Iron Drapes

What an odd photo

According to the technical manual for the BMP-3, maximum traverse speed is 35 deg/sec in automatic mode with "overcharge", and maximum traverse speed in the semi-automatic mode is also 35 deg/sec. Not really sure how they came up with that. Turret traverse rate for BTR-82 is unknown, sorry. My best guess is that the turret uses the same motors as the BMP-2 and BMD-2, so the max traverse rate could be 30 deg/sec or more. Automatic mode is the default mode for day to day combat. Semi-automatic is for anti-air only, because it severely degrades accuracy in exchange for faster acceleration and faster top speed.

Chinese biathlon team for Day 3 did not perform very well on the shooting range. Only 1 out of 3 shots connected with the target:

It's weird that they could incorporate NERA into the turret but not the hull until much later in the production run. Any idea why?

Well, it depends on the modification, but the two b&w photos given by Militarysta definitely show nothing but steel plates.

That's just spaced steel plates, isn't it?

I see. This is very clear now, thank you.

Yes, and that is the primary (perhaps only) influence of bulging armour. From what I know, it depends on what sort of material is used in the sandwich layer. The rate of energy transfer differs from material to material, and some reach their peak very quickly. Best guess is that it is simply a matter of optimization. It would be inherently better to have more spacing, as that would be more efficient in terms of mass, but for bulging armour using certain sandwich materials, it may be more efficient thickness wise to stack them more closely. You have a heavier, but slightly more protective array. As for arrays with thicker front plates than back plates, that is easily explained. "In pursuit" or "forwards" type NERA armour where the bulging plate expands in the same direction of travel as the projectile is more effective than "In retreat" or "backwards" type NERA armour, where the bulging plate expands against the direction of travel of the projectile. These pictures can tell the tale better than I: It would be more beneficial to have a bias in the direction where the NERA plate bulges. In the case of the T-72B, the NERA can only bulge in one direction. The front plate is too thick and too heavy to move at all. More modern designs may be better optimized for certain threats, but I don't really know much in the way of specifics.

Second hand source, unfortunately: http://below-the-turret-ring.blogspot.my/2017/01/early-m1-abrams-composite-armor.html "A common design principle according to Dipl.-Ing. Rolf Hilmes, who formerly worked at the German BWB, and according to a presentation from the British Defence Science Technology Laboratory (DSTL), is to incorporate a further heavy layer in front of the armor array, which servers to disrupt (shatter/break) the projectile, before the fragments enter the NERA array."

Hi everyone. This is my first post! I'm the guy behind the Tankograd blog https://thesovietarmourblog.blogspot.com/ Mike E, which I think is a familiar name to some of you, used to help me out there. I've done some research into NERA armour in order to better understand the armour of the T-72B, but I definitely don't pretend to know all about it. I've posted some stuff on NERA in my blog's T-72 article, but I'll repeat the most relevant bits here. According to Rolf Hilmes, adding a heavy armour plate in front of the NERA plate boosted the overall effectiveness against KE projectiles. No idea how true this is, but the guy that said it is a world expert on the topic, so hey. As far as I can tell, the heavy plate presumably contributes by fracturing or chipping part of the projectile before it enters the NERA plate, where it is further damaged, but to be honest, I don't know the exact mechanism. Comparisons between independent research involving NERA plates of the same configuration but with different bulging plate hardness has shown that the hardness of the bulging plates directly affects the ability of the NERA armour to disrupt shaped charge jets. So using titanium or aluminium is actually very counterproductive. It is better to use high hardness steel sheets. We must not forget that even though titanium and aluminium may sometimes have better ME than steel, you need quite a large thickness to achieve the same relative armour thickness. When we are talking about bulging plates, thick = bad. Thick plates are very stiff, and that makes it difficult for it to be bulged by the interlayer. But this is not a problem if the objective is to feed as much material as possible into the path of the projectile, right? The thing is... ... the point of NERA probably isn't to feed material for the projectile to penetrate. It is to impart lateral forces. With that in mind, I think that it is better to have more space. This enables you to impart forces on a bigger area of the projectile.