KA-50 survives a direct hit from Leopard 120mm AP?

[pyromaniac4002]

If the projectile strikes an empty portion of the helicopter, all it will do is put a hole through it.

 

Can't say I've ever worked on one personally, but I'd venture a guess that there aren't many "empty portions" on a Ka-50. Otherwise, I have some very serious doubts as to the proficiency of those Kamov bureau guys that designed it.

 

For an attack helicopter, a direct hit by any kinetic energy penetrator out of a tank cannon should be no less than devastating. The vast majority of surfaces cover some pretty necessary components that don't take kindly to having their guts shredded.

[Isegrim]

in what respect?

 

 

Kinetic kills with modern penetrators kill and destroy with high internal pressure. Because of the extremely high pressure forces of the round passing through the armor, this heats and pressure kills the crew and nearly every time cooks of rounds. It is not a matter of shrapnel or contact with ammunition. Tanks designed to protect crews have blowout panels to reduce the internal pressure buildup. Russian tanks do not take into account crew survivability. Israel pays great attention to crew survivability in their AFV design.

 

This pressure will build up in every (nearly) closed room that could be penetraded by the tracer, till the maximum pressure this room can stand.

So a Tank can stand this Pressure but not so the Crew.

A Direct hit on an Helicopter will be very devastating.

Edited May 14, 2014 by Isegrim

[Haukka81]

Kinetic kills with modern penetrators kill and destroy with high internal pressure. Because of the extremely high pressure forces of the round passing through the armor, this heats and pressure kills the crew and nearly every time cooks of rounds. It is not a matter of shrapnel or contact with ammunition. Tanks designed to protect crews have blowout panels to reduce the internal pressure buildup. Russian tanks do not take into account crew survivability. Israel pays great attention to crew survivability in their AFV design.

 

This pressure will build up in every (nearly) closed room that could be penetraded by the tracer, till the maximum pressure this room can stand.

So a Tank can stand this Pressure but not so the Crew.

A Direct hit on an Helicopter will be very devastating.

 

 

+1 for this, presure is killer, not shrapnels

[Flying Penguin]

A Direct hit on an Helicopter will be very devastating.

 

Depending on the area it hit and the design. Bear in mind that most (but not all) of the after-armour effects from a SABOT are fragments of armour and round shredding everything inside the tank, as well as the pyrophoric combustion of those fragments due to friction heating during the penetration, not simply overpressure (and of particular relevance to this discussion, overpressure works best when there is a fully sealed vessel to act on that can contain it). Blow out panels are not primarily for dealing with overpressure, they are designed to minimise the effects of ammunition explosions.

 

If there is little to no resistance from armour, it is quite possible for the projectile to fly straight through relatively unscathed as it is the friction and splintering that causes most of the lethal effects. Imagine shooting an arrow through a sheet of paper and you'll have a good idea of what I mean.

 

In a lithe attack bird like the K-50, getting off scot free *should* be unusual (although you can probably identify specific points it could pass through without causing catastrophic damage, the canopy being the most obvious), but on something big and fat like a Hind, there are large areas of empty space that a round could pass through with little to no impedance. Sucks to be the soldier who gets a SABOT round through the face whilst sat in a chopper, but it is perfectly possible to find routes through such a machine which won't cause catastrophic damage.

Edited May 14, 2014 by Flying Penguin

[Bushmanni]

Can't say I've ever worked on one personally, but I'd venture a guess that there aren't many "empty portions" on a Ka-50. Otherwise, I have some very serious doubts as to the proficiency of those Kamov bureau guys that designed it.

 

For an attack helicopter, a direct hit by any kinetic energy penetrator out of a tank cannon should be no less than devastating. The vast majority of surfaces cover some pretty necessary components that don't take kindly to having their guts shredded.

 

Military choppers are designed to have more skin surface area than they would really need to provide the necessary volume for the internal stuff to increase survivability. When you make a hole in the skin the relative size of the hole to the overall structure is smaller and hence reduction in strength is smaller also. You can't prevent penetration against even the weakest projectiles so you need to make the structure hold together even if there are some holes in it.

[Isegrim]

Depending on the area it hit and the design. Bear in mind that most of the after-armour effects from a SABOT are fragments of armour and round shredding everything inside the tank, as well as the pyrophoric combustion of those fragments due to friction heating during the penetration, not simply overpressure (and of particular relevance to this discussion, overpressure works best when there is a fully sealed vessel to act on that can contain it). Blow out panels are not primarily for dealing with overpressure, they are designed to minimise the effects of ammunition explosions.

 

If there is little to no resistance from armour, it is quite possible for the projectile to fly straight through relatively unscathed as it is the friction and splintering that causes most of the lethal effects. Imagine shooting an arrow through a sheet of paper and you'll have a good idea of what I mean.

 

In a lithe attack bird like the K-50, getting off scot free *should* be unusual (although you can probably identify specific points it could pass through without causing catastrophic damage, the canopy being the most obvious), but on something big and fat like a Hind, there are large areas of empty space that a round could pass through with little to no impedance. Sucks to be the soldier who gets a SABOT round through the face whilst sat in a chopper, but it is perfectly possible to find routes through such a machine which won't cause catastrophic damage.

 

 

Yes i Know what you mean. And you are mostly right on that.

But this Pressure will be in every mostly sealed room.

So if you hit the Cargo room of lets say a Mi-8 and its sealed enough maybe the Backdoors come off (not that Catastrophic) or it will look like a exploded barrel (Catastrophic) nobady can say in prior correctly.

 

Also the Blow out panel you think of is only the one above the turrets ammuniton Depot on an M1 or L2.

All others like Crew hatches and emergency exit (L2 Driver) are usefull in both situations.

[Flying Penguin]

Yes i Know what you mean. And you are mostly right on that.

But this Pressure will be in every mostly sealed room.

So if you hit the Cargo room of lets say a Mi-8 and its sealed enough maybe the Backdoors come off (not that Catastrophic) or it will look like a exploded barrel (Catastrophic) nobady can say in prior correctly.

 

There's two things to take into consideration here, firstly most military helicopters aren't that well sealed, at least against overpressure from inside, even if they aren't outright drafty.... We aren't talking about airliners sealed for 35,000ft comfort.

 

Secondly if significant overpressure does occur, the first thing to go will be whatever the weakest pressure-load bearing component, in the case of overpressure in the troop compartment this is probably the door hinges or windows, meaning that a complete disintegration (which would require destruction of load bearing structural elements) is unlikely in the absence of a hit (by round or fragments) on something like the fuel tank. The reason that overpressure works so well in tanks is that they are extremely strong and mostly NBC sealed, meaning there is no easy release for the pressure.

 

Also the Blow out panel you think of is only the one above the turrets ammuniton Depot on an M1 or L2.

All others like Crew hatches and emergency exit (L2 Driver) are usefull in both situations.

 

Correct, they are the only compartments designed with blow out panels. They work because they allow exploding ammunition to direct force away from the crew compartment, which is separated by blast doors. If the blast door is open or the ammo in the turret (e.g. the round currently being loaded) explodes, the crew are simply screwed.

 

If there is overpressure sufficient to pop the hatches (which are not designed to function as blow out panels), the crew are probably already dead from the pressure. Never mind the other after-armour effects like the hail of high velocity burning DU shards that have probably already shredded them.

[Boris]

This is a great discussion, but it's still skimming over the fact that many of the helicopter damage models are flawed and need to be improved.

 

What's the consensus? Are the DCS damage models realistic or not?

[Haukka81]

No they are not And wont ever be (this is game in the end) but i think that damagemodels will get more belivable in future.

[EtherealN]

If the speed of the round is high enough (and it is lol), every little part that breaks off the helicopter will become a "round" on it's own, eacht shard will shatter more material, and all those shards will create more shards and so on.

 

The problem is: what did you hit?

 

If the sabot hits your gearbox, it's game over.

If the sabot hits an empty tail section that, in the case of the Ka-50, pretty much only contains some linkages to rudders... At most you'll sever the tail. And the helicopter will keep flying.

 

A classic example of this was the Hurricane in WW2: if hit by enemy projectiles on the side of the tail, the only thing available to really damage is a couple of wires running to the elevator and rudder. Anything else would just put holes in fabric and possibly place some indentations on the steel trusses inside.

 

In your example, said extra "rounds" might, depending on where you hit, do nothing other than leave the aircraft.

 

Kinetic kills with modern penetrators kill and destroy with high internal pressure. Because of the extremely high pressure forces of the round passing through the armor, this heats and pressure kills the crew and nearly every time cooks of rounds.

 

Attack helicopters are not tanks. To "pressure kill" the crew, you need to hit the cockpit. And if you hit the cockpit with a sabot, pressure is the last thing the crew in question is worried about. ;)

 

This can of course vary between different types of chopper though. But in the case of Ka-50, Mi-24, Mi-28, AH-1, Tiger and AH-64, a hit outside of the cockpit will not cause pressure buildup in the crew cabin. Usually it is only the crew cabin that has a great amount of armor, meaning that if you hit somewhere else said pressure will typically have a lot of other easier ways to go than into the cockpit.

 

This is the thing we're saying: it can be catastrophic for the helicopter. It also can be non-catastrophic. It all depends on where on the chopper you hit, what's inside there, and whether the chopper can fly without it. The Ka-50 is a bit unusual here since it actually can fly even if you remove the tail section. Obviously, most choppers do not have this ability. (Equally obviously, a chopper that is actively attacking you will not display it's tail section, so a hit would be very likely to cause catastrophic damage. But a chopper flying perpendicular to your aim has a large portion of it where hits would not be "catastrophic" in the true sense of the word - though yes, the chopper would most definitely stop doing what it's doing and try it's best to get home.)

 

Military choppers are designed to have more skin surface area than they would really need to provide the necessary volume for the internal stuff to increase survivability. When you make a hole in the skin the relative size of the hole to the overall structure is smaller and hence reduction in strength is smaller also. You can't prevent penetration against even the weakest projectiles so you need to make the structure hold together even if there are some holes in it.

 

Further to that, there are aerodynamic considerations as well. You might be having volumes enclosed by the hull simply to preserve your aerodynamic efficiency. Tail rotor assemblies are a classic here: you need to get proper arm for the anti-torque rotor, and you need the assembly going aft to be aerodynamically sane; but you can't fill it with crap or the chopper would get tailheavy and refuse to fly at all. So even in a chopper with an anti-torque rotor you can very easily get a section that is completely empty aside from some rods and a transmission bar.

 

A hit there may or may not be catastrophic - remember that this is usually not armorplated, just thin steel sheets. That means pressure will vent out through popping the hull sheets before popping anything else, and there also isn't much material to provide spalling. (But of course, if you hit a load-bearing member, or the transmission, it's bye bye chopper.)

 

Yes i Know what you mean. And you are mostly right on that.

But this Pressure will be in every mostly sealed room.

 

Yes, but a helicopter does not have one room at the center for the crew, like most tanks. It has a room at the front for the crew, in the case of an attack chopper sealed off from the rest and being the only part (typically, aside possibly from the gearbox) with real armor.

 

So if you hit the Cargo room of lets say a Mi-8 and its sealed enough maybe the Backdoors come off (not that Catastrophic) or it will look like a exploded barrel (Catastrophic) nobady can say in prior correctly.

 

There's other doors, windows, etcetera. What exactly would happen I'm not sure of, but I am fairly sure that it'll be easier to pop panels and windows than structural members, and the same with accessing the gearbox "room".

 

Finally, do recall that we're talking about a munition made to penetrate armor. That is different to the outer hull of most choppers, aside from crew compartment and possibly gearbox. They do call them "flying tanks", but that is a bit of a misnomer.

[Flying Penguin]

It's not a case of just being realistic or not, the models are pretty good but not perfect. Most run of the mill scenarios are handled pretty well (bearing in mind that you would have build a sim of greater complexity than the whole of DCS to get close to realistic for every edge state).

 

There may be some issues around the handling of large calibre tank rounds, but given the discussion above, the edge cases don't seem so far out of the range of possibilities as to be completely broken. It's not as simple as "SABOT hits helicopter, helicopter becomes a collection of loosely organised pieces, each smaller than a dinner plate".

 

Until DCS gets a full materials and structure simulation engine to process each round impact in turn, there will be a certain level of abstraction, which means there will always be corner cases. The discussion then is whether the results for those corner cases are in the right ballpark (including % chance of no effect), and then fixing them if they are unreasonable.

 

In summary, good but room for improvement.

Edited May 14, 2014 by Flying Penguin

[Isegrim]

There's two things to take into consideration here, firstly most military helicopters aren't that well sealed, at least against overpressure from inside, even if they aren't outright drafty.... We aren't talking about airliners sealed for 35,000ft comfort.

 

Secondly if significant overpressure does occur, the first thing to go will be whatever the weakest pressure-load bearing component, in the case of overpressure in the troop compartment this is probably the door hinges or windows, meaning that a complete disintegration (which would require destruction of load bearing structural elements) is unlikely in the absence of a hit (by round or fragments) on something like the fuel tank. The reason that overpressure works so well in tanks is that they are extremely strong and mostly NBC sealed, meaning there is no easy release for the pressure.

 

 

 

Correct, they are the only compartments designed with blow out panels. They work because they allow exploding ammunition to direct force away from the crew compartment, which is separated by blast doors. If the blast door is open or the ammo in the turret (e.g. the round currently being loaded) explodes, the crew are simply screwed.

 

If there is overpressure sufficient to pop the hatches (which are not designed to function as blow out panels), the crew are probably already dead from the pressure. Never mind the other after-armour effects like the hail of high velocity burning DU shards that have probably already shredded them.

 

 

I see you are talking about the M1. DU is not used in L2.

 

If its possible the Damage model of the Helicopters have to be updated. especialy Oh-58 where vikhrs do no Damage or they simply Glitch through the Helicopter.

[NineLine]

This is a great discussion, but it's still skimming over the fact that many of the helicopter damage models are flawed and need to be improved.

 

What's the consensus? Are the DCS damage models realistic or not?

 

 

Damage models need some love, this was stated by a Dev some time ago. If you have seen the work that VEAO are doing with their Hawk and damage modelling, it can always get better... seems they are stepping it up here.

[Flying Penguin]

I see you are talking about the M1. DU is not used in L2.

 

If its possible the Damage model of the Helicopters have to be updated. especialy Oh-58 where vikhrs do no Damage or they simply Glitch through the Helicopter.

 

The tungsten penetrators used by L2 operators will still be pretty hot after coming through the armour, friction heating will see to that. The DU used in American and British rounds will combust when it penetrates, and that will increase the damage they do, but in the context of helicopters, neither round is likely to get that hot, if simply because there isn't enough armour thickness to work on, making the distinction somewhat academic in this discussion.

 

It is absolutely true that the damage model could be more detailed (and things like glitching through should be fixed asap), but an improved model will not necessarily turn tank rounds into guaranteed one-hit kills.

[EtherealN]

Also, a more detailed damage model might do nothing to fix "glitching".

 

"Glitching" is a case of not detecting the event at all. Having the "event" be more detailed does nothing if the "event" function is never called at all. So yeah, those are different things. Always more to do. :)