several explosive devices, they are filled with C-4. In this thread, I am going to try and convince the developers to reduce the power of their C-4 charges to purely realistic values. Below, you can find my calculations to find the explosive force of the C-4 used in the game. (SCROLL TO THE BOTTOM TO SKIP THE MATH!!!)

...

CONCLUSION!
---------------

The power of the SF infantry's C-4 charge in PRMM against the M1A2 tank, needs to be scaled down by a factor of 115 to the side and frontal armor. The tank needs to be vulnerable to engine destruction if the player places C-4 on the engine exhaust of the tank, thus stopping the tank. Hummvees, light vehicles, and infantry should still be very vulnerable to C-4 packs, as they do not have 300mm thick armor. That's my suggestion.

Yes C4 damage will be lowered. We spent more time tweaking infantry than vehicles. Unfortunately, vehicles use a single default defense material against splash damage, so we are unable to do make one area of a tank more susceptible than another. It may still be possible, but will take more creative thinking.

In any case, how many packs of C4 do you think it should take to destroy a tank?

how should we destroy a tank instead of?

im a big fan of reality - but we also need to say it needs up to 4 men to use a tank......
if u need 4 men to use a tank in game - change the power of my C4.......

[R-DEV wrote:Paladin-X]

ekstasis wrote:In BF2, the SF class carries around several explosive devices, they are filled with C-4. In this thread, I am going to try and convince the developers to reduce the power of their C-4 charges to purely realistic values. Below, you can find my calculations to find the explosive force of the C-4 used in the game. (SCROLL TO THE BOTTOM TO SKIP THE MATH!!!)

...

CONCLUSION!
---------------

The power of the SF infantry's C-4 charge in PRMM against the M1A2 tank, needs to be scaled down by a factor of 115 to the side and frontal armor. The tank needs to be vulnerable to engine destruction if the player places C-4 on the engine exhaust of the tank, thus stopping the tank. Hummvees, light vehicles, and infantry should still be very vulnerable to C-4 packs, as they do not have 300mm thick armor. That's my suggestion.

Yes C4 damage will be lowered. We spent more time tweaking infantry than vehicles. Unfortunately, vehicles use a single default defense material against splash damage, so we are unable to do make one area of a tank more susceptible than another. It may still be possible, but will take more creative thinking.

In any case, how many packs of C4 do you think it should take to destroy a tank?

I read that issued C4 comes in strips of 9 inches by 3inches and 1inch thick (averagely). so the packs in BF2 currently look like you could fit 6 packs of C4 in there. 2 BF2 packs = 12 packs of C4 which is enough to stop a tank but obviously the packs are not realistic.

i say 2 to disable 3 to blow up

it would be nice if putting a single pack on say the treads or engine could disable but a single park on turret doesnt but from what paladin said it doesnt sound possible

i dont agree that 2 to disable and 3 to blow it up. if you dont blow the tank in to somthing ugly its not dead unless the crew are (if its not moving what says its guns arnt working...). You must remember that tanks are made or equipped in field with explosive armor - C4 is an explosive.... so has little effect on a tank. unles the charge was placed somwhere that the energy cannot escape from. For example a charge does more damage if it blows up under an object then it does on the top of an object.
Also i would really like to see hitboxes applied to tanks so you can blow of the tracks and mabe other cool things.

by disabled i mean the tank cant move the turret can turn and guns can fire it just cant move its treads

no i agree with alot of what you said solo i think it should be that the treads stop moving but it doesnt blow and should stay that way for a while

Well, for all of you in this thread asking how many packs it would take to completely blow up a tank in real life, I answered that in my original post:

So, the final calculation shows that the player would need a 1612.9 pound package of uncovered C-4 to completely destroy an M1A2 Abrams. The player in the game has a bomb that weighs about 14 pounds!

It would take 115 "BF2-sized" C-4 packs to totally blow up an Abrams, if they were all placed on one spot on the front or side armor.


REMEMBER! Rockets and shaped charges work totally differently than C-4 packs do, shaped charges such as RPG-7's and the missiles in the game, can disable an Abrams easier than C-4 packs, since the shaped charge in the missile puts so much pressure on a quarter-sized circle of the armor. C-4 packs will send most of the force upward and outward into the air.

Tanks in BF2 don't have a period where they cant drive but can still fire. If you notice, you can keep driving until your health slowly runs out and it explodes.

Which is very unrealistic. Also older tanks once the power supply was broke would require manuel turning of the turret via a crappy crank inside. Allthough im pretty sure there is an internal power supply just for the turret so if the engine is gone the turret can still function as it did before.

Also i totally agree with you about the C4's effectiveness against MBT's. The artcle i read the guy and his squad had to hammer in some fence posts to rig up barbed wire around there camp. The sledge hammer snapped and it was jammed in the head so he dug a 1 foot hole and moulded a charge around the head of the sledgehammer - placed a charge and some wire and blew it up. The wood was totally gone and he said the hammer head was untouched to which they then replaced the handel.

What about c4 effectiveness vs other vehicles? T-90, Type 98, APCs, Bradley, the other anti-air vehicles, humvees, planes, helos?

AAVs, and APC mostly have thin armour, to protect against 12.7mm and lower caliber rounds. Bradlies on the other hand can withstand rounds up towards 30mm. 1 C4 can definately destroy/disable those lightly armoured vehicles.

I think its only tanks that come with ridiculasly thick armor and explosive reactions and or specially weaved - layered armor.
Allthough like the guy mentioned abotu shaped charges could be one way to go against weaker armor allthough not a tank.

Allthough air vehicles im would be much much easyer to blow up since the airframe is fragile and the same rule is applyed with ships and boats etc. The hulls/frame are in delicate balance with each others weight and if it is also disturbed by forces (water pressure, air pressure depenging if its water or air) play a large role in the damage caused.

I watched a documentary on explosives once and a guy turned an old boat over and placed a lump of c4 on the top, wired it up and blew it up. No damage just a burn mark. The guy then placed a lump on the boat hull again and flipped it over in to the water and blew it up. The radious of the hole was about 4 feet.

I think when somthign explodes if it cant escape outwards then it does the damage and thats how shaped charges use, all the pressure goes one way.

Vehicles containing 'soft body' humans would be easily stopped with one C4 simply because it would be enough to kill all the people allthough i dare say the humvee would stil be driveable.

Im gonna have a look to see if there is any articles on explosives and various materials. post later if i have anything.

Here are my thoughts on C4 vs tanks:

C4 should disable a tank if a pack is placed on the engine.
Otherwise, no damage at all, unless it is possible to blow off the turret or cupola, but i don't think bf2 engine can do that...

this is from the same viewpoint as tank rounds either penetrate armor or dont, 100 or 0 kind of thing, no ' it takes two shots to the front to kill an abrams from a t 90..."