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TokyoMorose

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Everything posted by TokyoMorose

  1. I fully understand, but if you get immobilized and blinded by HMG or light autocannon fire, the crew capsule is now a stationary and defenseless target for whatever heavier weapons the opposition feels to use at their leisure.
  2. The Jaguar really causes some mixed feelings for me, because while I understand it is not made to stand up to AT fire (and that would indeed be a silly requirement) there's so much exposed that seems vulnerable to ubiquitous HMGs and light autocannons - lots of what are presumably hydrualic put possibly pneumatic lines on the undercarriage *entirely unprotected*, and all sorts of electronics and sensors on the upper works. Even the armored shutters for some of them don't appear to stand any chance of stopping HMG fire closed up, they seem to be just a few mm thick. Just makes me nervous that a well-camouflaged KPV or DShK/KORD would have no issue effectively disabling the thing, even if I am sure the actual fighting compartment is protected. And if those unprotected lines on the undercarriage are hydraulics, then running over a landmine on that will be a truly enlightening experience.
  3. There has already been a CAMD report linked, translated handily by Samsonov, listing both the V-2 in the T-34 and the 6046 in the M4A2 as having ~200 hours (the numbers are slightly different but well within a reasonable margin of error of a few hours) average lifespan. That was from the second guards' tank army in 1945. Your points on the other Shermans having various models of engines is of course valid, as is the various T-34 derivatives. But the posts you were replying to for the R-975 post were discussing the M4A2 for comparison's sake (it's the easiest statistical comparison to T-34s as it was operated by armies who operated enough T-34s to get good average data) and just stuck out in my mind as being very irrelevant.
  4. I hate to barge in with a late reply, and this is a side point - but why would the poor lifespan of the R-975 have any relevancy in a discussion comparing to the GM 6046 on the M4A2? All of the other sources earlier posted comparing T-34 engine life to Sherman engine life were using the 6046-equipped M4A2 as that is what the Soviets had.
  5. I was tempted to mount ye old M135 demolition cannon as a secondary mount to meet the HE requirement while being under armor. I am quite certain the 165mm HEP round would satisfy even the most ardent of rangers.
  6. Doing some numbers in my head and comparing to various guns out there, if that 7.5lbs HE per shot or salvo requirement is in terms of fill weight and not total shell weight (and I am assuming that is the case)... meeting that is going to be an interesting challenge. Some of the ideas I have are real goofy for that.
  7. What is *doubly* weird is that the Chinese gun internals are hard-chromed. The 2A46 family did not introduce that until the 2A46M - so the Chinese made the effort to modify production tooling and procedures to allow a good chroming, but didn't also copy the rather simple front-change screw mechanism that is very well known? Really is a baffling combination of gun "features".
  8. This seems to be such a terrible idea, having a bespoke chassis and systems defeats the logistical and cost reasons of using a technical (y'know being cheap and with parts available on the market anywhere) while also intentionally limiting performance compared to purpose-built buggies like the flyer. You simply can't fit a bodykit that looks reasonably like a regular civilian vehicle on one of those buggies, otherwise they'd just do that instead of asking for a new vehicle that can look like that.
  9. BD's comments from Coffman are relevant "That said, Coffman added, if a company comes in with a 30mm weapon, “they have to show us a path to 50.” " Again, the 50mm is effectively mandatory - and given the way the army works they are going to prefer the XM913 they have already paid to design and proof over the WOTAN gun to the point the XM913 may as well be considered mandatory. Same deal with the turret, on paper you could offer a different gun and turret but Army brass already have those programs deep under way. It's like the M4 replacement contests where you didn't *have* to submit a 5.56mm gun, but it'd be stupid to think the Army wouldn't choose their existing solution. I am not saying that I expect the armor levels to be identical to GCV, I am saying that the margin of armor level scale-back from that was not big enough to make the tens-of-tons difference needed to make things work. Clearly the Griffin III was not based on terribly detailed knowledge as *GD never even attempted to bid it*. I take the Griffin III to be more of GDLS demonstrating what they can have ready in the short term with existing components or components already in development. It was not aimed at the OMFV requirement or GD would not have bid a totally clean-sheet solution. The Army does not have to be dumb as a whole to write a totally dumb specification. The DoD has done this many times before. And again, I never said the Puma would meet the US's requirements. I am saying it is the *closest* to meeting the requirements. There is in fact no IFV in the world that meets their requirements which is why they had to restart. They could always try to restart their efforts to Americanize the Puma that they had going with SAIC years ago... (and for full pedantry, the American Harrier II is very similar to the UK Harrier IIs, but I do get the fact that the Harrier II vs Harrier Is is pretty much totally different planes) Come on Ram, Zumwalt was loaded down with so many "transformational" ideas that most of them had to be cut out to fit the budget (composite deckhouse, AN/SPY-4, pretty much all of the flush-mounted electronics that are now replaced with scabbed-on systems) and suffers crew fatigue from the 'transformational' manning scheme. And you could write entire novels on how the LCS has failed to deliver on its promises.
  10. Unless my memory serves me wrong, doesn't the Army designed 50mm turret have independent sights? That would mean a three man crew is essentially mandatory, as the 50mm is effectively mandatory (all 30mm entries *have* to demonstrate a path to the 50mm, and the Army is going to want its turret used). You do save on three dismounts, but you're only going to save so much weight there (I.e. comparing to GCV you would need to knock more than 10 tons off, or >20% of total vehicle weight just by removing three dismounts - I remain doubtful that the dismount reduction allows that level of savings). I use the GCV for comparison because it is the closest requirement that matches the OMFV reqs, and because it was designed with essentially the exact same technology/industry base. As to the Puma, as much as I genuinely believe that would have been the most satisfactory solution, the Army disputed CBO's reckoning about the Puma's survivability (they are likely using different matrixes for calculating scores) and it needed more equipment added on to meet specs anyhow (particularly now with the 50mm). Griffin III was never bid, and simply does not have the protection to meet the requirements or GD would have bid it. Honestly, Griffin III is just a tarted up system almost as old as the Bradley (good ole ASCOD). Transformational change is how they got LCS, Zumwalt, and EFV or did they memory hole that?
  11. What we know about the protection requirement in the public sphere is that it was very high, both from industry source comments and the fact that their last IFV program just a few years ago fell apart along almost identical lines do to a combined protection rating that was absurd. They may have scaled back since the GCV slightly, but it would seem not too much. The GCV requirement specified better overall protection than even the then-current SEPv2 Abrams, and over a full 360 degree arc according to their graphs given out late in the program. 52 isn't *that* much larger, raytheon/rheinmetall may well have invested in efforts to try to shave weight off here and there if they felt they were only 2t away from meeting the threshold protection and weight requirements - but they didn't, they consciously decided not to bid at all - like everyone else but GDLS. After all if they win by default on a multibillion dollar contract, even the costs of redesigning things to scrape out every last gram of weight are worth it. (Such as replacing steel interior fittings with titanium - a very expensive option but one of those 'we gotta kill weight at any cost' things) I mean, I didn't say the skeletonized hull was a foolproof surefire success (it reminds me of some of the more crackpot aspects of FCS all too well) - it just seemed to be the only way to cut the gordian knot of the contradictory requirements. The army may well have liked growth margin, but if the only vehicle that meets requirements has low margins and the competition is held under normal rules, it wins by default. Now if there was a mandatory growth margin tonnage or percentage in the detailed sections of the requirements that's a different story but only making the weight requirement even more hopeless (as the margin means an inherently heavier hull with overbuilt mechanicals as I'm sure you know). Timing sort of ended up as an excuse as that was the official reason given both by the DoD to the public and to other government groups when they were questioned for going ahead sole-source, and the official reason given by Rheinmetall when they were asked as a corporation; I fully understand the reason for the shipping failure was a conscious decision not to bid weeks beforehand but as far as the award decision stated Raytheon/Rheinmetall were officially DQ'd for failure to ship test articles, not failure to bid.
  12. That's kind of my point, Raytheon-Rheinmetall decided not to bid and the shipping issue was merely a side effect of a conscious decision to not bid. They decided not to bid because they knew they couldn't meet the impossible requirements, and Lynx can already grow to the ~50t number that NLM posits for the GD bid. Hence my supposition of the actual amount of weight needed to meet the requirement being much larger. Supposedly, their tender was all-new. And considering their heaviest existing chassis cannot get anywhere *near* the required protection given its relatively low weight cap (42t) I am tempted to believe that.
  13. Because I cannot honestly see how an IFV in the ~52t range meets the very demanding passive armor requirements. Otherwise there was nothing stopping Rheinmetall from just offering a heavier bolt-on kit for the Lynx (which Rhm states has 6t of growth capacity at its full 44t weight), and Rheinmetall made no effort in that direction at all. Instead they just quietly dropped out under shipping errors as an excuse. I find it quite likely that GD went for a radically pared-down base vehicle with virtually all of the armor being bolt-ons, and comments from industry suggest that the passive armor weight fraction is indeed very high, beyond what is normal due to the 360 degree protection requirements. I find it also telling that breaking defense said that GD's proposal was to ship the armor kits separately in other C-17s (which is implying an armor kit more than your 13t hypothesis as that would happily fly on a C-130, which they *would* have touted as there are a *lot* of C-130s and that was even a firm requirement back in the FCS days). I cannot say for certain obviously, but all of the info points more to a 40-50% passive armor fraction and virtually all of that being bolt-on. (And yes, vehicles with such high armor fractions *have* been built before, it's not impossible). IMHO if modular armor was really capable of meeting the requirements at the weights you posit Lynx simply would have been entered with a heavier add-on kit, especially since Rheinmetall has its fingers deep in the manufacture and sales of modular armor kits.
  14. Ah yes, as opposed to rolling around in the less-armored current Bradley and getting troops killed. Furthermore, does this not allow us to basically guesstimate the full-up weight? It seems to be within a few tons of the infamous 84 ton BAE GCV IFV maximum weight. It seems the army just reused the nonsense requirement wholesale from GCV...
  15. Hey, I guessed right - the absolutely stupid 360 degree protection requirement was what doomed the GCV as well (remember the baseline config was 60 something tons and the system max was 84?). The Puma is as good as you can get protection wise and fitting two on a C-17.
  16. That's just the contract legalese, actual vehicle requirements are tab 2 of attachment 0045, which I have not found.
  17. I would bet money if I had it, that the requirements list was in the recent DoD tradition; being simply absurd and couldn't be met reasonably - and everything else is saving face for that. You don't end up with a sole offer on a program of that size, unless you are demanding something goofy. Nobody even bothered (sure, the Lynx technically couldn't be shipped in time - but failure to ship in time is something that reeks of the bosses not treating it as a plausible thing) to bid outside of GDLS, and if Breaking Defense is right, GDLS couldn't even actually meet the monstrous spec list.
  18. Thanks for the answer, I was well aware of the use of the KMW chassis on the Mark 7s and the CR2's warmed over CR1 design - I just never really figured out why they totally abandoned the aluminum hull. Wonder if they could have ever solved the wear issue.
  19. The decision to use an aluminum hull is also quite brave, the thing is only 47t despite mounting much of the same mechanical components as CR1/CR2 (and the whole universal turret assembly which was the forebear to the CR2 turret). Considering that it was the NERA modules that provided the real protection, I do wonder why Vickers totally ditched their hull design and opted for others. It is exceedingly unlikely this is carrying 20t less armor than the CR2, so this seems to be mechanically a better hull.
  20. In general, no - but a lot of the detailed ideas still remain extremely wonky, such as purposefully forgoing armor in total reliance for active protection. Even if you build an all-conquering APS, it'll still quickly deplete its loaded bank of shots. There's also a *lot* of as-yet unworkable electronics demanded, and they even considered stuff like exoskeletons. There was also a planning undercurrent behind all of the FCS designs that high-intensity peer conflict was a thing of the past. The general concepts they were working on are indeed workable now, but without your all-conquering APS and literally magic electronics & sensors they aren't nearly as viable - FCS was only viable on paper *because* of the all-conquering APS & absolute omnipresent networking & data fusion along with nearly omnipotent sensor systems. Even the latest sensors and networks are far below what FCS was aiming for. (As an aside, FCS *was* laughably pie-in-the-sky technologically in the context of when it was approved! It'd be like trying to put the current top-line smartphones with everything they have into service in the mid 2000s, sure it's not seen as a big deal now but the Army were really "optimistic" with approving that program...) There's some tested systems I seem to remember seeing that do alright against KE (I forget the names), although none fielded that I know of. The Quick Kill system proposed for FCS was extremely wonky, never fully worked right (although has some real impressive looking test footage!), and to this day still isn't fieldable. And then you get to the issue that the QC VLS cells were in packs of 4-8, and I've only ever seen one or two packs on the FCS vehicle renders. I've also never seen anything resembling a quick reload method for the QC, and so if worst case scenario you have only 4 of them loaded and the enemy takes 5 shots at you with an old T-12 Rapira... then what? Honestly not being able to rapidly reload is a total killer for an APS outside of Low Intensity patrols, and Quick Kill's design doesn't appear to be fast to load and certainly cannot be reloaded under armor.
  21. So with FCS being too sci-fi, the army is repeating the mistake of the 84-ton GCV monster now in going maximum conventional. Do they not have a setting between 'pie in the sky tech dream' and '50 year old tech'? Reminds me of the fact we have both the B-2 & B-52 in service...
  22. This is going to be a guess here, but I'd say the most likely reason is transmission cooling. The X-1100 is capable of 1500hp with Abrams-level engine bay cooling but the Patton simply doesn't have as much cooling capacity. The engine/transmission powerpack is most likely being limited due to the combined limits of ventilation in the patton hull. That's very true, but the C32 is very different in form to the AVDS as well. The C32 choice just baffles me.
  23. I would argue it was finished, the GDLS brochure linked by Sovngard stated that the pre-production engine fully completed testing and verification, and offered the engine for sale for refit immediately. No mention in the pitch of any future work needed. I'd also argue it's important that L3 has kept the engine listed for sale even after several website total redesigns (in other words, it wasn't just carried over from back when the pitch was first being made) - and given that L3 has the MTU883 license it would make little sense for them to still (barebones, admittedly) market it if unfinished. The 883 is better in every way. I do not doubt the quality of the C32 ACERT, the HP rating chosen isn't even the highest rating so it'll run forever. But I don't recall the Israelis having too many issues with their AVDS-1790-9ARs of a very similar power rating, it seems to be the 1500HP variant detuned to the same 1350HP (which seems to be chosen for a reason perhaps gearing wise, as the C32 ACERT is listed as up to 1800hp in hottest, shortest-use tuning) would have no issues at all.
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