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I'm too lazy to check; what model of Abrams upgraded the thermal sight?  The earliest thermal sight (TIS) was considered slightly inferior to the TTS retrofitted to the M60A3.  I think this was a legacy of the Abrams being a "cheaper" MBT after the implosion of the MBT-70 program.

Hopefully the British crews weren't doing anything wildly irresponsible with that single-piece ammunition like lap-loading it the way they were accustomed to with sabot rounds for their L11s!

 

I am also dubious that the Abrams has a particularly easy powerpack to swap.  @Xlucine had mentioned that Challenger's powerpack was significantly slower to change out.  I suspect that the British crews would have been just as blown away by a Leo 2.

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1 hour ago, Collimatrix said:

I'm too lazy to check; what model of Abrams upgraded the thermal sight?

 

M1A2, it's interesting to read something from 1989 and know what complaints have long been rectified (boiling vessel!).

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dOy_IvdfFX4.jpg

 

This is an extract from a British document from 1988. Apparently the British military believed that the "uparmoured Chieftain" has better frontal protection than a Leopard 2, while the Challenger 2 has inferior protection against KE than an uparmoured variant of the Abrams announced "recently" by 1988 standards. IMO the latter refers to the DU armor upgrade of the M1A1 HA. Interesstingly this is said to provide better protection only over a narrow frontal arc... does this mean that the Abrams' armor array does not provide full protection of the 60° frontal arc? At least other images also imply the that...

 

QvTYhpl.png

Sg5RQIw.png

The graphic above is from a Swedish document and might have been taken from an official M1 sales/info brochure, as Sweden tested the Abrams. Based on this, the "turret front" arc for the M1A2 covers the crew compartment only at angles of about 17-21° to each side of the centerline.

 

As for the Leopard 2 and the Chieftain: Honestly I am quite confused. In 1988 the second generation armor package for the Leopard 2 was adopted (based on German marketing documents send to Sweden) - if that is true, the British assessment might still be based on an earlier Leopard 2 model with the original first generation armor package from 1979. That this would provide lower protection than the Challenger 1, Challenger 2 and M1A1 HA Abrams is quite easy to believe (weight 55.15 tons vs 61-62.5 tons).

Apparently the document does not disclose what tank variant exactly is meant with the uparmored Chieftain and how armor protection was rated (disclosed figures, estimates, weighting for KE/CE protection, etc).

I don't believe that they meant the Chieftain with Stillbrew armor, based on the fact that its protection against shaped charges seems to be extremly weak (no composite armor on the hull, except for a bit Stillbrew armor at the turret ring) and at best should have comparable protection at the turret (weight of both tanks is  very similar, but the Chieftain's turret is made from inferior cast steel, that offers less protection per weight).

 

Maybe the British military was still toying with the idea of upgrading Chieftain tanks? In the end they had concrete plans for upgunning the Chieftain with the L30 tank gun and adopting the Challenger 2's FCS, which were only canceled after the end of the Soviet Union. So it seems possible that the uparmored Chieftain statement is refering to a hypothetical armor upgrade that was not adopted in service. Maybe something similar to the original Chobham armor upgrade concept form the 1970s, the Chieftain Mark 5/2 or the Chieftain 900:

 

Chobham+Type+1.png

post-11038402-0-63974600-1409039850.jpg

 

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18 hours ago, SH_MM said:

dOy_IvdfFX4.jpg

 

This is an extract from a British document from 1988. Apparently the British military believed that the "uparmoured Chieftain" has better frontal protection than a Leopard 2, while the Challenger 2 has inferior protection against KE than an uparmoured variant of the Abrams announced "recently" by 1988 standards. IMO the latter refers to the DU armor upgrade of the M1A1 HA. Interesstingly this is said to provide better protection only over a narrow frontal arc... does this mean that the Abrams' armor array does not provide full protection of the 60° frontal arc? At least other images also imply the that...

 

QvTYhpl.png

Sg5RQIw.png

The graphic above is from a Swedish document and might have been taken from an official M1 sales/info brochure, as Sweden tested the Abrams. Based on this, the "turret front" arc for the M1A2 covers the crew compartment only at angles of about 17-21° to each side of the centerline.

 

As for the Leopard 2 and the Chieftain: Honestly I am quite confused. In 1988 the second generation armor package for the Leopard 2 was adopted (based on German marketing documents send to Sweden) - if that is true, the British assessment might still be based on an earlier Leopard 2 model with the original first generation armor package from 1979. That this would provide lower protection than the Challenger 1, Challenger 2 and M1A1 HA Abrams is quite easy to believe (weight 55.15 tons vs 61-62.5 tons).

Apparently the document does not disclose what tank variant exactly is meant with the uparmored Chieftain and how armor protection was rated (disclosed figures, estimates, weighting for KE/CE protection, etc).

I don't believe that they meant the Chieftain with Stillbrew armor, based on the fact that its protection against shaped charges seems to be extremly weak (no composite armor on the hull, except for a bit Stillbrew armor at the turret ring) and at best should have comparable protection at the turret (weight of both tanks is  very similar, but the Chieftain's turret is made from inferior cast steel, that offers less protection per weight).

 

Maybe the British military was still toying with the idea of upgrading Chieftain tanks? In the end they had concrete plans for upgunning the Chieftain with the L30 tank gun and adopting the Challenger 2's FCS, which were only canceled after the end of the Soviet Union. So it seems possible that the uparmored Chieftain statement is refering to a hypothetical armor upgrade that was not adopted in service. Maybe something similar to the original Chobham armor upgrade concept form the 1970s, the Chieftain Mark 5/2 or the Chieftain 900:

 

Chobham+Type+1.png

post-11038402-0-63974600-1409039850.jpg

 

k8kLP7y.jpg

8zOtgt5.jpg

 

I  am getting the impression that they are talking about the tanks pictured above (Stillbrew Chieftain Mk10, Challenger 1, Leopard 2A4 (early), M1A1, Vickers Mk7/2) The picture seems to have been taken some time in 1990.

 

According to the Challenger 2 book by Osprey the Leopard 2A4 and the other contestants were "current production models". As we know; the latest models of these tanks were the Chieftain Mk11, Challenger 1 Mk3 (minus ROMOR armor), Leopard 2A4 with 2nd gen. special armor, M1A1 HA, Vickers Mk 7/2.

 

There is at least 1 problem with this statement.  The Leopard 2A4 pictured above seems to be one of the Leopard 2A4s that still features the 1st generation special armor. If take a closer look at the heavy side skirt mountings we see that they seem to correspond to the earlier models not the latter vehicles (vehicle 97+ batch 6, batch 7 and batch 8) as seen below.

 

Batch 8 Leopard 2A4:

Leo2A4-KMW-01.jpg

 

It seems that this protection feature above the heavy side skirts was dropped in post 1992 Leopard 2A4s.

 

 

 

 

 

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2 hours ago, Laviduce said:

According to the Challenger 2 book by Osprey the Leopard 2A4 and the other contestants were "current production models". As we know; the latest models of these tanks were the Chieftain Mk11, Challenger 1 Mk3 (minus ROMOR armor), Leopard 2A4 with 2nd gen. special armor, M1A1 HA, Vickers Mk 7/2.

 

There is at least 1 problem with this statement.  The Leopard 2A4 pictured above seems to be one of the Leopard 2A4s that still features the 1st generation special armor. If take a closer look at the heavy side skirt mountings we see that they seem to correspond to the earlier models not the latter vehicles (vehicle 97+ batch 6, batch 7 and batch 8) as seen below.

 

Batch 8 Leopard 2A4:

Leo2A4-KMW-01.jpg

 

It seems that this protection feature above the heavy side skirts was dropped in post 1992 Leopard 2A4s.

 

The British document is from 1988, so it  might contain information on another variant than tested in the UK. But as you said, it appears that they tested the Leopard 2A4 with first-generation armor package.

 

The upper section of the heavy side skirts found on late-productiton Leopard 2A4 tanks was never removed; if you look closer at the tank, you should notice that the complete side skirts are changed. This tank features completely improved side skirts (rear sections made of a high-hardness steel plates rather than rubber-encased perforated plates, lower section of the frontal skirts is thicker and seamless, upper section was added). 

 

You won't find a Leopard 2A4 with such skirt armor anymore, because all hulls were used for the Leopard 2A5. The German Leopard 2A5 tanks were all created by converting Leopard 2A4 tanks. The hulls were taken from the latest batches, because these had the lowest wear (so engine, running gear etc. could be kept), while not much other work had to be done on the hull (maybe swapping out the armor inserts). The original plans from the German army saw a major hull upgrade happening in the third stage of the upgrade (KWS) program (originally schedule for 2008), when the 140 mm gun in a new turret would be added. Then the hull would need to be reworked (due to the 140 mm calibre being incompatible with the existing ammo rack), the hull armor of the Leopard 2A5 prototypes (also used on the Strv 122, Leopard 2A5DK, Leopardo 2E and Leopard 2A6HEL) would be added and the torsion-bars would probably be replaced (to deal with the increased weight). The turrets were taken from the very early batches Leopard 2 tanks, because pretty much everything needed to be changed. The turrets from the late batch Leopard 2A4s were then mounted on the hulls of the early batch Leopard 2s creating so called "hybrid Leopard 2" tanks.

 

leopard_2a5_10_of_28.jpg

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0BTiB7r.png

 

This table is from the CIA report "Egypt and the M1A1 Tank: The Push for Coproduction". It doesn't seem to be very reliable data, but it is interesting to see how the situation on the tank market was judged during the 1980s. The Egyptian military wanted to produce the M1A1 Abrams tank, because the upgraded T-54 and T-55 tanks (called "Ramses") with 105 mm L7 gun and new FCS aswell as the M60A3 were believed to be inferior to the T-72 tank operated in Lybia (which seems to be correct regarding some of the general performance characteristics). The Egyptian military believed that Lybia might be interested in buying the T-80 tank in an unknown configuration. The improvements to Israeli tanks also fueled the desire to adpot a new tank.

 

Aside of the M1A1, the Leopard 2, the AMX-40, the OF 40, the Type 74, the Yugoslavian M-84 and the Vickers Mark 7 were available on the market, however the low budget reduced the Egyptian options to the M1A1 Abrams, which was cheaper thanks to the US government partially funding the Egyptian military modernization. Still the US believed selling the M1A1 to Egypt wouldn't make much of a difference on the geopolitical scale: "Acquistion of the M1A1 probably would not dramatically enhance Egypt's military capabilities in the 1990s", something that is related to the CIA assessment suggesting that the T-72 and T-80 would be able to outgun the M1A1 (no further reasons stated why this would be the case...). The Egyptian military was not expected to be able to make much use of the M1A1 due to them already having maintenance and training problems with the M60A3, which was claimed to be a less complext tank than the M1A1. Due to the Egyptian military still making use of standard Soviet formations, they wouldn't be able to make fully use of the M60A3's capabilities.

 

Apparently the Leopard 2 was somewhat considered by Egypt. The officials from the Ministry of Defence traveled multiple times to West-Germany, although it is highly questionable that Germany would have agreed to sell the tanks to a (former) opponent of Israel. There were plans between a Turkish and Egyptian cooperation to jointly buy the Leopard 2 tanks. CIA assumed that the Egyptian minister also would have suggested a joint production of the M1A1 tank to Turkey. Previously he made public statements of a cooperation between both countries allowing a reduction in the M1A1 price by as much as 40%.

 

The CIA assessment suggests that politics were heavily involved. Egypt wanted to buy the M1A1 tanks, because this would appeal their national pride; they would be on the same level as Israel in terms of their cooperation with the United States. Also the Egyptian minister supposedly assumed that chosing the M1A1 Abrams over other MBTs was a favor to the US government. Canceling the deal was not deemed to be possible in 1987 for the US, as this would damage the USA-Egypt relations and Mubarak might have blocked the Suez canal from being used by US Navy vessels.

 

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Yes. The 90 kph top speed of the T-80 and the 63.8 metric tons combat weight of the M1A1 are also incorrect.

IMO these are copy errors: 63.8 short tons is the combat weight of the M1A1, the author didn't convert it. He apparently also just took the maximum physical armor thickness without slope for the M60A3.

 

 

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Regarding the earlier discussion about the XM1 and the British MBT-80's armor protection, posted by Wiedzmin on Tank-Net: "Why the Brits didn't like the protection of the XM1 tank".

 

2ate2CY.jpg

 

Interesting is the protection of protecting the roof only against artillery fragments and the crew compartment against 81 mm HEAT warheads at 45° angle. I guess the latter might be a reference to the Carl Gustav recoiless rifle (which has 84 mm diameter, so 81 mm warhead diameter seems to be likely). The intervall for the range at which protection against APFSDS shall be provided might suggest, that this is either different for turret and hull (i.e. turret resistant against APFSDS fired from 800 m distance, hull resistant to APFSDS fired from 1,200 m distance) or depends on angle (impact angle 0° = armor resisting APFSDS fired from 800 m; impact angle 20-30° = armor resisting against APFSDS fired from 1,200 m).

 

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

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That's very interesting, but using a single value to represent armor protection is quite a bit lackluster. What exactly is one value meant to show (average protection, maximum protection, protection at the frontal arc, protection at the frontal surface only)?

 

  • The British underestimated the armor protectiton of Soviet tanks by a lot. T-64 and T-72 should have some 350 mm RHA equivalent armor on the UFP and turret armor up to 450 mm. The T-72A, T-80(B) and later tanks would have even higher levels of protection.
  • The Leopard 2's armor value is suprisingly low. It makes me wonder what the British military knew about the Leopard 2 in 1978. Previously there was quite a bit of cooperation (UK presenting Chobham to Germany in 1970, Germany and UK developing a tank in 1972-1976/77), but the latter all ended about the time the Leopard 2 was redesigned to accept special armor. The Leopard 2K has 38 mm high-hardness steel + 127 mm airgap + 84 mm RHA sloped at 25° at the turret front, which turns out to be 288.6 mm steel along the line of sight. So assuming a slightly higher efficiency than RHA (due to it being spaced armor with high-hardness steel), it already should reach protection equivalent to 300 mm steel armor against APFSDS ammo (at 0° impact angle). I'd be quite surprising if the Leopard 2 retained this level of KE protection (with a greater coverage) on the 2AV and later models...
  • The Shir 2 has a power-to-weight ratio of 18 bhp/ton with the 1,200 hp CV12 engine, so it should weigh something between 63 to 65 metric tons... that's quite a bit of weight given the poor level of protection. The Shir 2 was used to create the Challenger 1 (!), which has a weight of only 62 metric tons. Unless the armor composition was changed, this would mean the Challenger 1 had the lowest KE protection per weight (although it is not exactly clear how the protection was defined) and be worse protected than the M1 and M1A1 Abrams.

 

1417808518-leopard-2-armor-capabilities.

This graphic was published in a 1986 German book. The Leopard 2 is meant to resist (at the turret) a 125 mm APFSDS at 1,500 m range. That sort of makes 300 mm RHA impossible, unless this is a minimum or average value (though the latter would mean, that the hull would have less than 300 mm RHA equivalent protection, which also doesn't seem realistic...).

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@Methos

Confirm that german special amrmour was not tested in USA:

https://babel.hathitrust.org/cgi/pt?id=msu.31293016483954;view=1up;seq=1

 

marevelous document about 105mm vs 120mm in USA:

https://babel.hathitrust.org/cgi/pt?id=uc1.31210024740399;view=1up;seq=1

"we know that 105mm is shit but it's cost effective"

 

BTW: Im agree that Leopard 2 is understimeted a lot. IMHO whole think is taken from T14 turret values or fact tahat in Leopard 2AV tehere was no special armour - just "cavity" made by frontplate and backplate - X-rayed by Americans who "discover" there is no special armour there. So propably (it's only my assumption) value for Leo2 is taken from XM1 whit thinner backplate and frontplate in leo-2 (2x 45mm RHA)

IMHO there is no other logical explanation of sucht value

 

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1 hour ago, Sovngard said:

Where did this come from ?

 

1520357157-m1a1-ha-protection-level.jpg

 

This is identical to the diagram I posted earlier (with a lot less pixels) coming from a presentation on the Swedish tan trials. It seems that the protection level was censored in the Swedish presentation (because it is public access). I guess somebody dug this up out of the Swedish archives? But the file name suggest that it shows the M1A1 HA...

 

That said, it seems to be legit. It would confirm my believes on the armor protection of modern tanks being hugely exaggerated and matches some of the earlier mentioned requirements stated in the British documents.

 

 

PS:

wCTwnfc.png

This is another photo from a Swedish presentation. Note how the background matches!

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7 minutes ago, SH_MM said:

 

That said, it seems to be legit. It would confirm my believes on the armor protection of modern tanks being hugely exaggerated and matches some of the earlier mentioned requirements stated in the British documents.

 

 

PS:

wCTwnfc.png

This is another photo from a Swedish presentation. Note how the background matches!

 

 

It depends on how much improvement you think has occurred in the efficiency of NERA arrays in the past few decades.  If there has been substantial improvement, then the Western tanks with the most recent armor upgrades probably enjoy a considerable lead.  If there hasn't been, then they're probably all at about the level shown above.

How the hell is the driver supposed to egress in that Leclerc?

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Well, I didn't mean the armor of current tanks, but older variants. Some claim that the M1A1HA has 600-700 mm steel equivalent hull armor vs KE and 800 mm steel equivalent turret armor vs KE. I do believe a lot of modern tanks have similar protection levels -  the German Leopard 2A5 and 2A6 tanks made use of Leopard 2A4 hulls, so the protection is probably about 300-450 mm vs APFSDS ammo. When fitted with applique armor (or newer inserts), the protection level should be higher.

 

Swedish tests using the MEXAS-H armor (on the hull aparently a single heavy NERA sandwich with lots of slope) from IBD Deisenroth (locally made by Åkers Krutbruk under licence) showcased an increase in armor protection by 50 to 100% in case of the M1A1 hull. This armor is also fitted to the hulls of more modern Leopard 2 variants (incl. the Strv 122). The Leclerc was to be fitted with a wide array of MEXAS armor (turret front armor similar to the Leopard 2A5, side armor similar to the Leopard C2 from Canada).

 

strv_ny-16.jpg

 

7 minutes ago, Collimatrix said:

How the hell is the driver supposed to egress in that Leclerc?

 

The Leclerc was some paper design utilizing the MEXAS armor, it probably was not very optimal. I guess the turret needs to be turned to the side, just like on some Leopard 2 variants.

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11 minutes ago, SH_MM said:

 

This is identical to the diagram I posted earlier (with a lot less pixels) coming from a presentation on the Swedish tan trials. It seems that the protection level was censored in the Swedish presentation (because it is public access). I guess somebody dug this up out of the Swedish archives? But the file name suggest that it shows the M1A1 HA...

 

That said, it seems to be legit. It would confirm my believes on the armor protection of modern tanks being hugely exaggerated and matches some of the earlier mentioned requirements stated in the British documents.

M1_M1_IP_M1_A1_M1_A2.jpg

 

If we can presume that the diagram, and this is accurate, don't we now know how effective the composite armor is compared to RHA?

 

Example:
Side turret armor is 400mm thick, with a protection level of 380mm, equals 0,95 as effective per millimeter vs RHA vs CE.

 

Also, it seems there is no protection gained for the turret side armor to be at 45 degrees, compared to 90 degrees?
 

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3 minutes ago, Xoon said:

 

Also, it seems there is no protection gained for the turret side armor to be at 45 degrees, compared to 90 degrees?
 

 

The efficiency of NERA arrays is heavily dependent on what angle they get hit at.  So it really depends on exactly how the sandwiches are oriented within the array.

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      O-Kay! Now we have some data. It looks like at 2,000 yards, my projectile holds about 2,800 ft/s striking velocity. It's important to note here that what we really care about isn't the striking velocity of the projectile per se, but the velocity and energy of the projectile's core. The core is what's actually doing a lot of work to the armor, so for now let's stop thinking in terms of the whole projectile, and take a look at these two cores, that of the M304 90mm HVAP, and that of my 85mm APCR round. The core of the 90mm M304 is an approximately 8 pound lump of tungsten-carbide that is about 45mm in width. My penetrator is also 8 pounds, but it's longer and thinner in proportion - just 40mm wide, rather than 45mm. This means my penetrator will penetrate more armor at a given striking velocity, and we can estimate how much more by taking the specific energy of the rounds and comparing them. That is, the energy in Joules of the penetrator alone, divided by the penetrator's diameter squared:
       

       


      So the specific energy at 2,000 yards is about 826J/mm^2. Now, we need to find out at what impact velocity the M304 penetrator produces this same specific energy. Do do that, we go backwards, using the figures for M304:
       

       

       
      Therefore, the equivalent impact velocity for my 85mm APCR round at 2,000 yards is 3,150 ft/s for the M304. That means, in theory, that the M304 would have to impact a target at 3,150 ft/s to produce equivalent penetration of RHA to my 85mm APCR striking at just 2,800 ft/s.

      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.
       
       
    • By Mighty_Zuk
      Now that we know the Challenger 2's Life Extension Program won't include a new gun, there's news coming in that the Warrior's modernization program is highly likely to be cancelled:
      Axe Hangs Over UK Warrior Upgrade.
       
       
    • By Walter_Sobchak
      Since Xlucine suggested it in the general AFV thread, here is a new version of the old Tank ID thread that used to exist at the WoT forums, back before the great exodus to SH.
       
      The rules are simple.  Post a picture of some sort of AFV and everyone has to try to name what it is.  Try to avoid posting a new picture until the previous picture is identified.  Generally, the person who was first to correctly ID the picture in question gets to post the next picture, unless they want to pass.  If a picture is not ID'd in a day or two, the person that posted it should say what it is and bask in their own sense of superiority.   They should then post a new picture for the sake of keeping the thread moving.  Please, no fictional tanks, paper napkin drawings that never made it to prototype or pictures where the vehicle in question is obscured or particularly hard to see.  Also, if posting a picture of an unusual variant of a relatively common vehicle, be sure to note that you are looking for the specific variant name, not just the general family of vehicles it belongs to (for example, if I post a picture of a Panzer IV with the hydrostat drive, I would say in the post something like "What makes this Panzer IV unusual?" since everyone can ID a Panzer IV)
       
      It is perfectly ok to shame those that make spectacularly wrong guesses.  That's just how we roll around here.  
       
      I'll start 
       

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