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  • 2 weeks later...

   Interesting link was posted on otvaga.


   "Raam Segol" soft-kill APS from late 1990s.


   At the end of the 90s, the Nakhshol tank company operated in the 71st battalion of the 188th brigade in southern Lebanon. The company was stationed at Forward Stronghold Rehan in the north of the security zone and was tasked with testing the Raam Segol (Purple Thunder), a new active protection system for tanks.

   The company was secret, so the name "Nahshol" was not heard by everyone, and photos of the system were also not published officially, but they still leaked into the international press, especially when leaving Lebanon in 2000, like this photo:





   Now the Raam Segol system and the Nakhshol company have been declassified, and Asaf Kamera's report was released on ynet, including the videos filmed then and the current interviews with the participants: https://www.ynet.co.il/news/article/B100y9QDLv

   According to the report, the company was established at the end of 1996, the main period of its activity is 1999-2000.
   Unlike the later Meil Ruach APS, Raam Segol did not include kinetic countermeasures and was limited to optoelectronic suppression, soft-kill. The system detected the launch of the ATGM, gave a signal to the crew, turned the gun in the direction of the threat and set up an aerosol curtain with the help of standard and additional smoke grenade launchers.
...the reason for which company was in Lebanon did not actually happened: the use of anti-tank systems against tanks with Raam Segol APS and the use of the Raam Segol system in real combat situation. Therefore, no real combat tests of the system took place.







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About 20 years ago I was sent photos, out of the blue, of Merkavas with the experimental Purple Thunder  active defence system and an older, bulkier set up which I have never found out the name. I tore the photos into very small pieces and never mentioned them in any of my articles. Now, it seems, Purple Thunder has been declassified 

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  • 2 weeks later...

If I remember correctly it's just a 12,7 mm mounted directly on the gun assembly and is controlled by the gunner.

Give a bit more range, and firepower than the coax 7,62 and the gunner sight allow to make full use of the range of the 12,7.


The American then used the same solution for the TUSK kit of their M1:



It cannot move independently (horizontally or vertically), it's just fixed to the gun.

In essence it is an externally mounted coax, which has the advantage of not taking space inside the turret but then you to have get out to reload it.


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5 hours ago, Wiedzmin said:

you get length of module, not LOS.


Point taken. However it's a complex matter on the Mk4. Firstly on other images showing "vertical slices" of the turret modules, the actual LOS thickness of the armor is mostly maintained across the height of the turret internal volume. Besides that, the inner "empty triangle" in between the armor should be accounted for as well. And in addition we have very thick turret walls (judging by eye the seem to me like 20-30cm in thickness).  

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4 hours ago, alanch90 said:

in between the armor should be accounted for as well.


4 hours ago, alanch90 said:

And in addition we have very thick turret walls

lol what ?




sides 50-60mm MAX, thats why side modules are so thick, to get any protection for this "anti-rain" base protection


gun embrassure assembly 250-300 in thickest part, and thats all, pretty weak turret 







and frontal modules is much thinner than side, and with 90% chance have same concept as previous Mk's - KE protection with steel at frontal part + NERA pack, and NERA only on sides 







and if this is a frontal parts, than it's even less thickness 



in the end Mk.4 is just a attemp to get rid of Mk3 chaotic construction, more uniform protection with less weakned zones, but basic concept is a bit stupid, so you get what you get...

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7 hours ago, alanch90 said:

.Besides that, the inner "empty triangle" in between the armor should be accounted for as well.


Not really. It applies to only half of the turret height. By counting the hollow space inside thr turret, armor thickness becomes extremely inhomogenous.



Not counting the hollow space but understanding that it is a side-effect of the necessary slope for achieving the desired level of protection shows that armor thickness is homogenous along the height of the turret.


Overall armor thickness is not impressive. Very much comparable with other/old MBTs.

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16 hours ago, SH_MM said:


Not really. It applies to only half of the turret height. By counting the hollow space inside thr turret, armor thickness becomes extremely inhomogenous.

If the empty triangular channel is a byproduct of the module geometry and not a needed feature to achieve the required protection level, then i have to conclude that the vast majority of the vertical aspect (at least at the turret side, i will make another estimation like this for the front module) maintains a module LOS thickness of no less than around 480mm not accounting for the side turret wall (50mm RHA?). That by itself is very thick (for comparison M1A2 has around 350-400mm including the side turret backplate/wall).



Another matter entirely is estimating how that thickness translates into practical protection. One thing is certain, the side modules are SLERA (and perhaps the front too, the ones at the UFP are NxRA since they have no warning signs of containing explosives). In the 2008 Rafael patent on SLERA and NxRA (shared on this very forum) both types are described as having comparable volume/mass efficiency to ERA but also being capable of sustaining multiple shots (though not as many as NERA). All the pictures we have seen about damaged Mk.4s point that the "multi hit capability" at least against ATGMs is very limited. But alas, we may be looking at a very high protection effectiveness (in terms of RHA equivalency) indeed.



Small addition: If the 480mm represents the actual SLERA and its sloped back at 60 degrees (of which i'm very sure of), then the actual thickness of the SLERA is 240mm. Take that and slope it to 75 degrees, which is the angle of the front turret module, and you get around 920-930mm. Add to that a probable empty triangular channel of 160mm and we get 1080mm of module LOS length which is surprisingly close to the 1079mm that i estimated yesterday and also virtually the same figure that others have estimated. So, right now i´m pretty confident that the front LOS is 920-930mm of SLERA + (depending of the vertical point) up to 160mm of air + around 250-300mm RHA . That's a lot of armor.

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3 hours ago, VPZ said:


You can't say that for sure until you see this module.

Well we have seen both sides of UFP modules and there are no "warning-eplosives" signs. Makes sense to not have explosives right above the engine. Besides Mighty_Zuk (BTW, why was he banned??) confirmed that to me.

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1 hour ago, alanch90 said:

Well we have seen both sides of UFP modules and there are no "warning-eplosives" signs. Makes sense to not have explosives right above the engine. Besides Mighty_Zuk (BTW, why was he banned??) confirmed that to me.

   Being a dick towards admin/mods and then literally asking for being banned isn't best way to interact with people.

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2 hours ago, alanch90 said:

Well we have seen both sides of UFP modules and there are no "warning-eplosives" signs. Makes sense to not have explosives right above the engine. Besides Mighty_Zuk (BTW, why was he banned??) confirmed that to me.

Too bad. He was the only insider in this thread, and one of the best on this forum.

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