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N-L-M

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N-L-M last won the day on December 13 2018

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About N-L-M

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  1. N-L-M

    Britons are in trouble

    You'd also have to make it a blowoff compartment, which requires significant cutting and welding work. Much less than a new turret would require but still not a small job.
  2. N-L-M

    The Swedish AFV Thread: Not Just Strv 103s

    Strv 2000 is entirely obsolete in the current year and would basically have to be restarted almost from scratch. Remember, Strv 2000 was a project in the late 1980s, and it's been over 30 years since then. Other than broad layout and concepts (like modular armor), and any ballistic tests conducted at the time, everything involved in that project is obsolete.
  3. N-L-M

    General AFV Thread

    Windows and firing ports yes. Probably not protected beyond STANAG III plus .50 cal fire in the frontal arc.
  4. N-L-M

    Explosive Reactive Armor

    So I was on a certain Discord server and the topic of reactive armor came up. I ended up writing a rather long post about why RHAe is a fundamentally flawed method of measuring the effectiveness of ERA, vs other models (such as a fractional model ( % reduction in penetration), even those do not entirely accurately reflect reality). I post it here unedited for your critique, do your worst (which is of course your best). Rhae The problem is that with that approach your measured "RHAe" is just a rephrasing of the measured residual penetration with no further info processing applied, and is only useful as far as your individual measurements are. And when your armor's effectiveness is affected by the projectile's penetrating ability, well, the "armor equivalency" value gets dependent on the projectiles characteristics in the specific case and not in any way in a generalized manner, which defeats the whole point of having a unit of measure in the first place. You see, nobody uses plain old 220BHN RHA any more for anything other than weapons testing. But it's still useful as a reference for armor materials within the limitations that the defeat mechanisms are similar- typically, clean penetration into semi-infinite targets. This allows you to compare different solutions within the same class. For example, if against a certain threat class 500bhn steel penetrated cleanly has a RHAe of 2 vs 220BHN steel at a given obliquity, you know this to hold true across that class and definitely for individual projectile designs. As an example, If I know that an AP round will go through 100mm 220BHN RHA at 1km, I know it will also go through 50mm of the 500 BHN stuff. Likewise, if that same projectile fired at the same velocity goes through 110mm 220 at 0.5km, at that range itll go through 55mm of the high hard stuff at the closer range. And I know that if I scale the projectile design up such that it now defeats 120mm 220, it'll also defeat 60mm 500. So far, so good. But now I try to apply the same logic to a reactive plate. A dart round rated at 100mm 220 at 0.5km is fired at the ERA and achieves only 50mm of residual penetration. From this I conclude that the ERA has a "RHAe" of 50 against this projectile design. I then proceed to fire it at 1.5km, where its penetration is only 40mm 220. By the above logic, I should expect it to never pass the ERA. But it will, and the residual penetration will shred all the poor innocent 1mm witness plates. Now lets take the same projectile and scale it up, so it can go through 120mm RHA at 0.5km and fire it at the ERA. By the above logic, I'd expect it to achieve 120mm (rated) - 50mm (ERA RHAe) =70mm. In practice, the reactive armor will chew it up such that it penetrates notably less backing as a residual effect. And for a SC example, a given single shaped charge 100mm in diameter will go through say 600mm 220 BHN at optimal standoff. A reactive layer cuts that down to 100mm. From here I get a "RHAe" of 500mm. Shaped charge penetration is known to scale linearly with size for a given design at similar non-dimensional standoffs. So we take a 0.8 scale ie, 80mm) version of the last warhead. It'll go through 480mm 220 BHN steel. Applying the equivalency logic, we'd expect the residual penetration to not exist, as the armor equivalency is greater than the rated penetration. In practice, it's going to have residual penetration, on the order of 80mm. Big error there from a difference of a mere 20% in scale. See the problem? Trying to measure RHAe for reactives is problematic because their method of operation is fundamentally different. Not only is it inconsistent within a class, it's inconsistent for a single given projectile design as well! If you want to start plotting "RHAe of Kontakt-5 vs M829A1 as a function of range" as well as the usual obliquity testing, you will very quicky find that in practice you are to within a fairly tight confidence interval merely drawing a rescaled and slightly offset ballistic chart for the M829A1 itself, which if you don't think is silly (considering you then need to do this for all known projectiles, even of similar designs), well then have fun I guess. The data you compile by this method is mostly useless at that point. Having different fitted models for different threat types and even design styles is legitimate. But when you have to individually fit each independent penetrator with a model of its own *which is also dependent on the particular state of the projectile at impact, well clearly you’re doing something wrong.
  5. https://translate.google.com/translate?sl=auto&tl=en&u=https%3A%2F%2Fwww.idf.il%2F76384%2F Israel's 6th Dolphin sub to be named Dragon and not Dakar as previously reported; the next class of submarine will be called the Dakar Class.
  6. N-L-M

    Documents for the Documents God

    http://www.dtic.mil/dtic/tr/fulltext/u2/a554529.pdf A fairly exhaustive look at the work of Prof. Dr. Manfred Held (PBUH), and the science of reactive armor initiation.
  7. That is SEPv3. Somebody must have forgotten to rename the contracts.
  8. Shit, that's around $4mil per tank upgraded. Cost of being cutting edge I guess.
  9. Because when you make a robotic vehicle you do it for one of 2 main reasons: 1. As a technical demonstrator 2. As a useful vehicle In the first case, using old tanks is silly because theyre crazy expensive to run. You can run a M113 or MT-LB if you want a tracked vehicle, or a fancy ATV if you don't, all of which are waaaay cheaper to run than a tank. For the second case, you want a useful vehicle even in the face of enemy fire. If you don't want to stop enemy AT fire, your choices are the same as the above, plus the option of a purpose built compact vehicle. If you do want to stop enemy AT fire, the old tanks aren't up to it and need at the very least to be uparmored; and by being significantly larger than they need to be (as computers are smaller than crewmembers), this ends up being significantly larger heavier and more expensive when compared to a purpose-built vehicle. In either case, the old tanks aren't really worth it.
  10. N-L-M

    Israeli AFVs

    Those are garbage bags. MGs do not like being exposed to the elements for any length of time, they get all wet and therefore rusty and all the oil runs off and shit. Wrap them in a garbage bag and duct tape it shut and you have a fairly effective quick and disposable environmental shield.
  11. N-L-M

    DRDO; India's Porsche

    That's a Sparky vid. You can tell by the distinctive spastic red and yellow text overlaid with no consideration of contrast over background images. Sparky and his opinions belong in the trash. The most powerful tank gun actually fielded on serially produced tanks was probably the US M58 120mm gun.
  12. N-L-M

    DRDO; India's Porsche

    Lmaoing@indians Stay mad with your shit tank, shit rifle and even shitter development office. Reminder that as of today another year has passed and the NAG missile STILL isn't in service.
  13. N-L-M

    Future of AFVs

    Hint- it's retardedly easy. You have a radar, which detects incoming rounds. And a shutter, which can stop them. You use the radar to cue the shutter. You can even have 2 different kinds- the shutters on the radars and optics close only during the calculated time of impact, and otherwise stay open. The shutters on the interceptors stay closed except for launch. Easy, your APS is now resistant to anything smaller than what your shutters are rated for. You could do this for 14.5mm KE if you really wanted but the servos would get a bit fat. 35mm KETF cannot compete.
  14. N-L-M

    Future of AFVs

    I disagree, it's retardedly easy to defend against light frag like the proposed system uses.
  15. N-L-M

    Future of AFVs

    And I think you're focusing on the solution and looking for a problwm it can solve. Except that with retrofit-level tech MBTs can be made entirely immune to such autocannon bursts. Fact: diverse isn't always superior. And when you're giving up internal volume to a system that is inferior in every important respect to the alternatives it displaces, that's a no-go. Weight and volume better spent on electrical systems and 130mm ammo, not superfluous coax autocannon. No, a coax MG exists to provide suppressive firepower against enemy troops whose location is not known precisely and to offer a close in self defence option with a large ammo reserve. Anything larger than "jihadyota" is "worthy" of 120/130mm MPHE. At the cost of displacing 130mm MPHE, which is a price not worth paying. The rationale is that you're basing your entire concept of effective gunfire vs an opponents MBT on your ability to first land effective hits with your autocannon. This means your effective range is limited to the effective range of said autocannon. Unless you don't think the autocannon is needed to ensure effectiveness, in which case why install it in the first place? Also, you seem to be greatly underestimating the bulk of an autocannon and associated ammo and feeding. You are displacing quite a few main gun rounds, which are significantly more effective, and consequently only harming the vehicles effectiveness. And the argument of saving rounds is a result of you completely ignoring alternative counter-APS approaches that do not involve multiple main gun shots. So you'd trade the long range firepower of stowed 130mm rounds for the ability to pepper enemy MBTs at close range with small frag which they can easily resist. After admitting that the ability to counter APS exists regardless, as you use it at longer ranges. Yeah no. What I'm saying is that the line infantryman shouldn't be packing a pistol and 9mm ammo in the first place, but an equivalent weight in 5.56mm ammo, because 9mm is low energy, sad, short ranged and innaccurate and won't go through the enemy's body armor. Particularly not when the metaphor breaks down, as tech has been pushing the effective engagement ranges ever further out, so why the hell would I take a 9mm when I intend to fight the enemy at 800m? No it isn't. There are options that do not require sticking around after announcing your presence like that. What is leading the target Who let the target get within 3km Confirmed for not understanding how ballistics or time work. Protip-30/35mm fullbore rounds take a lot longer to reach 3km because the MV is low and the shells lose velocity quickly. And all this extra time is time for the target to disappear and time you leave yourself exposed after announcing your presence, which is just asking to get nailed by someone who doesnt waste their time with autocannon bursts. Better but still not as good as just not bothering with the small caliber shit in the first place. For a start as Bronez pointed out that solution is very sensitive to so many environmental conditions that its a non starter. Again, the alternative does not have to be firing multiple rounds from the main gun. But even if we assume for a moment that it is, well then you'd design your gun and autoloader for that purpose. And pre-selected ammo flick rammed 120mm guns can reach 120rpm. It's been done. Much faster than waiting for slow autocannon shells to cross the distance. The point of such shutters is that you close them for a very short amount of time to protect the soft portions from frag and then open them again. They dont have to be closed for any longer than 0.1 sec per fragmentation round sent the way of the protected vehicle. Servomechanisms powerful enough to move STANAG 3 level shutters at high velocity are established tech. Really fucking fast. Its a matter of how fast you want them to move, and building an appropriate servo mechanism. Servos are insanely fast. And yes these shutters could also protect the system from small arms fire. Protective covers are not shutters. If you need to manually remove them before action they aren't the kind of system I'm talking about. Shutters as their name implies *shut*. Watch the vid LooSeR linked. Yes, because you can carry 10k linked rounds for a machine gun as 7.62 rounds are tiny and because you want an emergency backup weapon that can prevent you from getting overrun by squishies and practically speaking eint run out of ammo. The MG is not however considered a primary weapon system substitute for any target. No. 120 or 130mm MPHE shits all over 35mm HEAB against all squishy targets. And to top it off the multiple smart fuzes on the multiple HEAB rounds you need to send downrange to provide a similar effect means the autocannon option is more expensive. And thats without getting into how at long ranges the 35mm just cant reack and suffers such poor dispersion that significantly more rounds are required. 35mm cannot compete in the big league with the big boys. M. P. H. E. If you dont want to bring down the building you set it to SQ or PROX. Will bring down part of the wall and anyone behind it but not the building. If you want the building to come down you use PDD. You don't need autocannon rounds for this. There are many upsides too. Most of them involve the multipurpose selectable destructive effect of MPHE rounds. And you're going to have autocannon equipped IFVs around anyway, in case you happen to run into a contrived situation which somehow only an autocannon can solve but a 120mm MPHE can't (or that a RCWS with a 40mm AGL with high elevation also won't solve). Still not a reason to install a coax autocannon on a tank. 100% of released future concept "tanks" with autocannon have no main gun to cut down weight and save cost, not because it provides complemetary firepower on the same platform. I like the way you ignored all the other targets I listed. But just to make the point clear- the autocannon does not provide any additional AP capability against them either, as they will be immune. So again it is redundant. This is just grasping at straws. 130mm ammo vs 120mm ammo requiring lengthened racks 'may cause problems' despite such work having already been done for the old 140mm systems? Last time I checked most countries are satisfied with current ammo capacites. And the shrinking of crews as you point out frees up volume, so what prevents you utilizing that volume for effective useful 130mm ammo? There were a few already mentioned in this thread, had you bothered to read it. The additional length and greatly increased muzzle energy of the 130mm give a lot of room to play around with while keeping a reference long rod going at the desired velocity. Decoy darts, segmented programmable rods that break apart before entering the APS intercept zone, RCS reduction of the dart (and matching of any decoys), EW methods, AHEAD-tipped darts to try and hit the APS munition itself first, and many others. All of these are more future proof than trying to spray the opponent with light frag, and none of them require the entire vehicle to be designed around them. So again, in conclusion, you're obsessed with this solution and are desperately looking for a problem to justify it despite it objectively being a poor one.
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