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Britons are in trouble


Mighty_Zuk

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9 hours ago, 2805662 said:


Got a link or similar of the Greek article?

It was on the dead district blog spot back in 2017:
 
The Chronology of the New Army Program of the Greek Army looks as follows:
  • 1996: Launched and completed in the Greek Army "Research of the need for a new technology of modern technology"
  • December 1996: Approval of the need for a new tank by the High Military Council.
  • January 1998: Establishment of technical-tactical requirements of the modern tank of the Greek Army.
  • February 26, 1998: Approval of technical-tactical requirements of the new tank by the High Military Council.
  • August 3, 1998: European Ariete, British Challenger-2E, French Leclerc, German Leopard-2A5S, Jewish Merkava Mk-III, American M1A2 Abrams, Russian T-80U and Ukrainian T-84) Two out of eight, Italian and Jews have refused to participate in the competition due to reasons.
  • From 14 October to 18 December 1998: Six tanks of six tanks were carried out at the Lyothoro firing ground in Greece.
  • February 15, 1999: The Commission headed the General Staff of the Defense Ministry of Greece.
  • October 5, 1999: Presentation of "RFI: Request for Information" to purchase 24 evacuation vehicles, 12 carpets, 12 training corps, 12 training towers, 246 pieces of new technology and other training facilities.
  • November 15, 1999: Six participating companies have submitted a technological proposal and economic discount in response to the Greek RFI.
  • January 4, 2001: The General Department of the Armed Forces of the Greek Army requested BAOF (Best and Final Offer).
  • 19 January 2001: Six companies presented BAOF.
  • End of January 2001: The Greek side demanded producers the most modern selling modes, their prices and final economic indicators. At the third turnover, the total cost of the program was significantly reduced.
  • March 1, 2002: The Greek side decided to purchase 170 pieces of Leo-2.
  • March 1, 2003: Greece and KMW signed a contract to buy tanks.
  • March 30, 2008: Leo-2HEL officially adopted the army of the country's army at the XXV Tank Brigade in Xanthi Petrocoros, Greece.
 
For the launch of the program (in 1996), the 1735 acting tanks were included in the Greek Army. This was the maximum allowed by the CEF. The entire tank park structure was as follows:
 
  • M-60A3 - 312
  • M-60A1 - 357
  • M-48A5MOLF - 395
  • M-48A3MOLF - 400
  • M-48A5 - 304
  • M-48A3 - 11
  • Leo-1GR - 105
  • Leo-1V - 170
  • Leo-1A5 - 77

 

The Turkish army had the following tank park:
 
  • M-60A3 - 658
  • M-60A1 - 164
  • M-48A5T2 - 760
  • M-48A5T1 (lightly improved M-48A5) - 1560
  • M-48A5T5 - 183
  • Leo-1T1 (ie improved Leo-1A3, which was the Greek Leo-1GR counter strike) - 227
  • Leo-1T2 (ie Leo-1A1A4) - 170

 

PS Totally Turkey had 2795 tanks in the CEF Agreement Zone (ATTU Zone). Outside of this zone, or in any of the tanks, in South-East Turkey could have.
 
The Greek procurement tank cost 1 959 824 581 (almost two billion euros). From this the producer was given 1 659 000 000 euros for the cost of arrangement of equipment and manufacturing lines, and the rest went to various taxes and financial operations. The Greek side purchased 183 pieces of Leo-2A4 (50,000 euros) in addition to 170 Leo-2A6, and received 150 pieces of Leo-1A5.
What happened in the fall of 1998 at the Lyothoro firing range
- The six best tanks in the world first compete with each other. In addition, the Eastern and Western schools of tank construction have been challenged for the first time.
The purpose of the exams was to examine the technical data in real-time conditions. Which usually does not match the manufacturer's advertisements often. It should measure the data such as acceleration, maximum speed, stroke supplies, stabilization quality and more.
Storage reserve - accessed to a large distance, from Lyothoro to Poliskaustro on the road and covered a mixed passage (asvalust and ground). All tanks were equipped with Greek fuel simultaneously, put in the column and paved the way. The aim was to move the tanks up to the fuel. As a result of which the tanks came up, their assessment took place. After the fuel generation, the M1A2 has been on the first track, it is clear that its gas turbine burns a lot of fuel compared to classical diesel. The distance that the tank has passed or is relatively small compared to the others, but the manufacturer has more than ever been declared. The best indicator was the French Leclerc, who was "not going to stop". This is the smallest weight (10 tons light compared to other western tanks), and by the time of the mid-range 1500 hp diesel engine MTU MB-883, the engine is low-voltage compared to the MTU MB-873 installed on the Leo-2. The French tank's similar engine was also on the British Challenger-2E, but its heavier weight reduction in stock.
 
The GIAT team is preparing to enter the tanks Leclerc
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60% surprise was a terrible test for all participants. The tanks should be safe on the elevator and come down, and in addition to stop in the middle of the road, engage the engine, then lie down and drive back or forward without hitting. The resistance was ideally passed by Leclerc, with good results showing M1A2 and Leo-2A5S, while the remaining three participants had problems with overcoming resistance.
 
Tank Leclerc and T-80U 60% surfacing point. Observe the Russian tanks Zakrdeni most part of the surface does not touch the concrete
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Challenger-2E and T-80U at the moment of crossing the trench
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Challenger-2E has lost almost all rubber pedals at the moment of the vertical resistance
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Absolute test was a day and night shoot. The uneven ground of the lycourt polygon was a great problem for the stabilizer. The tanks have to move more speed than the speed allowed at motion relief. In this test, the eastern tanks showed a marked lag. The best German West was the Leo-2A5S, which showed the ideal result in the shooting, which is the perfect work of stabilizer and fire management system. Leopard was very close to M1A2, third and fourth places respectively, according to Leclerc and Challenger-2E.
 
M1A2 M-865 Practical Shot Pallet for M1A2 and the moment of booting
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Leclerc's subalbital shells and the moment of shelling load in automatic charger
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Inspection of the carriage was the following: - The representatives warned that the tanks were in perfect condition and prepared for the test. On the horizontal aspiration path, the tanks were to be stopped only after braking with the help of brake. These extreme braking machines should be replicated ten times. The Ukrainian and Russian tanks did not complete the test, the first, second and third places from the western tanks were respectively Leclerc, Leo-2A5S and M1A2.
 
 
Final assessment of tanks
 
The tanks participating in the competition were as follows:
Compared with others, Leopard-2A5S was the best protector and was the only one to think that the manufacturer was serious about protecting the upper side of the tower. Excellent results in firing tests showed that it was quite reliable and convenient and ergonomic for crew.
M1A2 Abrams was the second best of armor. The Americans offered the Greeks the tank without the "Depleted Uranium" armor (DU reservation is still prohibited). The tank was superb enough and was a special ergonomic for the crew. The car was reliable and there was only one major disadvantage on the tests - it was a gas turbine engine that flattened the fuel.
Leclerc, which was a few years earlier by the French, differed from the variant offered for the United Arab Emirates, dual impression: the ideal building and the power machine (ie German firms, RENK and MTU, the last generation diesel engine and speed gear, Called Europack), an excellent hydro-pneumatic suspension and weight of participants The best ratio of A-power. All of this made it particularly fast and flexible, and with all of this, the fuel was low. In terms of armor, compared to the previous two western tanks, Leo-2A5S and M1A2 have always been distinguished in this regard, although its protection was probably too high. The tower, with a fully automated charger, offered a lot of innovative innovation to the customers, but in practice the automatic expectation did not justify the expectation and was constantly crippled and spoiled. On the other hand, the tank was not distinguished by the creativity of the crew (mainly due to the lack of existing space), for the same reason was the use of armaments, for example, pulverized machine guns. In the precision of the hand, well, but not the best.
Challenger-2E was one of the disadvantages. Despite the fact that the version presented in the competition was equipped with a similar type of Europack-type machine with the French tanks, it was often spoiled when switching to high speeds, which was the fault of the passing of the motorway on the motorway. The 1200-horsepower engine at Challenger-2 was replaced with a 1500 horsepower engine and did not adapt to the kinetic scheme and adjusted to the engine that caused frequent outflow of the carriageway. It was also a negative surprise with its annexed armor. The car was distinguished by a relatively weak armor compared to Leo-2A5S and M1A2, even with 10 tons of light Leclerc, almost never behind British tank protection.
The car was not very precise, it was the only one that was equipped with a 120 millimeter angle and used three shots (shells, sparkle and insulating capsules), while Ukrainians and Russians used both the shells and the rifles, and the British Doing this with automatic charging). However, the car had a positive side: he served in the army with long military experience and was the only one who had a toilet in the tower and traditional British tea makers.
The Russian T-80U was the classical representative of the Soviet tank construction. Its main problem was the semiconductor speed of the prototype at the moment, which was often out of order. The machine showed the lowest results in accuracy, as well as the crew's ergonomics. In addition, the two systems, which the manufacturer claims, compared with Western counterparts, the electric-optical flaw system and a 6-kilometer-long laser-guided tank missile in practice failed to demonstrate and did not show any possible results.
The Ukrainian T-84 was characterized by the Russian tank as a whole, but with another important minus, it was a two-ton diesel engine that was literally burned with oil and mechanical speed booths, and unlike the steering wheel of the Russian car. That's why the Greeks were saying jokingly "I need three hands for his control" (to turn the driver-mechanic into a curve, let alone the third hand). It is also worth mentioning that the car crew suffered the crew - the Greek crew was replaced by Ukrainian crew due to fatigue in checking stock.
In January 1999, the General Staff of the Greek Army presented the results of the competition, according to points according to the following scores:
  1. Leopard-2A5S - 78.3
  2. M1A2 Abrams - 72.95
  3. Leclerc - 71,92
  4. Challenger-2E - 69,89
  5. Т-80У - 59,2
  6. Т-84 - 56,3
The Challenger-2E tender was a bad surprise
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German Leopard-2A5S and Ukrainian T-84 ( 478ДУ2) on the lorigore tank firing range
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Lyothoro polygon, firing test results - Target M-48
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Armored shells on the M-48 tower
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The German sub-division DM-33, which is supported by the M-48 block
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On the lower two photographs of the Challenger-2E knotted cannon on the M-48's tower
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Again the M-48's tower and this time through the hamstring - American 120 mm sub-KW-KE-W
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M-48's tower. M1A12 Type M830A1 HEAT-MP-T Cumulative Sheet
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Run from Challenger-2E, the result of the HESH-type shell on the M-48 tower. But it did not break up, but inside the steel stainless steel "alloy" tanks, the crew had very little chances of survival (although this is the principle of HESH)
20170514_190718%2B-%2BCopy.jpg
 
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14 minutes ago, Laviduce said:

It was the aim of the British to improve the ballistic protection of the hull (glacis) "to a minimum of 500 mm" RHAe KE on a future "Challenger II and III" :

and there is british reports with "can we really do that?" so...

 

14 minutes ago, Laviduce said:

second only to the Strv 122

considering that there was also a scandal with Greek penetrated turret with israeli APFSDS, all those numbers pretty much useless 

 

14 minutes ago, Laviduce said:

"similar or never far behind"

it also could mean that both tanks have very low protection for example 

 

  

4 minutes ago, Laviduce said:

he upper side of the tower

and this is BS for example, no any advantage over T-80U/UD at the moment 

 

 

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41 minutes ago, Wiedzmin said:

and there is british reports with "can we really do that?" so...

 

considering that there was also a scandal with Greek penetrated turret with israeli APFSDS, all those numbers pretty much useless 

 

it also could mean that both tanks have very low protection for example 

 

  

and this is BS for example, no any advantage over T-80U/UD at the moment 

 

 

 

1) Maybe, maybe not

 

2) Weak spots do exist

 

3) Compared to other contenders, yes they were lagging behind a bit in terms of protection.

 

4) KE Protection wise overall, I would give the advantage to the T-80U/UD, particularly for the hull.

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12 hours ago, 2805662 said:

Got a link or similar of the Greek article?

 

It is an article published in the 372 issue of the Greek magazine Ptisi & Diastima ("Aviation and Space"), which despite its name covers also military technology and news in the land and naval sectors. It was published in May 2017.

 

I don't speak Greek, so I used the summary of Scout-TheDeadDistrict.blogspot.com (now defunct) as mentioned by Laviduce. I did however bother to fact check it as good as possible - for someone who doesn't speak Greek and found several references on the Ptisi & Diastima website (including the table of contents of the 327th issue of Ptisi & Diastima), an teaser article for the Leopard 2 HEL program coverage. When I originally checked Ptisi & Diastima, their website was still different and I found several (low quality) preview pages from the relevant article ("Η αλήθεια για το πρόγραμμα Leopard 2HEL· μια 20ετής αναζήτηση…") - unfortunately I cannot find them at the moment.

 

The original article is 26 pages long and contains (based on the preview images) quite a bit of additional info (lots of texts, but also tables and photos) that didn't make it into The Dead District's blog article.

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18 hours ago, Korvette said:

I don't see your point that the occupied volume of the hull array makes it less likely to be similar/identical to the turret?

 

Well, it depends on the exact armor layout. The problem is that the different slope will affect the effective protection provided by most materials (sloped steel being weaker against APFSDS rounds when sloped, unless sloped very high; NERA being less effective perpendicular to the threat, while ceramics are better in exactly the same situation).

 

If one does not account for these factors, the volume will be used less effectively. In case of the Leopard 2 (at least the Leopard 2AV) and the M1 Abrams, the shape of the hull armor cavities do not correspond to the actual shape/sloping of the armor arry. In case of British tanks, the shape of the armor cavities is less suited for such solution, hence the difference between the shape of turret and hull might be more relevant.

 

18 hours ago, Korvette said:

You can compare hull backplate to turret backplate and see that their thicknesses are very similar.

 

That is quite possible, though IMO the picture quality is too poor to make an accurate judgement.

 

18 hours ago, Korvette said:

I'd also like to see a source on why 'thin plates' are used for DU, the context is important.

 

British research on DU armor suggests that thin plates used in a NERA-like configuration are prefered, at least such an array (using very thin DU plates and poly-carbonate inter-layers) was revealed in a British publication:

KBNcRQI.jpg

Note that this armor is optimized for KE and each sandwhich plate is less than two inches thick. Both DU plates amount to less than half of the multi-layered plates thickness.

 

The US Abrams also apparently featured thin DU plates, at least in case of the M1A1 HA and M1A2. There is a 1995 report covering the SMC (Specific Manufacturing Capabilites) located at Idaho National Engineering Laborary, i.e. a facility run by Lockheed-Martin and the US Department of Energy specifically to manufacture DU elements for the M1A1 HA and M1A2 tanks. The reports speciifcally mentions that the shears (shears have to be used to prevent DU dust potentially contaminating the worker's lungs) are rated for DU plate thicknesses of 0.625 and 0.375 inches. This would suggest that at least some parts of the DU armor arrays of the M1A1 HA and M1A2 use DU plates with a thickness as low as 9.525 milimeters.

 

sxW7Hyb.png

 

18 hours ago, Korvette said:

The plate we see on the CR2's turret and hulls are backplates, something that must absorb the last amount of energy and force imparted upon it or in general, keeping the array in front unable to be compromised by resonating forces, and having a thin plate wouldn't bode well to withstand the possible threat against it, plus the possibility that these could be the only set of RHA plates within the array apart from the front plates encasing the entire tank, it wouldn't add up to be very heavy.

 

They are backplates, which is why it is extremely unlikely that they are made out of DU. DU is way to heavy.

 

How thick do you think is the backplate? To me it seems to be in the area of 40 to 50 mm (not accounting for slope).

Spoiler

nTOYbh0.jpg

L8PO0h7.jpg

 

The problem is that given the slope of the hull, you look at as much weight as a 188 to 235 mm thick steel plate (assuming a DU staballoy with a density of 18.5 kg/cm³). 188 mm thick steel weighs ca. 1,500 kilograms per m², a 235 mm steel plates weighs ca. 1,880 kilograms per m² . Given the size of the area covered by the backplate, that would already be more weight for the backplate than the Challenger 1 had for total Burlington armor on the hull front. Basically there would be no weight left for anything else (such as NERA layers required to reach the desired 800 mm protection against shaped charges). Without additional layers, the DU plate with additional steel front and back plates also would fail to reach the desired level of protection.

 

So either the backplate is not made of DU or there has been a massive, currently unexplained weight reduction in hull components and/or the existing steel armor.

 

The problem also exists for the turret. Turret armor slope is not as extreme, but the backplates are also fitted to the turret sides. Basically more than half of the turret armor's weight would be related to the backplates.

 

18 hours ago, Korvette said:

Other materials could have been used as the backplate but the specific mounting procedure on how it its attached to the hull and turret to me resemble other examples of DU being mounted as a plate. 

 

Other materials have to be used, as DU is simply to heavy.

Which other examples of DU being mounted as a plate for armor applications do you know?

 

 

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6 hours ago, Laviduce said:

A new non-DU armor package seems to have been used that seem to have improved protection significantly. Using "new geometries" it seems possible that this armor package could have been similar in performance to the 3rd Gen HAP, meaning that it could have been used on later US Abrams tanks.

 

This is unfortunately way to vague to make any reasonable assumptions. We don't know how much worse the armor in the Swedish trials was compared to the contemporary DU armor (or if it really was worse than the original HAP). If it was worse, we do not know if it was the protection against KE rounds that was inferior or if it was the protection against shaped charges. We also don't know if the distribution of armor wasn't changed for the Swedish trials, i.e. the lack of DU being compensated by shifting more weight from other armor arrays to the turret front.

 

One thing to keep in mind is the fact that the M1A2 failed to reach its original protection requirement, as the US Army insisted on keeping the tank's weight within a reasonable limit. GAO claimed that the reference threats were not ambitious enough (underestimating the Soviet's capabilities).

 

6 hours ago, Laviduce said:

I suspected this as well that CR2 has the same hull protection as the CR1, but I was not sure. According to this chart, which is in the Chasillan tank encyclopedia book supposedly, CR2E had the "weakest" hull protection out of all contenders:

 

Weakest hull protection can mean anything - for example it could be solely related to the lack of armored side skirts. Likewise it could refer to the size of the armor cavity being weaker or the weakspots (driver's hatch causing "big hole" in the armor array) being larger. It also could be a reference to overall weaker armor...

 

The whole table is odd. The claimed travel distances of the M1A2 and Leopard 2 are lower than found in other sources. Most of the "disadvantages" are randomly picked and apply to more or in some cases even to all tanks - such as the lack of mine protection, the lack of isolated hull ammo storage (that also applies to Leclerc and CR2), the lack of roof armor...

In another publication Marc Chasillan claimed that the AMX-30's protection levels were used as stand-in for the Leclerc's, which we know is incorrect, given that the protection of Leclerc and Challenger 2 was considered similar.

 

6 hours ago, Laviduce said:

Leclerc UAE/ S1/S2 front hull/glacis KE protection: ~500-540 mm RHAe

Challenger 2E front hull/glacis KE protection: ~500 mm RHAe  <- could also be 275-300 mm RHAe (CR1).

Strv 122 front hull/glacis KE protection: ~650-750 mm RHAe

T-80UD front hull/glacis KE protection: ~600-700 mm RHAe

M1A2 (with improved armor package*) front hull/glacis KE protection: ~550+ mm RHAe    (this could also be around 470 mm RHAe KE)

 

This is pure speculation and highly questionable (aside of the fact that RHAe is a bad metric). The M1A2 has no DU armor in the hull, so a better replacement for the DU armor doesn't result in improved hull protection. The glacis armor remains 38 mm steel even today... no way that could reach 500 mm protection against APFSDS rounds. T-80UD's protection is relying on the question whether Kontakt-5 works against the APFSDS round in question or not. 

 

Regarding the Challenger 2 and the Leclerc, we do have no accurate information. 500 mm KE protection seems feasible and also was planned, but as Wiedzmin wrote, the UK was not sure if this requirement could be met. They also considered increasing the protection requirement in the early stages of the program (from 500/800 mm vs KE/CE to 600/900 mm vs KE/CE), but this idea was rejected for being impossible to meet.

 

Regarding the Leclerc, we have probably the least intel. When an early prototype of the Leclerc was offered to the UK in 1987, its protection (420 mm vs KE along a 20° arc at the turret front) was considered worse than that of the Leopard 2A4 with 1988 armor package. The protection of the Leclerc S1 in Sweden wasn't much higher (450 mm steel equivalent protection at 20° angle for 50% of the area in Swedish simulations).

 

6 hours ago, Laviduce said:

Given that the export M1A2 front turret armor was rated at "very good", second only to the Strv 122,  I would rank the turret Cheek armor around 700-800+ mm RHAe. Not Quite Strv 122 levels of protection but still considerably better than Challenger 2E and Leclerc UAE at around 600-650+ mm RHAe.

 

Outside of video games, nobody is focused on protection directly from the front only. The real question should always be, what type of ammunition is the manufacturer of the tank expecting to be used in the near future?

 

The Leopard 2A5/Stridsvagn 122 achieved its extremely high protection level due to the fact that it basically combining two separate armor upgrades (Type D internal armor and MEXAS-H add-on armor) in a single package, which was even modified further to meet to the Swedish protection requirements (as Sweden wanted to purchase an existing tank instead of buying a next-gen tank). The original German plans were quite different and the original protection requirements were likely surpassed quite a bit.

 

The Type D armor package designed for the Leopard 2 was apparently meant to stop LKE I APFSDS, which follows the tendency of Germany to use its own rounds as stand-ins for contemporary Soviet designs (i.e. 105 mm and 120 mm APFSDS rounds instead of 100/115/125 mm APFSDS rounds). As the Type D armor was designed for the 1990s, stopping a round expected to be fielded in the 1990s (at relatively long ranges) seems reasonable.

 

The Challenger 2 was designed to resist monobloc APFSDS rounds with WHA or DU staballoy penetrator, believed to reach a penetration of 530 mm at the muzzle. This was a reasonable estimate for improved Soviet ammunition for the T-64/T-72/T-80 at the time.

 

Regarding the M1A2 Abrams, it has been claimed in an earlier topic in this forum, that an early version of the Israeli M711 APFSDS was used as reference threat. This seems quite possible and also very reasonable, given that the M711 has basically been the top-performing APFSDS available to the basic T-72 for more than twenty years after the end of the Cold War.

 

But why would the Abrams suddenly require a massive upgrade in effective protection against APFSDS rounds?

 

 

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My Leclerc estimates are based on the Swedish vulnerability plot. Not including weak zones, it gives the Leclerc S1 a protection level of up to around 550 mm RHAe in the frontal 60 degree arc behind the original export M1A2 at 600 mm RHAe. If the upper front hull/glacis used similar technology and techniques I would not be particularly surprised if the hull KE protection values of around 500 mm RHAe were obtained. It seems, just in case of the flat turret concept, the special armor in the hull was also confined in rather concentrated zones. This approach could have helped to push the protection levels past similar vehicles (e.g. Leopard 2A4, M1A1, etc.) while sacrificing special armor protection coverage.

 

Concerning the Abrams I was talking about the "beak" glacis and not the upper front hull glacis.  I also did not mean the original export M1A2 but the 1998-2000 export model.  There seems to be an indication that the front hull armor of later M1A2 tanks (Export 2, SEP models) was "improved".

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I also grabbed the wrong image earlier with the CR2 mantlet description. The side triangles, "envelopes", were described separately:

 

Spoiler

[image removed]

 

He also gave this description which matches the images seen above:

Quote

The mantlet envelopes though (the triangular shaped bits either side of the barrel and TISH barbette are 250mm thick (LOS) and hollow in the rear/lower corner (when viewed from the front) which is where the TISH cables feed through into the turret through the same aperture as the GAS.

 

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3 hours ago, SH_MM said:

 

Well, it depends on the exact armor layout. The problem is that the different slope will affect the effective protection provided by most materials (sloped steel being weaker against APFSDS rounds when sloped, unless sloped very high; NERA being less effective perpendicular to the threat, while ceramics are better in exactly the same situation).

 

If one does not account for these factors, the volume will be used less effectively. In case of the Leopard 2 (at least the Leopard 2AV) and the M1 Abrams, the shape of the hull armor cavities do not correspond to the actual shape/sloping of the armor arry. In case of British tanks, the shape of the armor cavities is less suited for such solution, hence the difference between the shape of turret and hull might be more relevant.

 

 

That is quite possible, though IMO the picture quality is too poor to make an accurate judgement.

 

 

British research on DU armor suggests that thin plates used in a NERA-like configuration are prefered, at least such an array (using very thin DU plates and poly-carbonate inter-layers) was revealed in a British publication:

KBNcRQI.jpg

Note that this armor is optimized for KE and each sandwhich plate is less than two inches thick. Both DU plates amount to less than half of the multi-layered plates thickness.

 

The US Abrams also apparently featured thin DU plates, at least in case of the M1A1 HA and M1A2. There is a 1995 report covering the SMC (Specific Manufacturing Capabilites) located at Idaho National Engineering Laborary, i.e. a facility run by Lockheed-Martin and the US Department of Energy specifically to manufacture DU elements for the M1A1 HA and M1A2 tanks. The reports speciifcally mentions that the shears (shears have to be used to prevent DU dust potentially contaminating the worker's lungs) are rated for DU plate thicknesses of 0.625 and 0.375 inches. This would suggest that at least some parts of the DU armor arrays of the M1A1 HA and M1A2 use DU plates with a thickness as low as 9.525 milimeters.

 

sxW7Hyb.png

 

 

They are backplates, which is why it is extremely unlikely that they are made out of DU. DU is way to heavy.

 

How thick do you think is the backplate? To me it seems to be in the area of 40 to 50 mm (not accounting for slope).

  Hide contents

nTOYbh0.jpg

L8PO0h7.jpg

 

The problem is that given the slope of the hull, you look at as much weight as a 188 to 235 mm thick steel plate (assuming a DU staballoy with a density of 18.5 kg/cm³). 188 mm thick steel weighs ca. 1,500 kilograms per m², a 235 mm steel plates weighs ca. 1,880 kilograms per m² . Given the size of the area covered by the backplate, that would already be more weight for the backplate than the Challenger 1 had for total Burlington armor on the hull front. Basically there would be no weight left for anything else (such as NERA layers required to reach the desired 800 mm protection against shaped charges). Without additional layers, the DU plate with additional steel front and back plates also would fail to reach the desired level of protection.

 

So either the backplate is not made of DU or there has been a massive, currently unexplained weight reduction in hull components and/or the existing steel armor.

 

The problem also exists for the turret. Turret armor slope is not as extreme, but the backplates are also fitted to the turret sides. Basically more than half of the turret armor's weight would be related to the backplates.

 

 

Other materials have to be used, as DU is simply to heavy.

Which other examples of DU being mounted as a plate for armor applications do you know?

 

Correct me if I am wrong but I think that DU can not be used as a structural material welded together with steel. I may have read an outdated info but I found only a diffusion welding with vanadium filler as a possible way how to weld DU and steel together (in relatively small thickness). I doubt it can be used for any large structures such as tank hulls or turrets. 

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10 minutes ago, Beer said:

 

Correct me if I am wrong but I think that DU can not be used as a structural material welded together with steel. I may have read an outdated info but I found only a diffusion welding with vanadium filler as a possible way how to weld DU and steel together (in relatively small thickness). I doubt it can be used for any large structures such as tank hulls or turrets. 

 

Doesn't the NRC license for the M1A2 DU mention it being encased in stainless steel? I would assume it needs to be insulated from other metals to avoid any galvanic action.

 

Spoiler

unknown.png

https://www.nrc.gov/docs/ML0605/ML060590665.pdf

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2 hours ago, Laviduce said:

My Leclerc estimates are based on the Swedish vulnerability plot. Not including weak zones, it gives the Leclerc S1 a protection level of up to around 550 mm RHAe in the frontal 60 degree arc behind the original export M1A2 at 600 mm RHAe.

 

This is not the case. In my opinion your interpretation of the data is questionable, if you argue that the Swedish computer simulations would show this. Based on the diagram, the armor protection is less than 550 mm at 20° angle - and that is for the right side, where most of the gunner's sight weak spot is covered by the gun.

 

y3u2nlg3pvn21.jpg

 

In the simulation ~18% of the armored surface of the crew compartment reach at least 700 mm KE when seen at a 20° angle; none of which includes the left turret front module.  ~39% of the armored surface of the crew compartment reaches at least 600 mm KE when seen at a 20° angle - or 21% without including the previously mentioned area. The problem is that the left turret front armor module covers ca. 37-40% of the total surface area visible at this angle. This suggests that the KE protection of the left turret front armor module at a 20° angle is less than 500 mm. I do not see how this diagram can lead to a KE protection of 550 mm steel-equivalency at 30° angle.

 

Curiously this comes rather close to figures cited in the UK's assessement of the Leclerc in 1987/88...

 

2 hours ago, Laviduce said:

It seems, just in case of the flat turret concept, the special armor in the hull was also confined in rather concentrated zones. This approach could have helped to push the protection levels past similar vehicles (e.g. Leopard 2A4, M1A1, etc.) while sacrificing special armor protection coverage.

 

Only that the UK claimed that the Leclerc prototype was not better armored than the contemporary work-in-progress armor package of the improved Leopard 2A4.

 

2 hours ago, Laviduce said:

There seems to be an indication that the front hull armor of later M1A2 tanks (Export 2, SEP models) was "improved".

 

And this indication is what exactly? The weight increase at least went more or less completely to the turret.

 

1 hour ago, BaronTibere said:

Doesn't the NRC license for the M1A2 DU mention it being encased in stainless steel? I would assume it needs to be insulated from other metals to avoid any galvanic action.

 

That also could be a reference to the turret shell/armor cavity walls being made of steel.

 

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1 hour ago, SH_MM said:

 

This is not the case. In my opinion your interpretation of the data is questionable, if you argue that the Swedish computer simulations would show this. Based on the diagram, the armor protection is less than 550 mm at 20° angle - and that is for the right side, where most of the gunner's sight weak spot is covered by the gun.

 

y3u2nlg3pvn21.jpg

 

In the simulation ~18% of the armored surface of the crew compartment reach at least 700 mm KE when seen at a 20° angle; none of which includes the left turret front module.  ~39% of the armored surface of the crew compartment reaches at least 600 mm KE when seen at a 20° angle - or 21% without including the previously mentioned area. The problem is that the left turret front armor module covers ca. 37-40% of the total surface area visible at this angle. This suggests that the KE protection of the left turret front armor module at a 20° angle is less than 500 mm. I do not see how this diagram can lead to a KE protection of 550 mm steel-equivalency at 30° angle.

 

Curiously this comes rather close to figures cited in the UK's assessement of the Leclerc in 1987/88...

 

 

Only that the UK claimed that the Leclerc prototype was not better armored than the contemporary work-in-progress armor package of the improved Leopard 2A4.

 

 

And this indication is what exactly? The weight increase at least went more or less completely to the turret.

 

 

That also could be a reference to the turret shell/armor cavity walls being made of steel.

 

 

 

This is part of my study.  Compared to the FMV model the protection coverage of my model is better at the lower RHA(e) values. Both models converge around 600 mm (35-38% coverage). Post 600 mm RHA(e) values, the coverage in my model falls short on what the FMV modelled:

 

Spoiler

study_model_diagram.png.372cdd429ca656f4

Small correction: I was a bit hasty to include the entire frontal 60 degree arc. After taking a second look,  I have to lower my estimates.

 

The 550 mm RHA(e) value is only being reached within the frontal 40 degree arc. To  get a more favorable protection coverage the values go as low as 450-480 mm RHA(e) in the frontal 60 degree arc. Just to be on the save side, I would say the turret  protection is around 450 mm RHA(e) in the frontal 60 degree arc.

 

Spoiler

study_model_diagram2.jpg.e12d5478cde6b8c

 

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12 hours ago, Wiedzmin said:

xU4axoyn2kM.jpg?size=815x534&quality=96&

 

frontal packs of turret much smaller with huge weak zones + there is no proves that any real improvement was made for front hull armour since CR1 

 

  

and what you expect from mantlet ? 

 

SMk3pNbS2Qk.jpg?size=1200x900&quality=96

 

O2wUtI6Xj9c.jpg?size=1200x900&quality=96

 

 

 

 

I didn't expect anything at all for the mantlet. I've seen a similar photo to this before it's just that there are furious internet arguments about this specific portion of the tank being armored or not, but thank you for the extra photos.

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16 hours ago, Laviduce said:

This is part of my study.  Compared to the FMV model the protection coverage of my model is better at the lower RHA(e) values. Both models converge around 600 mm (35-38% coverage). Post 600 mm RHA(e) values, the coverage in my model falls short on what the FMV modelled:

 

In other words: it is not based on the Swedish computer analysis. Your 3D model of the Leclerc might be a more accurate than the one of the FMV, but the FMV's data is only valid for the Swedish 3D model.

 

The armored surface (the red and green colored area) on your model is roughly 8% smaller than the armored surface of the model used by the FMV. That alone leads to a big disconnect in applicability with the FMV's data.

 

A further important factor is, that about 5% of the total surface that reaches 700 mm KE protection (or ~28% of that surface) in the FMV model is missing in your model. It is relevant to keep in mind that the graph's from the FMV show the amount of the total armored surface reaching at least the protection level plotted on the x-axis.

In other words: if 38% of the surface the FMV's model reach 600 mm vs KE, then this includes 18% of the surface that reaches even 700 mm steel-equivalent protection against APFSDS rounds whereas the remaining 20% are reaching between 600 and 700 mm KE protection. So even if your model and the FMV had the very same armored surface (which they don't have), the percentages of the armored surface reaching a protection level of X mm KE are not comparable - e.g. when 36% of your model reach a protection level of X mm KE, this would be equal to 41% of the surface plotted in FMV's graph reaching the same protection level.

 

Then there is the issue that your own figures show that - even ignoring all said previously - your model does simply not match the FMV's data. In your model, 49% of the armored surface reach a protection level of 550 mm steel equivalency against APFSDS rounds at 20° angle, but in the FMV's computer simulation it was only 43%. In your model 13% of the armored surface at 20° angle reaches 700 mm KE protection, in case of the FMV's it should be 18%. Even the "convergence" at 600 mm KE (with your model reaching 36% and the FMV's one reaching 38%) has quite a big margin of error (5%). However there is no real convergence, you are just looking at two functions with different gradients that have an intersection at some point close to 600 mm KE protection. If there was a convergence, the margin error would not increase when moving further along the x-axis.

 

When using the FMV's data, your model is biased for higher protection by reducing the total surface and at the same time reducing the area reaching 700 mm KE protection by a disproportional amount.

 

Last but not least you are putting to much faith into the graph from the FMV. It seems to be the result of a limited amount of calculations (i.e. at least for every point where the gradient changes) that has been interpolated. Otherwise there would be more significant changes instead of a steady gradient between every of the measured points in the graph.

 

16 hours ago, Laviduce said:

The 550 mm RHA(e) value is only being reached within the frontal 40 degree arc. To  get a more favorable protection coverage the values go as low as 450-480 mm RHA(e) in the frontal 60 degree arc. Just to be on the save side, I would say the turret  protection is around 450 mm RHA(e) in the frontal 60 degree arc.

 

If you are happy with the interpolated values and are considering an armor coverage of 50% as "protected against X", then you can see in the original FMV graph that 50% of the surface provides protection against APFSDS rounds with ~480 mm penetration against steel armor - not 550 mm.

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2 hours ago, SH_MM said:

 

In other words: it is not based on the Swedish computer analysis. Your 3D model of the Leclerc might be a more accurate than the one of the FMV, but the FMV's data is only valid for the Swedish 3D model.

 

The armored surface (the red and green colored area) on your model is roughly 8% smaller than the armored surface of the model used by the FMV. That alone leads to a big disconnect in applicability with the FMV's data.

 

A further important factor is, that about 5% of the total surface that reaches 700 mm KE protection (or ~28% of that surface) in the FMV model is missing in your model. It is relevant to keep in mind that the graph's from the FMV show the amount of the total armored surface reaching at least the protection level plotted on the x-axis.

In other words: if 38% of the surface the FMV's model reach 600 mm vs KE, then this includes 18% of the surface that reaches even 700 mm steel-equivalent protection against APFSDS rounds whereas the remaining 20% are reaching between 600 and 700 mm KE protection. So even if your model and the FMV had the very same armored surface (which they don't have), the percentages of the armored surface reaching a protection level of X mm KE are not comparable - e.g. when 36% of your model reach a protection level of X mm KE, this would be equal to 41% of the surface plotted in FMV's graph reaching the same protection level.

 

Then there is the issue that your own figures show that - even ignoring all said previously - your model does simply not match the FMV's data. In your model, 49% of the armored surface reach a protection level of 550 mm steel equivalency against APFSDS rounds at 20° angle, but in the FMV's computer simulation it was only 43%. In your model 13% of the armored surface at 20° angle reaches 700 mm KE protection, in case of the FMV's it should be 18%. Even the "convergence" at 600 mm KE (with your model reaching 36% and the FMV's one reaching 38%) has quite a big margin of error (5%). However there is no real convergence, you are just looking at two functions with different gradients that have an intersection at some point close to 600 mm KE protection. If there was a convergence, the margin error would not increase when moving further along the x-axis.

 

When using the FMV's data, your model is biased for higher protection by reducing the total surface and at the same time reducing the area reaching 700 mm KE protection by a disproportional amount.

 

Last but not least you are putting to much faith into the graph from the FMV. It seems to be the result of a limited amount of calculations (i.e. at least for every point where the gradient changes) that has been interpolated. Otherwise there would be more significant changes instead of a steady gradient between every of the measured points in the graph.

 

 

If you are happy with the interpolated values and are considering an armor coverage of 50% as "protected against X", then you can see in the original FMV graph that 50% of the surface provides protection against APFSDS rounds with ~480 mm penetration against steel armor - not 550 mm.

Thank you for your feedback !

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On 5/26/2021 at 6:44 AM, SH_MM said:

 

After seeing Wiedzmin's photo from the damaged turret underside, you can see the array itself actually and to me it does seem that DU would simply take too much space in that LOS to achieve a protection level of what is approximately 650 or so KE. However this leaves a large hole, you can actually see a 2nd plate of similar style to the back plate in that array towards the front which now begs the question what is this plate made of to actually help achieve the on paper specified effectivity of armor. In my opinion now a much higher than average metal has to be used. 

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On 5/26/2021 at 2:28 AM, Wiedzmin said:

and there is british reports with "can we really do that?" so...

 

 

Where is this found? As far as I know the 'requirement' was there but I don't recall seeing something about the actual implementation of the requirement

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13 hours ago, Korvette said:

Where is this found? As far as I know the 'requirement' was there but I don't recall seeing something about the actual implementation of the requirement

Chieftain replacement report AT milestone two SR(L) 4026,Chieftain replacement EPC paper  and other reports 

 

 

unknown.png

 

  

On 5/26/2021 at 8:12 PM, SH_MM said:

550 mm at 20° angle

unknown.png

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Didn't know the British assessment of the Leclerc was from 1990; that's the same year the final prototypes and first pre-series vehicles were constructed. So it seems that the original series version of the Leclerc was not better protected.

 

On 5/26/2021 at 12:02 PM, SH_MM said:

 

It is an article published in the 372 issue of the Greek magazine Ptisi & Diastima ("Aviation and Space"), which despite its name covers also military technology and news in the land and naval sectors. It was published in May 2017.

 

I don't speak Greek, so I used the summary of Scout-TheDeadDistrict.blogspot.com (now defunct) as mentioned by Laviduce. I did however bother to fact check it as good as possible - for someone who doesn't speak Greek and found several references on the Ptisi & Diastima website (including the table of contents of the 327th issue of Ptisi & Diastima), an teaser article for the Leopard 2 HEL program coverage. When I originally checked Ptisi & Diastima, their website was still different and I found several (low quality) preview pages from the relevant article ("Η αλήθεια για το πρόγραμμα Leopard 2HEL· μια 20ετής αναζήτηση…") - unfortunately I cannot find them at the moment.

 

The original article is 26 pages long and contains (based on the preview images) quite a bit of additional info (lots of texts, but also tables and photos) that didn't make it into The Dead District's blog article.

 

Okay, the section of the article covering the characteristics of the evaluated tanks is basically the same section that was posted on Scout-TheDeadDistrict.blogspot.com, there are only minor differences, which are probably caused by the translation software.

Regarding the Challenger 2E, the text is more or less limited to that:

 

s6M2hpr.png

Regarding Challenger 2E:

  • it was a negative suprise
  • high rate of transmission failures
  • not performing better than the 1,200 hp version was believed to perform, despite featuring a 1,500 hp EuroPowerPack
  • the "much advertised" armor protection was found to be lower than that of the M1A2 and Leopard 2A5S despite similar weight - and only "a little better" than that of the Leclerc tank that was 10 tons lighter
  • low accuracy, the rifled gun and the three piece ammunition were also seen as drawbacks

Most of the article covers the Greek tank program, the Leopard 2 program in general and the Leopard 2A6 HEL production. There are a few new aspects that I didn't know of, e.g. that the M1A2 being offered for a very good price in 1996 but the high inflation rate of the drachma would have made that unprofitable by 2000.

 

In the end not only the Leopard 2A5 and M1A2, but also the Leclerc and Challenger 2E were considered adequate - so their manufacturers were asked to bid.

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