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29 minutes ago, Laviduce said:

Thank you ! But is block A a fuel tank or a special armor block. I treated it as a special armor block(s).

073539cxs7dob79vt6dxud.jpg

Simply translate the words into English, hope it will help. 

9S2JFZR.jpg

Another figure, posted by Wiedzmin in a thread on otvaga, shows the fuel filling port of front fuel system unit. 

 

According to a video record,

about JGSDF tank training in US, they refuel a Type-10 MBT on a fuel filling port of similar location. I assume they both have similar arrangements. 

 

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it's strange, report says that hull special armor weight 1249, so "A" part on scheme can't be fuel cell ? but without big fuel cell how far type90 can ride ? 

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3 minutes ago, Wiedzmin said:

it's strange, report says that hull special armor weight 1249, so "A" part on scheme can't be fuel cell ?

 

There might be some sort of spaced metal plates inside the fuel cell to improve its effectiveness as armor.

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22 minutes ago, Wiedzmin said:

it's strange, report says that hull special armor weight 1249, so "A" part on scheme can't be fuel cell ? but without big fuel cell how far type90 can ride ? 

type90 are mainly used in Hokkaido defense, i think they don't need too mach fuel.

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33 minutes ago, Wiedzmin said:

it's strange, report says that hull special armor weight 1249, so "A" part on scheme can't be fuel cell ? but without big fuel cell how far type90 can ride ? 

With a internal fuel capacity of 1272 litre, Type-90 can travel about 300-340 km.

Type-74 in comparison, can travel about 400 km when equipped with external fuel container. 

Exact data could depends on terrain and weather, especially in winter condition. 

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9 hours ago, Collimatrix said:

 

There might be some sort of spaced metal plates inside the fuel cell to improve its effectiveness as armor.

Hmmm!!! Just like Fuel Cell B, that surrounds the ammunition , fuel cell A could be a composite array that uses diesel fuel to complement its protective properties.

 

Type90_fh_fc.jpg.532e4aa1e4085c88e3b048e

Note: The front hull special armor is supposed to have  a mass of 1249 kg!

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Fuel Cell composite armor is believable....

And talk about fuel cell armor,i've heard an interesting design. Few years ago Chinese enginner has built a special fuel cell composite armor which uses Oplot-M ‘s design as reference.

1Y0g7wH.png

With the similar principle, filling diesel in the cell wall structure actually worked like an ERA and successfully weakened a HEAT testing warhead which capable of penetrating 280mm to 160mm by only 20mm thick of fuel cell armor.

8QO0HpN.jpg

rLbchQG.png

TmD3LMC.jpg

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31 minutes ago, Stierlitz.Dango said:

With the similar principle, filling diesel in the cell wall structure actually worked like an ERA and successfully weakened a HEAT testing warhead which capable of penetrating 280mm to 160mm by only 20mm thick of fuel cell armor.

 

A geometric efficiency ratio of 6 for fuel?

Seems a bit high to me but maybe the chosen geometry allow that.

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41 minutes ago, Stierlitz.Dango said:

Fuel Cell composite armor is believable....

And talk about fuel cell armor,i've heard an interesting design. Few years ago Chinese enginner has built a special fuel cell composite armor which uses Oplot-M ‘s design as reference.

1Y0g7wH.png

With the similar principle, filling diesel in the cell wall structure actually worked like an ERA and successfully weakened a HEAT testing warhead which capable of penetrating 280mm to 160mm by only 20mm thick of fuel cell armor.

8QO0HpN.jpg

rLbchQG.png

TmD3LMC.jpg

 

Actually it is a well known idea used in "cells" armor developed by hydrodynamic institute of Siberian departament of academy of scince of USSR in 70s. http://btvt.info/5library/vot_yacheiki.htm

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3 hours ago, Stierlitz.Dango said:

Fuel Cell composite armor is believable....

And talk about fuel cell armor,i've heard an interesting design. Few years ago Chinese enginner has built a special fuel cell composite armor which uses Oplot-M ‘s design as reference.

1Y0g7wH.png

With the similar principle, filling diesel in the cell wall structure actually worked like an ERA and successfully weakened a HEAT testing warhead which capable of penetrating 280mm to 160mm by only 20mm thick of fuel cell armor.

8QO0HpN.jpg

rLbchQG.png

TmD3LMC.jpg

More about how this works can be found in this paper: https://www.researchgate.net/publication/281489377_Theoretical_Study_of_a_Diesel-Filled_Airtight_Structure_Unit_Subjected_to_Shaped_Charge_Jet_Impact

 

If you want the full paper, PM Me.

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OqGTyzJ.png

 

From the article "Antiarmor - what you don't know could kill you" by US Army Reserve Major Michael R. Jacobson. There are some errors in the data (M60A1 protection level, muzzle velocity of the M829A1 APFSDS, etc.), but it seems overall to be quite interesting.

 

On 19.3.2018 at 5:36 PM, Alzoc said:

 

A geometric efficiency ratio of 6 for fuel?

Seems a bit high to me but maybe the chosen geometry allow that.

 

Probably spaced in front of the reference plate. Normal NERA achieves an even higher "thickness efficiency" if you include the empty space...

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2 hours ago, SH_MM said:

OqGTyzJ.png

 

From the article "Antiarmor - what you don't know could kill you" by US Army Reserve Major Michael R. Jacobson. There are some errors in the data (M60A1 protection level, muzzle velocity of the M829A1 APFSDS, etc.), but it seems overall to be quite interesting.

 

 

Probably spaced in front of the reference plate. Normal NERA achieves an even higher "thickness efficiency" if you include the empty space...

 

 

But how valid is this chart ?  Do you think the values really correspond to the actual protection values ?

 

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On 15.3.2018 at 2:01 PM, SH_MM said:

The British had some odd ideas about main battle tanks, although they wanted their MBT-80 to be more advanced in some aspects than the Challenger 2 currently operated by the British army...

  1. The lack of an indendepent sight for the commander was disliked
  2. The laser rangefinder of the M1 Abrams was incompatible with the thermal imager (?)
  3. For some reason the British military thought it was a bad idea to integrate daysight and thermal imager into a unitary optic
  4. The M1's fire control system resulted in a low hit probability (confirmed by statemens from US and German sources regarding the comparative trials of XM1 & Leopard 2AV)
  5. The armor of the M1 Abrams could be penetrated at ranges of 4,000 m by the 125 mm gun according to British estimates
  6. Storing ammo below the turret ring is/was seen as better than having a separated ammunition compartment at the rear of the turret because some US test proved that it might not always work with 105 mm ammo and wasn't tested with 120 mm; also the blast door needs to be open for reloading (silly complaint)

 

K7E4Sox.jpg

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1 hour ago, SH_MM said:

 

K7E4Sox.jpg

 

I wonder if they were considered fails because the primer was hit (implying an ammunition detonation) or if the burning propellant was able to overwhelm the storage system.

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Hello guys, i need your wisdom and insight!

 

would you guys know the approximate LOS thickness of the Leclerc front hull "beak" ?

 

Leclerc_armor_sb2x.thumb.jpg.0dcf1857b21

Im looking for the LOS thickness of the special armor in front of the fuel cell.

 

Here is my preliminary estimate:

 

Leclerc_front_hull_7.jpg.42cc2c479b04ca8

 

 

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SH_MM, some of the protection level bullets are familiar, some less so. 

 

More specifically:

 

It's a very nice summary, so I'd love to see the sources I'm missing that provide the additional specificity. My search terms may have failed me and I may have missed the links b/c I'm new to the site...

 

P.S. Greetings

  • On 3/1/2018 at 7:54 AM, SH_MM said:
    •  
    •  
    • That leaves us with the following (is there any easy way to add tables?):
    • Tank type
    • T-72
    • Leopard 2K
    • Leopard 2AV
    • (X)M1 Abrams
    • MBT-80
    • Weight
    • 41 tonnes
    • up to 47.5 tonnes
    • 56.935 tonnes
    • 52.6 tonnes
    • (?)
    • KE threat
    • 105 mm "next-generation" AP(FS)DS from 500 m along ±30° from the centerline
      14.5 mm - 20 mm AP allround (?)
    • 105 mm APDS from 800 m along ±15° from the centerline (turret only),
      90 mm AP(DS) from 1,500 m along ±15° from the centerline (hull),
      20 mm AP from 100 m (upper portions of the hull sides) or from 500 m at 20° (lower portion)
      14.5 mm AP from 100 m (engine comparment)
    • 105 mm APFSDS with 38 mm core diameter (ammo for the smoothbore gun?) along ±30° from the centerline,
      7.62 mm AP at 30 m (engine vents),
      14.5 mm AP all-round (20 mm AP at crew compartment?)
    • 115 mm APFSDS from 800 - 1,200 m range,
      14.5 mm AP all-round (?)
    • 125 mm APFSDS from 1,000 m range,
      14.5 mm AP all-round
    • CE threat
    • 9M14 Malyutka (AT-3 Sagger) at ±30° from the centerline
    • None
    • MILAN warhead
    • 127 mm HEAT warhead (TOW-1?) at ±25° from the centerline,
      81 mm HEAT at 45° (crew compartment)
    • (?)
    • Artillery threat
    • (?)
    • 155 mm artillery fragments at 10 m
    • 155 mm artillery fragments at 10-15 m,
      155 mm artillery fragments at 25 m (vehicle rear),
      no protection required (cover above the tracks at the engine compartment)
    • 95% protection against 155 mm splinters at 15 m (crew compartment),
      57% protection elsewhere
    • 155 mm splinters at 10 m
Edited by Olds
increased specificity, grammar

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5 hours ago, Olds said:

 

SH_MM, some of these protection level bullets are familiar, some are not. Are these all definitely documented somewhere--some other thread with links or whatever--or is this a list from memory? (I don't mean that in a bad way :), but I'm curious just how definitive some of these items are).

 

P.S. Greetings

  •  

Welcome to SH Olds.

http://sturgeonshouse.ipbhost.com/topic/4-a-beginners-guide-to-posting-on-sh/

 

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here is some info dealing with the protection requirement of the Chieftain of the 1980s:

 

Chieftain_protection_medium

 

 

This also makes me believe that the turret "cheek" armor protection of the Challenger 1 is 500+ mm RHAe against subcalibre KE threats. The Armed Forces Journal estimate of 580 mm RHAe and the British CR1 engineer "rumor" of 620 mm RHAe seem indeed plausible.

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The following diagram seems to show some old "weldlines" on the hull of a Leclerc prototype concept. Given the dimensions of the hull, nothing much seems to have changed between this prototype concept and the Leclerc Serie 1 hull.  This would give the front hull a LOS thickness of 600-620 640 mm, which conveniently falls within the limits of the earlier diagram:

 

Leclerc_prototype_concept_drawings

 

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8 hours ago, Laviduce said:

engineer "rumor" of 620 mm RHAe seem indeed plausible.

CR2 have lower KE protection than M1A1HA which have 600mm vs KE, so CR1 can't have 620 or 550, and if take some numbers from some british reports about CR1, it's hull front for example have less protection than Shir2 with it's "325mm"

 

but again, all this numbers useless if you don't know which round was used, on which striking velocity etc...

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1 hour ago, Wiedzmin said:

CR2 have lower KE protection than M1A1HA which have 600mm vs KE, so CR1 can't have 620 or 550, and if take some numbers from some british reports about CR1, it's hull front for example have less protection than Shir2 with it's "325mm"

 

but again, all this numbers useless if you don't know which round was used, on which striking velocity etc...

I also read that the CR2 was expected to have a KE resistance lower than that of the M1A1 HA. I think this came from a British assessment document.   Yet there is a problem , the British were aware of the threats posed by the 125 mm guns. There is little reason to believe that the British were not successful of reaching a protection level of 500 mm RHAe in the 60 frontal arc. This would translate to about 580 mm RHAe from the front. The M1A1 HA KE protection in the frontal 60 degree arc was stated to be around 600 mm RHAe. This would translate to a KE resistance of up to 690 mm directly from the front.

 

What we know:

 

CR1 - Armed Forces Journal estimate: 580 mm RHAe

CR1 -  Engineer Rumor:  620 mm RHAe

 

Average between the sources: 600 mm RHAe

 

M1A1 HA - multiple sources - up to 690 mm RHAe

 

CR2 - British document projection - below M1A1 HA level

 

This would give us:     600 mm RHAe < CR2 KE resistance < 690 mm RHAe      -> reasonable middle ground for the CR2 turret cheek armor from the front 650 mm RHAe

 

This would satisfy the requirement of the CR2 offering marginally inferior KE resistance compared  to the M1A1 HA but marginally superior KE protection compared to the CR1. Now 50 mm is not much of an improvement but it could still be true. 

 

The jump in KE resistance from the M1 to the M1A1 was also around 50 mm if we follow the given sources.  The increase in CE resistance was more significant, from 700 mm RHAe all  the way up to 1000 mm RHAe for the frontal 60 degree protection arc.

 

The CR2 could have followed the same idea, where an increase in CE protection was emphasized over an increase in KE protection.

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4 hours ago, Collimatrix said:

I note that in 10 pages, the Abrams, Leo 2 and even Challenger have had their defenders, but nobody has gone to bat for the Ariete.

 

Aren't the info available on it extremely sparse?

(Plus I don't know if we have an Italian member on the forum^^)

 

Doesn't help that most of it's systems have been designed indigenously, though that make it interesting.

 

There's a rumor that the goal was to produce a tank which was just able to overmatch a T-72B  both in protection and firepower and not more, to keep it cheap.

I don't know if it's true.

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3 hours ago, Alzoc said:

 

Aren't the info available on it extremely sparse?

(Plus I don't know if we have an Italian member on the forum^^)

 

Doesn't help that most of it's systems have been designed indigenously, though that make it interesting.

 

There's a rumor that the goal was to produce a tank which was just able to overmatch a T-72B  both in protection and firepower and not more, to keep it cheap.

I don't know if it's true.

 

according to mysterious sources:

 

" ... In any case, the level of protection, in particular against APFSDS projectiles, remains the Achilles' heel of the vehicle, reaching 500 mm in the frontal arc of the turret (C1 Ariete), a thickness comparable to that of a Soviet T-72B of the 1980s  but lower than that of contemporaries M1 Abrams or Leopard 2. "

 

Yay !!!! :P

 

...wait a minute!!!! :o:what:

 

 source!!!!!!!!!!!!!!!!: https://web.archive.org/web/20070208043716/http://collinsj.tripod.com/protect.htm#13    :wacko::huh:

 

OM*G!  <_< 

 

The turret values might actually be correct but there is no way of practically veryifying it either way. Nooooooooooooooo!!!!

 

 

:shitpostdiarrhea:

 

 

 

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