.50 vs 20mm

[lobbie111]

that was not really a serious answer, hopefully I can get the power usage down to a standard army battery well for the radar anyway, and fair point about the misty and fog scenario so it might be a good idea to slave the AESA radar to the gun system.

As ive mentioned in my last post about the multiple shot system I may have not made that clear enough. Basically a system whereby a bunch of metal storm like grenade launchers distribute on every side of the vehicle if there are two or more threats in the vehicles vicinity.

Although a question has aroused my mind, would a small AESA radar say 30-60cm be sensitive enough to detect small arms fire?

 

[Wooki]

You took your time getting here, I dropped hints days ago.....

I am not knowing.:unknown

actually, the thing you want to do is reduce power consumption issues - not increase them by adding extra electronic cooling systems.

that may mean using a peltier solution, but I'm not aware of any milspec peltiers.

processor cooling is better served by smaller and smarter coding practice etc..... eg, ASM/ADA may not be elegant, but its a hell of a lot more efficient than microsoft bloat C+ etc......

Exactly. But if your procurement cycle is willing to clean up the slop created by COTS, then you will fnd Java and C++ creeping back into any system you develop.

How about putting the processor of the APS into the FCS compartment of a modern AFV?
This is better shielded against heat und many modern vehicles already feature air conditions for their electronics.
Or does it have to be in one package so that it can be easily installed and removed?

I agree that explosives shot into the direction of the incoming missile threat are the better solution.
5.56/7.62mm flies a long way (Not to talk of 20mm) and can be a much too big risk for other troops in the area.
Nobody who is sane would advertise to fire rounds nearly randomly into every direction.

That is fine to begin with, but as the ambient temperature increases you will find your vehicle not being able to perform as required. In other words the FCS compartment might be able to handle it, but you had better test it before you place it in, as it is adding stress to the systems.

For example; you can't just go plug in any new night vision equipment into a tank as it might get too hot. I think our Indian friends have discovered this in more ways then one.

12.7 or 20mm doesn't really matter, as the ideal projectile you would use for this application is a smart round or the "smart bullet" one shot, one kill and work is well underway for that capability to be contained within 12.7mm caliber.

Its what do you use in the mean time that is the question? In that case I would suggest a 20mm with a timed fuse and use the cumulative KE generated by the projectile and the incoming nasty to defeat the threat.

Although a question has aroused my mind, would a small AESA radar say 30-60cm be sensitive enough to detect small arms fire?

The answer is "today, yes, you could probably do it." But my natural curiosity is why would you want to use AESA when there might be something more applicable to the application that Australians are good at?

Or in Iraq-campaign speak, shift your system to the left of boom. E.g say if you combined the proposed AESA system with a mod of a sniper sound detection system. Sound, you say? Yes, sound can detect things like people carrying RPGs before they fire their weapon. It could also detect 3 people in a crowd running towards you (doppler effect) when visually you can't make out harry from margaret.

In fact, this kind of general overlook of your immediate surroundings is much like how weather radar is used to detect wind shear in a storm system. The crowd (in this case) is the storm and sound deliniation is becoming sophisticated enough to detect patterns in the storm (such as a person running towards you).

That kind of proactive system is inherently a lot more useful then just an APS by itself.

just my 2 c

cheers

w

 

[lobbie111]

With the comment about small arms fire is that, if it could pick up and my system would verify that as a target, it might start to open fire at the small arms fire... It would be good however if the gun fired back at the infantry because of the tradjectory of that small arms fire. But on the whole your just wasting ammo...

And Wooki what you just stated to me is more in the situational awareness category not that you couldn't ad that role to the system, but now I'm bordering on is creating an entire combat system for a vehicle which isn't out of my bounds but a little complicated on my part. I could however do it in sections the ADS not the situational awareness system next etc...

 

[Wooki]

With the comment about small arms fire is that, if it could pick up and my system would verify that as a target, it might start to open fire at the small arms fire... It would be good however if the gun fired back at the infantry because of the tradjectory of that small arms fire. But on the whole your just wasting ammo...

And Wooki what you just stated to me is more in the situational awareness category not that you couldn't ad that role to the system, but now I'm bordering on is creating an entire combat system for a vehicle which isn't out of my bounds but a little complicated on my part. I could however do it in sections the ADS not the situational awareness system next etc...

This is fun.

Yes, design your system from the get go to be plug and play with other systems. You need to actually develop your own market awareness. What other people are doing and what the customer wants. The later is really hard for me to fathom with regard to the Australian Army, so I defer to others.

But my thought on protection of a vehicle is Situation Awareness and design.

For example: The people who are trying to kill you are people (not bullets) and as people they have to get motivated to do it. If you are low tech, that means you have to get seriously motivated as you are probably going to do something like throw a bomb, etc. that means it is much more useful to a TC to know where that motivated enemy is coming from.

re: design: it is much simpler to cut down your 4x4 by 6 inches (lower the silhouette) and thereby reduce the risk of being hit by an RPG by x% at Y range.

But in sophisticated environments (such as a crowd) you use multiple systems integrated in one suite. You use the AESA ( in your case) as a trip wire to fire the counter measures. But hopefully, you have designed the suite well enough (That's an integrators job for the main part) that the APS (as you see it) is never used.

cheers

w

 

[Chrom]

I always wonder how effective is the APS against a Rocket?ATGM attack from very close range (less then 100 metres). will the system have enough time to react?

Yes. Most systems can intersept RPG missile fired from less than 50m.

- If you're using AESA, then the fast scan rate will make the enemy ESM effort rather difficult. beside, the AESA can also serve as a jammer/target tracking at the same time. so you have extra bonus there. with Radar targeting, smoke screen and foggy condition will be useless to protect the target. but i wonder if there's any AESA system small enough to fit inside tank..

Yes. AESA can enjoy modular design and dont need all modules placed in same backet. So basicaly you can place small modules here and there all around tank and they will work.

 

[Waylander]

That is fine to begin with, but as the ambient temperature increases you will find your vehicle not being able to perform as required. In other words the FCS compartment might be able to handle it, but you had better test it before you place it in, as it is adding stress to the systems.

For example; you can't just go plug in any new night vision equipment into a tank as it might get too hot. I think our Indian friends have discovered this in more ways then one.

12.7 or 20mm doesn't really matter, as the ideal projectile you would use for this application is a smart round or the "smart bullet" one shot, one kill and work is well underway for that capability to be contained within 12.7mm caliber.

Its what do you use in the mean time that is the question? In that case I would suggest a 20mm with a timed fuse and use the cumulative KE generated by the projectile and the incoming nasty to defeat the threat.

I never thought of putting that onto a vehicle without testing if the current cooling system for the FCS compartment can cope with the added stress of some more processors.
But still I think upgrading the already installed air condition for the FCS compartment should be easier than cooling a completely independent APS.

As for time fuzed rounds. I heard that smaller rounds are in the pipe but currently IIRC 30mm is the smallest round which can be equipped with a usefull time fuzing capability and payload.

Not to forget that such a gun system is huge + the needed ammo.
Compared to the current russian and israeli systems as well as the german and US systems which are nearing finalization I don't expect it to end up very good.
Height, dimension and weight are serious matters for an AFV and putting a monster APS with a huge gun system onto an AFV is maybe causing more problems than solving problems.

 

[lobbie111]

Well my original idea was to go with the XM307/312 as it has smartshells and the radar can directly translate the data onto the shells, additionally the calibre can be changed to a .50 whenever they want, but the only problem is that it has a slow rate of fire...not convieniant in situations where multiple rapid shots are required.

And I think we can all agree that Prevention is Better than a Cure. But as I am not deigning a vehicle just an additional 'Plug and Play' system I don't see how telling me to lower the profile of the vehicle or provide a situational awareness for the vehicle is going to help...

Now as to the AESA radar there will be multiple bolt on small panels which will provide total coverage. The weapon will link straight into the existing weapons mount although it has to be remote controlled. The Airburst grenades will mount straight into the existing grenade launchers or new ones will be mounted on the vehicle.

 

[Wooki]

Not to forget that such a gun system is huge + the needed ammo.
Compared to the current russian and israeli systems as well as the german and US systems which are nearing finalization I don't expect it to end up very good.
Height, dimension and weight are serious matters for an AFV and putting a monster APS with a huge gun system onto an AFV is maybe causing more problems than solving problems.

I thought lobbie was looking at a metal storm system? Makes more sense and it would probably (hopefully) aid a guided system. So basically we are looking at some sort of guided arena system here, right?

Oh, here is an idea; If you go with metal storm then you change the ballistic characteristics of the projectile right?... You know, go the whole way and go with a flying torus (donut) that spins out a blown fiber polyethelene net to catch the incoming threat, or something like that? Be easy enough to do and would make the system less lethal if it went off by mistake. so instead of a 30 mm, or 40 mm projectile, you have (for all intents and purposes) a 200mm plate intercepting the threat, because it is expanding in diameter.

This is all open source non-lethal stuff, but might be well suited as metal storm is a pain in the ass the way you have to modify ammo to shoot out of the thing...So if you are going to have to modify your ammo, then try and turn that into a positive and shoot something that an ordinary gun can't.

cheers

w

 

[lobbie111]

I was more thinking a metalstorm system for the grenade launcher so when an enemy launches salvos of rpgs the grenades go off close to the tank, no infantry in their right mind would be standing right next to a tank if they're not doing anything with it i.e. on the intercom phone system etc.

[ame="http://www.youtube.com/watch?v=zx_9_RgMPCE"]YouTube - Metal Storm Mortar[/ame]

thats what I weas thinking in terms of grenade launcher system (not the whole thing of course just the way the ammo is stacked)

so your eliminating any risks of friendly fire when all the projectiles muzzle velocity dissipates after 5m.

But in terms of urban combat the system can be set to use the gun on low lying targets whilst the grenade system uses the upper teir for multiple threats for example your in a convoy passing through some 3-4 story units in baghdad four RPG's come at your vehicle 1 from the second story on the left two from the third story on the right and one directly at the front of the vehicle. The one coming directly aty the vehicle is shot by the weapon and the grenades go off at the top neaturalising all three rounds and no injury to the troops on either side of the vehicle.

Oh by the way the vehicle external dimensions are not affected...nor are the armarment, the system uses either the primary or secondary weapons system of the vehicle.

 

[Awang se]

Oh, here is an idea; If you go with metal storm then you change the ballistic characteristics of the projectile right?... You know, go the whole way and go with a flying torus (donut) that spins out a blown fiber polyethelene net to catch the incoming threat, or something like that? Be easy enough to do and would make the system less lethal if it went off by mistake. so instead of a 30 mm, or 40 mm projectile, you have (for all intents and purposes) a 200mm plate intercepting the threat, because it is expanding in diameter.

Can you make the net heavy and fast enough so that it may overcome the momentum of the incoming projectiles?

Well my original idea was to go with the XM307/312 as it has smartshells and the radar can directly translate the data onto the shells, additionally the calibre can be changed to a .50 whenever they want, but the only problem is that it has a slow rate of fire...not convieniant in situations where multiple rapid shots are required.

the problem remains. the shell, smart or no smart will throw fragments in every directions when it explode, thus endangering the accompanying infantry. you must use some sort of directional blast. for example, ARENA system employed an explosive charged that throw a directional fragment blast upward away from the infantry. furthermore, the blast of the intercepted missile may spew fragments as well.

FYI, i've already think of several manportable weapons design that may be able to overcome Active protection system.

 

[lobbie111]

the problem remains. the shell, smart or no smart will throw fragments in every directions when it explode, thus endangering the accompanying infantry. you must use some sort of directional blast. for example, ARENA system employed an explosive charged that throw a directional fragment blast upward away from the infantry. furthermore, the blast of the intercepted missile may spew fragments as well.

The XM307 is duel feed, I never specified what ammunition I was going to use, For a directional blast all I have to do is modify existing shell designs for that caliber plus the XM307 is duel feed so I can put in standard ammo as well. Although the fact is that that type of shell would probably be very effective against light armour and infantry.

 

[Chrom]

Can you make the net heavy and fast enough so that it may overcome the momentum of the incoming projectiles?



the problem remains. the shell, smart or no smart will throw fragments in every directions when it explode, thus endangering the accompanying infantry. you must use some sort of directional blast. for example, ARENA system employed an explosive charged that throw a directional fragment blast upward away from the infantry. furthermore, the blast of the intercepted missile may spew fragments as well.

.

This is much less important than it sounds. HEAT explosion itself cause much more splinters than any interception charge. Basically, some argument with ERA, even 1st gen ones - if someone is close enouth to be affected by ERA, he will be surery affected much more by explosion of HEAT warhead.

 

[lobbie111]

f someone is close enouth to be affected by ERA, he will be surery affected much more by explosion of HEAT warhead.

There are only certain times when infantry are actually that close to a vehicle...(Disembarking/Embarking etc.) so there is no reason for infantry to be close to a vehicle except for urban operations. The infantry should be well clear of the vehicle anyway so I don't see why this will be a problem.

 

[Wooki]

Can you make the net heavy and fast enough so that it may overcome the momentum of the incoming projectiles?

Why would you want to do that? Think about it. You let the KE of the penetrator work for you and wrap the expanding projectile around it. This in turn makes any ceramic applique and/or ballistic cloth work better. It makes it easier to "catch" the incoming penetrator. It would also render an ATGM ineffective.

cheers

w

 

[lobbie111]

Can someone help me here, could you in theory create an EFP that on deteonation has so much pressure that when the warhead of say the RPG detonates it conforms into the shape of the EFP's blast? Shrapnel and everything are directed away from anything because of the way the blast is formed?

 

[Wooki]

Can someone help me here, could you in theory create an EFP that on deteonation has so much pressure that when the warhead of say the RPG detonates it conforms into the shape of the EFP's blast? Shrapnel and everything are directed away from anything because of the way the blast is formed?

I am not sure what you are saying. Do you mean firing an EFP across the path of a shaped charge stream? If so, its better to use another shaped charge, say of water as a liner or magnesium alah Sydney Alford.

have to go

cheers

w

 

[lobbie111]

I am not sure what you are saying. Do you mean firing an EFP across the path of a shaped charge stream? If so, its better to use another shaped charge, say of water as a liner or magnesium alah Sydney Alford.

have to go

cheers

w

Yeah I wasn't sure anyone would so i drew a picture on paint...

 

[lobbie111]

It failed to upload sorry about that folks...It won't support the file type anyone know a way around it?

 

[Waylander]

Upload it at www.imageshack.us and post the link.
It works with paint files.

 

[kato]

MS Paint can save files compressed to jpeg, or also as gif. Both are recognized.