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I'm pretty dubious about the line that the Challenger 2 is the best armored contemporary MBT.  First, how would anyone know?  If they know for sure, they're not talking.  Second, Abramses have had two armor package upgrades since chally 2 debuted (SEP and TUSK).  Third, the Leclerc is more geometrically efficient than any of the other NATO MBTs, since it has one less crewmember to defend, and is only slightly lighter.  Absent specific information about armor performance, wouldn't simply geometry tell you think that's the best armored one?

 

Well, if you include TUSK as armor kit for the Abrams, then you also have to include the different Theatre Entry Standards (TES) armor kits (three versions at least) of the Challenger 2. The base armor however was most likely not upgraded.

 

The Leclerc is not geometrically more efficient. It could have been, if it's armor layout wasn't designed so badly. The Leclerc trades a smaller frontal profile for a larger number of weakspots. It uses a bulge-type turret (no idea about the proper English term), because otherwise a low-profile turret would mean reduced gun depression (breech block hits the roof when firing). There is bulge/box on the Leclerc turret roof, which is about one feet tall and located in the centerline of the turret. It is connected to the interior of the tank, as it serves as space for the breech block to travel when the gun is depressed. With this bulge the diffence between the Leopard 2's and Leclerc's roof height is about 20 milimetres.

 

eIUyqAK.jpg

 

The problem with this bulge is, that it is essentially un-armored (maybe 40-50 mm steel armor); otherwise the Leclerc wouldn't save any weight. While the bulge is hidden from direct head-on attacks, it is exposed when the tank is attacked from an angle. Given that modern APFSDS usually do not riccochet at impact angles larger than 10-15° and most RPGs are able to fuze at such an angle, the Leclerc has a very weakly armored section that can be hit from half to two-thirds of the frontal arc and will always be penetrated.

 

6HbQSlr.jpg

 

The next issue is the result of the gunner's sight layout. While it is somewhat reminiscent of the Leopard 2's original gunner's sight placement for some people, it is actually designed differently. The Leopard 2's original sight layout has armor in front and behind the gunner's sight, the sight also doesn't extend to the bottom of the turret. On the Leclerc things are very different, the sight is placed in front of the armor and this reduces overall thickness. This problem has been reduced by installing another armor block in front of the guner's sight, but it doesn't cover the entire crew.

 

1412522094-leclerc-gun-shield.jpg

 

The biggest issue of the Leclerc is however the gun shield. It's tiny, only 30 mm thick! Compared to that the Leopard 2 had a 420 mm gun shield already in 1979. The French engineers went with having pretty much the largest gun mantlet of all contemporary tanks, but decided to add the thinnest gun shield for protection. They decided to instead go for a thicker armor (steel) block at the gun trunnions.

 

1412521883-8387110204-85a735351b-c.jpg

 

Still the protection of the gun mantlet seems to be sub-par compared to the Leopard 2 (420 mm armor block + 200-250 mm steel for the gun trunion mount on the original tank) and even upgraded Leopard 2 tanks. The Abrams has a comparable weak protected gun mantlet, but it has a much smaller surface. The Challenger 2 seems to have thicker armor at the gun, comparable to the Leopard 2.

 

Also, the Leclerc has longer (not thicker) turret side armor compared to the Leopard 2 and Challenger 2, because the armor needs to protect the autoloader. On the other tanks, the thick armor at the end of the crew compartment and only thinner, spaced armor/storage boxes protect the rest of the turret. So I'd say:

  • Challenger 2: a few weakspots, but no armor upgrades to the main armor
  • Leclerc: a lot of weakspots, but lower weight and a smaller profile when approached directly from the turret front
  • M1 Abrams: upgraded armor with less weakspots, but less efficient design (large turret profile and armor covers whole turret sides)

So if you look for a tank that is well protected, has upgraded armor and uses the armor efficiently, the current Leopard 2 should be called best protected tank.

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Interesting.

That said, the commander and gunner both sit quite low in the turret of the Leclerc.  How much danger is the gunner in if the weak zone behind the gunner's sight gets penetrated?  Ditto the hump for the gun; if that gets penetrated from the side, crew injury seems unlikely.

 

Also, I'm not convinced that the protected volume inside the turret of the Abrams is any wider than the protected volume inside the turret of the Leo 2.  Look at where the crew hatches are located:

 

abrams1.jpg

 

The Abrams has a wider turret than the Leo 2 (and a very slightly wider turret ring), but most of the additional width of the turret appears to come from the enormously thick turret side armor.  The protected internal volume is greater because the ammunition rack is bigger, but the ammunition rack is isolated.

 

I Agree generally about gun mantlets.  The Challenger 1 design seems to have gotten that right.  I can't think of much else it got right (I guess the suspension is good?).  Mantlet design of Challenger 2 seems like a step backwards.

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That said, the commander and gunner both sit quite low in the turret of the Leclerc.  How much danger is the gunner in if the weak zone behind the gunner's sight gets penetrated?  Ditto the hump for the gun; if that gets penetrated from the side, crew injury seems unlikely.

The spall cone created by shaped charges can be larger than 90°, in such a case there is quite some danger of the crew being injured. Fragments of the projectile/shaped charge jet might also damage the internals of the tank, rendering it useless. I wouldn't assume that hitting this place or the gunner's sight won't cause harm to the crew.

 

Also, I'm not convinced that the protected volume inside the turret of the Abrams is any wider than the protected volume inside the turret of the Leo 2. Look at where the crew hatches are located:

abrams1.jpg

The Abrams has a wider turret than the Leo 2 (and a very slightly wider turret ring), but most of the additional width of the turret appears to come from the enormously thick turret side armor. The protected internal volume is greater because the ammunition rack is bigger, but the ammunition rack is isolated.

 

Based on photographs, the side armor of the M1 Abrams is not thicker than the side armor of the Leopard 2 or the Challenger 2. The M1 Abrams just has a very large commander's cupola, which creates the illusion of the hatches being located closer. The Abrams turret has about 10% more frontal surface and has about 40% more side armor volume (at the ammo racks), so I'd expect it to have less frontal armor at the same weight.

 

I Agree generally about gun mantlets. The Challenger 1 design seems to have gotten that right. I can't think of much else it got right (I guess the suspension is good?). Mantlet design of Challenger 2 seems like a step backwards.

The problem of the mantlet-less design of Challenger 1 and Chieftain, is that it had a negative impact on too many other aspects. For example replacing the gun barrel took about 24 hours, while the same task can be done within half an hour with proper equipment on the Abrams and Leopard 2 tank.

 

The lack of a proper gun mantlet also meant lower protection; while the size of the weakspot is smaller, the armor still gets thinner at the gun mount.

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The spall cone created by shaped charges can be larger than 90°, in such a case there is quite some danger of the crew being injured. Fragments of the projectile/shaped charge jet might also damage the internals of the tank, rendering it useless. I wouldn't assume that hitting this place or the gunner's sight won't cause harm to the crew.

 

 

Based on photographs, the side armor of the M1 Abrams is not thicker than the side armor of the Leopard 2 or the Challenger 2. The M1 Abrams just has a very large commander's cupola, which creates the illusion of the hatches being located closer. The Abrams turret has about 10% more frontal surface and has about 40% more side armor volume (at the ammo racks), so I'd expect it to have less frontal armor at the same weight.

 

The problem of the mantlet-less design of Challenger 1 and Chieftain, is that it had a negative impact on too many other aspects. For example replacing the gun barrel took about 24 hours, while the same task can be done within half an hour with proper equipment on the Abrams and Leopard 2 tank.

 

The lack of a proper gun mantlet also meant lower protection; while the size of the weakspot is smaller, the armor still gets thinner at the gun mount.

Leopard 2A4 or Leopard 2A5+?

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The problem of the mantlet-less design of Challenger 1 and Chieftain, is that it had a negative impact on too many other aspects. For example replacing the gun barrel took about 24 hours, while the same task can be done within half an hour with proper equipment on the Abrams and Leopard 2 tank.

 

The lack of a proper gun mantlet also meant lower protection; while the size of the weakspot is smaller, the armor still gets thinner at the gun mount.

 

That's just ham-handed misdesigning then.

 

The gun trunnions jut forward; put more armor over them!

 

The gun can't be removed from the front.  Put an access panel on top of the turret (like IS-3 had).

 

 

Edit:

 

Per Froggy on the SB forums, Leclerc's mantlet has composite fill.

 

If this is the same Froggy as on TN, then he is a Leclerc crewman and does know his stuff.

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When comparing the Leopard 2 and Abrams protected volume, remember that the Abrams is shorter and that the hatches on an Abrams are closer together (even when accounting for the large commanders cupola on the M1A2).

 

 

UxfIkOI.jpg

 

GwDeQ69.jpg

 

c7Mzb0s.jpg

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When comparing the Leopard 2 and Abrams protected volume, remember that the Abrams is shorter and that the hatches on an Abrams are closer together (even when accounting for the large commanders cupola on the M1A2).

 

 

UxfIkOI.jpg

 

GwDeQ69.jpg

 

c7Mzb0s.jpg

Welcome to SH good sir. :)

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Leopard 2A4 or Leopard 2A5+?

 

In reference to what statement?

 

Per Froggy on the SB forums, Leclerc's mantlet has composite fill.

 

If this is the same Froggy as on TN, then he is a Leclerc crewman and does know his stuff.

 

How thick is this composite armor? Is this only the 30 mm gun shield or also the armor at the gun mount? How much area does it cover? And how did Froggy "discover" this?

 

When comparing the Leopard 2 and Abrams protected volume, remember that the Abrams is shorter and that the hatches on an Abrams are closer together (even when accounting for the large commanders cupola on the M1A2).

 

The Abrams is not shorter. It has a longer hull (7.92 metres vs 7.672 metres) and a longer turret (at the turret centerline, the Abrams' turret has a length of 4.77 metres, where as the Leopard 2's turret has a length of only 3.99 metres). The only difference is the location of the unarmored external storage boxes, which in case of the Leopard 2 are all located behind the turret, increasing the visible turret length without affecting the internal volume. On the Abrams, external storage boxes are not only located at the turret rear, but also at the rear side section. I think it is obvious why I am not including the storage boxes:

 

KuJNABd.png

 

As for the hatches, them being closer together means nothing. If you have a sheet of paper and draw to circles with a distance of X, putting two larger circles onto another sheet of paper at the same position will reduce the distance to less than X.

 

The commander's cupola has a diameter of 31.75 inches (806 mm; slightly more if you include it's "turret ring"), which is a lot more than the 500-550 mm diameter of normal hatches as found on the Leopard 2 and for the M1 Abrams' loader.

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They all have the same Diehl double-pin, rubber-bushed tracks.  Most of them have the same gun.  Most of them have, or can be ordered with the same power pack containing the same MTU liquid-cooled diesel with the same Renk transmission.

 

Ariete_tank_of_the_Italian_Army.jpg

 

640px-Challenger_2_Main_Battle_Tank_patr

xEu3ckK.jpg

 

8KZsQxT.jpg

 

GjUaMnr.jpg

 

qhP9iqt.jpg

 

iKVz5Iz.jpg

And let's face it, they even look the same.

 

It is time to argue minutiae of enclosed volume dimensions, probable contents of classified armor packages, and fire control systems to determine WHICH WESTERN MBT IS SUPREME!

 

 

(To any who are confused, I moved a bunch of posts into this thread to prevent another from being derailed.  This post is supposed to be the OP, but it shows SH_MM is the thread author because IPBoard always orders posts by date.)

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How thick is this composite armor? Is this only the 30 mm gun shield or also the armor at the gun mount? How much area does it cover? And how did Froggy "discover" this?

 

 

If you read on in that thread, it's pretty clear that it's the same Froggy as on Tanknet, and that he's served on the AMX-56.

 

Not that a composite block that thick would do much, given same TE values for most array, but I could see the mantlet armor taking it from something that gets penetrated by 40mm autocannon fire to something that gets penetrated by 90mm HEAT.

That said, the mantlet design is baffling for something that's clearly supposed to fight hull down (the hump on the turret roof).

Supposedly the weird gunner's sight design in the Leclerc is where it is so that it can be directly connected to the right gun trunnion, to ensure accurate and repeatable zero with the main gun:

 

BJDZr7s.jpg

 

I wonder if there was similar rationale with the placement of the sight on early Leo 2s and on the Arjun.

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In reference to what statement?

 

You said it took about half an hour to change the gun barrel on the Leopard 2 with proper equipment.

 

When you said Leopard 2, did you refer to the Leopard 2A4 or to the Leopard 2A5 and later variants? 

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The Abrams is not shorter.

Except it is, I am not talking about length. The hull of an Abrams at the turret ring is the same height as the hull of a T-72 at the turret ring, while the hull of a Leopard 2 at the turret ring is significantly higher than the hull of a T-72 at the turret ring.

Furthermore the turrets do not have the same vertical thickness at the front where the armor cavity volume (and weight) is.

As for the hatches, them being closer together means nothing.

The inner walls of the side armor come up to the hatches (at least on the Abrams), if the combination of hatch/cupola width and distance between hatches is smaller on one tank then there is less internal width being armored.

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Except it is, I am not talking about length. The hull of an Abrams at the turret ring is the same height as the hull of a T-72 at the turret ring, while the hull of a Leopard 2 at the turret ring is significantly higher than the hull of a T-72 at the turret ring.

The upper photographs are a bit misleading. The tanks were photographed from different distances; you can see that by comparing the size of the measuring pole: each square is about 9-10 pixels high on the Leopard 2 photo and only 7 pixels on the T-72 photograph. Correcting this shows that the Leopard 2's hull is about 160 mm higher; however the Leopard 2 has a ground-clearance of 550 mm (reduces to 500-520 mm at the engine compartment), while the T-72 has a ground-clearance of only 490 mm. As such, the hull height difference at the turret ring might be only 100 mm.

 

German author Rolf Hilmes wrote a chapter in one of books solely to compare the T-72(A) to the Leopard 2. This is based on the official evaluation of ex-GDR tanks analyzed by the Bundeswehr after the reunification of Germany. According to him, the difference in hull height is 188 mm, but he didn't write at which exact position (other than comparing the total height).

 

Comparing other photographs of the T-72M1 and M1 Abrams, there seems to be a similar-sized hull height different, if we take into account ground-clearance (Abrams and T-72 have essentially same ground-clearance).

 

VoTpZ8G.jpg

 

Note that the ARAT reactive armor covers only the side skirts, the tank hull actually extends over these skirts though. In so far I would be careful with claiming that the hull height of the Leopard 2 is much greater and the tank thus has a greater internal volume. Should I measure scale drawings or photograhs to come up with a mililmetre value?

 

Furthermore the turrets do not have the same vertical thickness at the front where the armor cavity volume (and weight) is.

Not the exact same, but very close. Given that more of the Leopard 2's frontal turret profile is covered by the sloped roof armor, the Abrams might actually have more vertical thickness at the front.

 

The inner walls of the side armor come up to the hatches (at least on the Abrams), if the combination of hatch/cupola width and distance between hatches is smaller on one tank then there is less internal width being armored.

It is however not the case. The scale measurements have some margin of error, but the roof section excluding the armor is at most 20 mm larger on the Leopard 2. If you take into account that the M1's turret is much longer (see previous posts) and it's width increases downwards (from ~2.5 to ~3.3 metres), it will have a quite larger internal volume.

You said it took about half an hour to change the gun barrel on the Leopard 2 with proper equipment.

When you said Leopard 2, did you refer to the Leopard 2A4 or to the Leopard 2A5 and later variants?

This was the case of the old Leopard 2 (2A4).

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I never thought of the Leo 2 as a particularly big tank. It's narrower than the Abrams, if perhaps a tad taller.

According to General Dynamics, a M1A2 is 3.66 meters wide and 2.38 meters tall with a ground clearance of .48 meters.

According to KMW, a Leopard 2A6 is 3.77 meters wide and 2.64 meters tall. They do not state a ground clearance but according to MM it is .55 meters.

This means a Leopard 2A6 is .11 meters wider and .19 meters taller (hull bottom to turret roof).

 

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Leopard 2A6 is 2.64 metres tall with the additional bomblet protection at the turret roof, as operated by Greece and Spain; the height of the roof of a Leopard 2 without bomblet protection is 2.48 metres as you can read in Spielberger's books on the Leopard 2.

The width of the Leopard 2 is greater because of it's thicker heavy ballistic skirts at the frontal hull; on the Leopard 2 to 2A4, the width was 3.70 metres. On the late batches of the Leopard 2A4 and follow up models (2A5, 2A6, 2A7), thicker heavy ballistic skirts increase the total width of the tank to 3.76 metres. Without any skirts, the Leopard 2's width is only 3.42 metres (Spielberger). Given

 

The Leopard 2 has much thicker, but shorter heavy ballistic skirts. On the M1 Abrams, the frontal skirt elements have a thickness of supposedly 70 mm (claim made by a US tank crew member), while on the Leopard 2 the thickness is 110 mm (earlier versions) or 150 mm (later versions; skirts are mounted a bit closer to the tracks). This is why the Leopard 2's hull is actually not as wide as the hull of an Abrams tank.

 

nKwZFoG.jpg?1

 

pAhMHRz.jpg?1

 

Excluding skirts and optional roof armor, the Leopard 2 is 30-40 mm taller (ground clearance 550 mm vs 482 mm), but the Abrams is 100 mm wider. That's why calling the Leopard 2 a giant compared to the Abrams is not justified.

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Does anyone have ground clearance figures for the T-72?  I had always heard that it's about two inches less than for Western MBTs.

I'm also curious where the ground clearance is measured from, because the bottom of the T-72's hull is an irregular shape:

 

OgGpxhJ.jpg

 

Also curious if anyone has figures showing the approximate thickness of the armor in the front hull of the Leo 2.  Frontal hull vulnerability, at first glance, looks like one area where the Abrams is greatly superior to the Leo 2.  The left side of the Leo 2 hull is filled up with non-compartmentalized ammo and the right side of the Leo 2 hull is filled up with driver.  On the Abrams the driver is centerline, and the right and left are filled with fuel tanks.

 

4XflE0c.jpg

So unless the lower front plate and glacis of the Leo 2 are both way thicker than the hull armor on the Abrams (not entirely impossible; Abrams' glacis is rather thin), the hull is quite a bit more vulnerable from attack straight ahead.

Attack against the front of the hull from oblique angles will favor the Abrams as well, especially against CE threats.  The driver is centerline, and thus protected by the fuel tanks as well as the hull side armor.

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I always thought it was an odd decision to put the ammo at the front. 

What else to put there? It makes more sense to put fuel tanks in the rear or on the sponsons. Radios and bow gunners were deleted, and the engines in general are too big. So why not increase the tanks ammunition capacity and reduce the size of the rest of the tank?

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What else to put there? It makes more sense to put fuel tanks in the rear or on the sponsons. Radios and bow gunners were deleted, and the engines in general are too big. So why not increase the tanks ammunition capacity and reduce the size of the rest of the tank?

 

Erm... I like fuel tanks up front. That way, if you get hit, the fuel acts as a dampener.

Ammo just explodes.

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Erm... I like fuel tanks up front. That way, if you get hit, the fuel acts as a dampener.

Ammo just explodes.

I am fully aware that you can put fuel tanks there, my point was that it's a big empty space that is excellent for ammunition storage. Of course, putting fuel tanks there makes more sense in terms of protection, but not when it comes to space efficiency.

 

But pretty much, a tank designer has 3 options:

Put fuel there to improve protection.

Put ammunition there to improve ammunition load without increasing the size of the tank.

Put an engine there to allow a rear hatch or to make it more modular. 

 

4 if you use a unmanned turret:

Put the rest of the crew members there. 

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      Now, we head back to that chart:


       
      On the left side of the graph, we put our cursor on the line that corresponds to approximately 3,150 ft/s velocity, and follow it over until it hits the curved line that corresponds with the angle of plate we care about - arbitrarily, let's pick 20 degrees. Then, we follow that point straight down until it hits the x-axis:


       
      Therefore, we estimate that at 2,000 yards, my 85mm has just over 10 inches of RHA penetration - not bad at all for a lowly APCR round!
    • By Walter_Sobchak
      Since we don't have a thread for British and Commonwealth tanks of WWII, I thought I would start one.  
       
      Check out this manufacturers instructional video on the Crusader.
       
       
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