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SH_MM

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  1. This rendering is from the DTR Magazine special that was released on the day of the KF41 reveal at Eurosatory... The Puma is not a Rheinmetall product, but a joint-venture managed by PSM (Rheinmetall & KMW). Rheinmetall Active Protection (previously ADS Gesellschaft für aktive Schutzsysteme mbH) is also a joint-venture (between Rheinmetall and U. Deisenroth's two daughters; previously between Rheinmetall and IBD Deisenroth Engineering). I don't know for sure, but it seems that the intellectual property for the Puma is being held by the German military. To my knowledge all Puma IFVs that have been presented in the past years on various expos around the globe were actually owned by the German military. That probably limits the options for the Puma to be showcased with ADS and other gadgets. As for the Lynx family: it always was offered in a configuration as marketed to a customer. That's why they painted them in Australian (KF31) and Czech (KF31 and KF41) camouflage pattern. The ADS is not the only Rheinmetall-made component that is missing from the Lynx prototypes: they don't have Rheinmetall's thermal camouflage (Solar Sigma Shield), they lack a RWS (no Main Sensor Slaved Armament or Fieldranger RWS), they don't have laser warners, no accoustic sniper location system, etc. They did the same with the Leopard 2 ADT (Revolution at the time): After Indonesia showed interest in the upgrade, a downgraded variant meeting the Indonesian requirements was developed and showcased:
  2. And this shows what? Aside of the author being very much pro-Chieftain, the Leopard 1 is clearly faster at acclerating. This is a cross-country test, so all vehicle results will be closer than on flat surface. Given that the acceleration hasn't stopped at 500 m, it is a rather misleading table. The German military considered 400 m to be the minimum distance of tactical movement.
  3. Yes, would be interesting to see a weight comparison between the two turrets. How heavy was the Chieftain's turret casting (without any other components)? Night fighting in the 1950s, 1960s and early 1970s was a horrible idea for all involved. As all IR sights of the era required an active source, it made the illuminating tank very easy to spot. Also the gunner still has to do his part of the job, it is not the case that the commander does everything. The commander just spots the target and instructs the gunner. The reason why there is only one IR sight on the Leopard 1 are simple: 1. Unlike all other tanks of the era, the Leopard 1's gunner's sight was integrated into the rangefinder, making it impossible to directly integrate an IR sight into it. Therefore the gunner could only have a small auxiallary IR sight mounted to roof at best, which wouldn't provide enough effective range to spot targets at night - or the commander would have no IR sight. 2. The commander's task is to lead the tank, so he needs an IR sight. For the German army, mounting a short-ranged night vision system as used by the Soviet tank commanders or by the OB-23-A as usedd by the commander of the AMX-30 was not considered enough. There is a difference in doctrine, which is reflected in the fact that the Leopard 1 commander was provided with an independent sight (at first TRP, later PERI R12). The Leopard 1 commander can - since the original production model - override the gunner's inputs and has fire priority. He also doesn't operate the roof-mounted MG. In other words you could say, that in the German opinion the tank commander is more of a gunner than in the opinion of tje US Army and Soviets. In the end is a question of what you want: a good long range IR sight or two less capable systems? For the Leopard 1, the combination of B 171 II sight and XSW-30-U searchlight are said in German books to have a maximum range of 1,200 to 1,500 metres. That is a big difference compared to the M60's 1,000 metres and the TPN-1's 600-800 metres. The PzB 200 and similar LLTV systems were the first optics that actually made it possible to fire at night withotu exposing yourself (or another tank of your company) to the enemy while aiming... and it actually outranged all Soviet IR systems. The M60A1 has worse cross-country mobility given its weaker engine, lower suspension performance and greater weight. It also didn't have the best armor in the world, the Chieftain was the best protected tank at the time: it had a larger protected frontal arc: 45° instead of 30° ( ± 15°) from the turret centerline, a lower profile and thicker armor. The M60 btw. is far from immune to 100 mm APHE round (I don't even think we need to talk about 100 mm APDS and APFSDS rounds...): The M60 is vulnerable to 100 mm AP at ranges similar to the Leopard 1, if you take into account the whole frontal 60° arc. The M60A1 is still more vulnerable than the early Leopard 2(K/PT), but probably about as good - maybe a bit better - armored than the Leopard 1A3, 1A4 and 1A1A1 on the turret. The real difference in armor protection is the hull, which isn't particular likely to be hit.
  4. Oh... sorry for the mistake. This photo was posted on a German forum labeled as 105 mm DM53. Sorry for the stupid mistake, I should fact check their claims next time.
  5. I am innocent, S. Zaloga used the false form in "M1 Abrams vs T-72 Ural".
  6. Based on the graphs you posted earlier, the 120 mm DM13 and 120 mm DM23 APFSDS have rather short penetrators, but also a rather large diameter. This is relevant, since penetration increases with diameter for a given length (more accelerated mass = more kinetic energy; penetration scales with kinetic energy). A slightly thinner rod with greater length would overall be superior, but technology and/or other requirements resulted in a diameter of 32 mm for the DM23 APFSDS (thinner tungsten rod with the available alloys did shatter too often). The velocity of the DM23 after traveling 2,000 m is 1,529 m/s according to Swiss firing tables, but these list the muzzle velocity at only 1,640 m/s. So either the DM23 has a muzzle velocity of 1,640 m/s rather than the usually reported 1,650 m/s or the differences are caused by the Swiss measuring methology or are result of a local modification to the 12 cm PzKan 87 (Swiss designation for the DM23). If the latter cases are true, the impact velocity should be ~1,539 m/s instead. Given that the penetration efficiency of shorter, thicker rods is more, it seems that the DM23 might achieve a penetration per length of above 1 against German HzB A steel: (from Anderson and Riegel III, 28th International Symposium on Ballistics, "Estimate of penetration/perforation performance based on semi-infinite penetration data") The problem is that exact informations regarding the specific steel alloy are rather scarce. HzB. A (and other steels of the HzB classification) existed in several versions with different alloys and hardness levels. In so far it is hard to convert the exact penetration data into RHA penetration. For the graph from the previous post, the steel hardness was said to be 255 on the Brinell scale. Based on the plotted data, the DM23 might achieve between ~ up to 1.05 P/L, so its 360 mm long penetrator would result in a penetration of 378 mm into semi-infinite HzB. A steel. I don't have access to the source from which the data is taken (research paper by Hohler and Stilp, who apparently work for the German Fraunhofer institute), so it is unknown to me wether the steel target was sloped or not. The penetration against sloped targets would be higher than unsloped ones. As this is semi-infinite penetration, the perforation should be higher (meaning: DM23 would probably punch a hole through a 390 mm thick HzB. A steel plate under the same conditions). As for the 120 mm DM13: It is hard to say due to its unconventional construction. The BM-42 Mango APFSDS (which seems to be the closest thing in terms of internal penetrator construction) supposedly achieves a penetration slightly greater than the combined tungsten penetrator length; it has a higher muzzle velocity, but due to the fin construction a greater V-drop (Fofanov lists V-drop of Soviet 125 mm APFSDS ammo as between 60 and 140 m/s/km; given that Mango has full calibre fins, it should be significantly more than 60 m/s/km). Maybe the steel sheat helps increasing the penetration efficiency by simulating a thicker rod/lower L/D ratio? The DM13 should have slightly above 1,500 m/s velocity at 2,000 m distance according to the US graph from the last post (probably 1,510 - 1,520 m/s). That and its shorter rod should lead to a lower penetratioon than DM23 by quite a bit... how much? I don't know. Maybe it is 320-350 mm, if the steel has any positive effect on armor penetration. Otherwise it would again be close to a P/L of 1 (if DM13 behaves like a conventional monoblock penetrator), which would lead to a penetration of only ~310-320 mm. Perforation and penetration against sloped targets might again be higher. The penetrators of both the M833 and the 120 mm DM23 APFSDS have rounded tips, which performs slightly worse than flat-tipped penetrators against sloped target (but penetration still should be higher than against unsloped ones). Source is a Rheinmetall presentation from 2002. It used to be on DTIC, but I cannot find the full presentation at the moment... maybe the link expired or it was removed... The M111 Hetz was capable of penetrating the original T-72's hull armor at very short ranges (some sources say 500-800 metres maximum). The T-72 had a glacis consisting of 80 mm steel, 105 mm stekoplastika (glass-fibre reinforced plastic) and 20 mm steel sloped at 68°. The T-72A had a different layout: 60 mm steel - 105 mm stekoplastika - 50 mm steel (this is also 10 mm more steel), which was more effective against AP(FS)DS ammo. On later models, a 16 mm thick steel plate was added to the hull, improving protection further. The late production model of the T-72A featured spaced hull armor. The M111 Hetz could never defeat the turret armor except for maybe a direct hit near the gun mount, where the armor thickness was only ~300-350 mm. The turret reaches a thickness of more than 475 mm at the well armored cheeks.
  7. South Korea plans to copy the PL-01 mockup tank...
  8. A few photos regarding the Boxer's armor: General: Note that the Boxer is - like the AMV - not protected against RPGs in its basic configuration. Additional armor packs or active protection systems have to be installed. Frontal hull armor: Upper section of the frontal hull / driver's hatch: Side armor: Additional roof armor against artillery bomblets:
  9. The chart is correct. The labeling might be a bit confusing: the T-72M1 referenced in the table is not the basic T-72M1 (i.e. Object 172M-1-E5 or Object 172M-1-E6) but rather the T-72M1M (Object 172M-1-E7), which is a T-72M1 with the more advanced NERA armor of the T-72B. Later this was export variant was superseded by the T-72S (Object 172M-1-E8) as true export model of the T-72B. At least on T-72M1M tank was operated by the Republic Guard in Iraq. Rheinmetall marketed its 105 mm smoothbore guns as capable of defeating the T-72M1M (aswell as the T-72S and T-72B), which the normal 105 mm rifled guns L7 and M68 were incapable of doing. They tried to persuade the US Army to buy smoothbore guns for the Stryker MGS among others. Due to its rarity, the existence of the T-72M1M remained unknown for some while and I haven't seen any clear data to whom exactly how many T-72M1M tanks were sold. I don't think that the "basic" belongs to the T-62 version, but rather is meant to show that this is the basic threat for which the mentioned APFSDS ammunition was adopted. The values clearly reflects the T-62M. As for the penetration achieved by the M833 APFSDS: 400 mm against steel armor at normal combat ranges is not possible. The length and velocity of the longord penetrator are not enough to achieve such levels of performance. I.e. the M833 has a 427 mm long penetrator, as you can see in the following images: The following graph taken from a declassified document shows the reduction of the velocity of several APFSDS types over ranges. As one can see, the impact velocity of the M833 APFSDS at 2,000 metres (typical combat range used to measure armor penetration) will be slightly below 1,400 m/s. The following charts shows a comparison of different methods for measuring normalized penetration (i.e. LOS penetration against a sloped target) in relation to the length of the high-density longrod penetrator of an APFSDS round. It compares two mathematical solutions (the forumula from W. Lanz & W. Odermatt aswell as a sub-module of the ALEGRA software suite) with actual measurements (the dots) which are interpolated using a polynomial fit (spline interpolation). Looking at the chart, the length and velocity of the M833 would roughly result in a factor slightly below 0.8 penetrated steel thickness per penetrator length (P/L). A value of 0.8 multiplied with 427 mm will result in an estimated armor penetration 341 mm. Keeping in mind that the graph below is calculated for tungsten rods, the DU penetrator might (based on the exact criteria) perform better; the US Army Research Laboratory (ARL) has established that there is no difference in armor perforation (punching a hole through a steel target), but a difference for armor penetration (punching a hole into a steel target without fully perforating it) - so it isn't really clear wether this matters. Earlier work from ARL suggested a 8-10% lower penetration for tungsten rods, which would suggest 360-370 mm penetration (or rather 180-190 mm sloped at 60°) at 2,000 m distance.
  10. Rheinmetall's 25 x 137 mm PMB 090 APFSDS with tungsten penetrator defeats 35 mm steel sloped at 60° at a range of 1,000 m, although older documents from Oerlikon list the same penetration at 1,200 m distance (probably a result of different penetration criteria). The 25 mm APFSDS from GD should achieve a very similar penetration, maybe a tiny bit lower due to its (negibly) lower velocity (5 m/s) and shorter penetrator.
  11. The Vilkas (Lithuanian Boxer) is fitted with the Samson Mk II RWS for two reasons, which aren't true for Australia. First of all, it seems that the marketing campaign for the Boxer to Lithuania was handled by KMW. AFAIK KMW and Rheinmetall are following a system similar to how the Eurofighter is sold to foreign countries (sometimes one company takes over all responsibilities for deal, sometimes another is responsible). Lithuania never tested the Boxer with the Lance turret, but rather tested the more expensive variant with the Puma's turret. The second (and more important) difference between the two countries is the fact that Lithuania couldn't afford the original offer. They would have chosen another vehicle, if the Samson Mk II RWS wasn't adopted for cost-cutting measures. Australia on the other hand has the money and already signed a contract with Rheinmetall... You are making this too simple. In reality the contract probably includes clauses that prevent both sides from canceling it without having to pay a huge sum of compenstations. Then there is the political backlash (i.e. Rheinmetall not building the announced factory in Australia, local politicians and MPs would be pissed). Rheinmetall is not only delivering the Lance turret, but the whole Boxer and hundreds of trucks (incl. some which are already in service). There is much more on stake than just having to find a new supplier for turrets or even for wheeled 8x8 combat vehicles. Last but not least, Australia would become an unreliable customer for all members of the arms industry. You don't cancel a billion dollar deal over something simple as turrets (specifically if there isn't even an official requirement for phase 3 contenders to use the Lance turret) without loosing all your credibility. Why would any arms manufacturer make any contracts with Australia, if there was a chance that Australia cancels the deal after a contract has been signed, because they change the requirements/agreements afterwards? If you were BAE Systems & Patria, you'd abuse the fact that there would be no competition after the Boxer CRV is canceled. Just ask for twice or three times as much for the AMV-35 in such a case (something like this happened in India, where the Russian supplier - after the 125 mm APFSDS deal with IMI was scrapped due to anti-corruption laws - decided to ask for a hefty markup to sell BM-42 Mango rounds to India). Lance is modular. Integrating an APS should be really easy; however they also could opt for a hull-mounted APS. Remember that everything on the Lance turret except the basic structure with the operators' station is contained in various add-on parts. Just put the APS in such an add-on part and you're done with adding an APS to Lance.
  12. Austrian General Robert Brieger announced that the current configuration of the Leopard 2 (the Leopard 2A4Ö) can ot be supported (supplied with spare parts) anymore in the (near) future. Therefore Austria has to upgrade or scrap the Leopard 2A4 fleet, the latter seems to be unlikely. Last year Austria reactived 16 Leopard 2A4Ö tanks (bringing the active fleet from 40 to 56), which originally were meant to be cannibalized for spare parts. https://twitter.com/Bundesheerbauer/status/1024014240032714752
  13. Recon has to be light, but LAND 400 phase 2 was not the Reconnaissance Vehicle, but a Combat Reconnaissance Vehicle. The Boxer CRV replaces the ASLAV, which is also not a recon vehicle.
  14. https://www.janes.com/article/82106/poland-to-upgrade-14-more-leopard-2a4s-to-leopard-2pl-standard
  15. Puma is too small... (in German): http://www.deutschesheer.de/portal/a/heer/start/aktuell/nachrichten/jahr2018/august2018/!ut/p/z1/hY9PC4JAEMW_kbP-t-NKJBJaaFnuJRZdbMN2ZdmkQx--XQJv0hwezHszv2GAwBWIoDMfqOZS0NH0LYlu0SbIM69GReadMcJNddo3RelmhwAauPwbISZGK4UR1D2D1jDidYYPNRAgPXM6KZi2qpnQ3OigqJbKmaTSo01eSpnE4T20yN2mKFxOuZ_UT3AcBUG0zdPKAh90pu9ll3b2aWjvVPQjO8oO_4zpuUvKMhy-m8qbQg!!/dz/d5/L2dBISEvZ0FBIS9nQSEh/#Z7_694IG2S0MG2UA0AVRTKVMN1GO3 Depending on seat location, the height limit for soldiers in the Puma is either 1.91 metres (equal to somehwere between 90-95 percentil of the height of a German man) or 1.84 metres (equal to only ~75 percentil of the height of a German man). This design decision was originally accepted in 2003, because not caring much about taller soldiers allowed to increase the level of protection for a given weight. In 2013 the German army requested to change the Puma's design to incorporate taller soldiers (probably because the end of conscription lead to a smaller pool of soldiers being available). Before 2013 the army didn't asked for the changes, because investigating the internal ergonomics (which limit the soldiers' height) was only seen as reasonable on vehicles close to the series production configuration. Apparently the decoupled seats and other security related factors are main factors limiting the maximum soldier height in the Puma's rear compartment, so improvements to them could allow taller soldiers to fit into the specified height range.
  16. A few more photos. I didn't know that the armored vehicle restoration group of the German tank museum has its own facebook page. The tank is in driving condition.
  17. Maybe it's the processing unit? Other APS also make use of only a single central computer system to deal with multiple launchers and sensors.
  18. About Trophy on the Merkava IV (via otvaga forum): Note that the APS does indeed replace some of the side armor (which can be seen in the lack of bolts required to hold the NERA panels and also the hatch that is visible at the bottom). On the armor modules, there are normally lots of small bolts in that location: I guess that explains to some extend why Trophy on the M1 Abrams seems to be so much larger...
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