gradenko_2000 posted:How far of a distance could you cover at hypersonic speeds if you "only" had five minutes to do it I think not very far 300+ miles Basic Poster has issued a correction as of 05:36 on May 8, 2023 |
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# ? May 8, 2023 05:29 |
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# ? May 24, 2024 16:53 |
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only go hyper sonic at the end.
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# ? May 8, 2023 05:46 |
death from above bitches https://twitter.com/dafengcao/status/1043036417843056641 fear the balloon
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# ? May 8, 2023 05:51 |
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Cuttlefush posted:... is this a trick question about non-dimensional mach number or parabolic trajectories and ground distance or something? no, it wasn't. I was reacting to the post saying that hypersonic missiles needed to withstand re-entry-level temps for "tens of minutes", so I was trying to get perspective on how far you could go if you didn't have that. but thank you for the responses
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# ? May 8, 2023 06:08 |
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gradenko_2000 posted:no, it wasn't. I was reacting to the post saying that hypersonic missiles needed to withstand re-entry-level temps for "tens of minutes", so I was trying to get perspective on how far you could go if you didn't have that. ah, yeah. no it's more that if you're going at hypersonic speed you're subjecting parts of your missile to re-entry level temps, i believe. from reading some papers on design/testing the issues weren't actually re-entry, it was actually sustaining hypersonic speeds in a scramjet. iirc it wasn't really comparable to re-entry in the sense that you have to "survive" re-entry temps and can just use a heatshield. it was more like shocks develop at certain temp/pressure regimes that rip apart part of the scramjet or that some temperature/pressure regime just does not work for thrust with some configuration. that's mostly stuff that has cropped up and been solved repeatedly in normal jet engine designs. I'll dig through my posts here because I'm pretty sure I posted someting addressing exactly that. also I recall one of the more immediate problems was they there were too few or no require wind tunnels to actually design things in the right regimes. so it's not really a materials science problem in the sense that re-entry shielding is. it's more like trying to make sure you can turn the re-entry plasma air into the right temp/pressure of air for the engine to keep working properly, and to do that over a very wide range of temps/pressure of incoming air. and also to deal with all the kinds of shocks that can occur or weird little aerodynamical edge effects that can get ignored at mach 2 but can melt the leading edge of anything at mach 7 because they're a little thin film of superhot compressed air
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# ? May 8, 2023 06:39 |
Delta-Wye posted:death from above bitches Lol they are going to build rods from god
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# ? May 8, 2023 06:45 |
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gradenko_2000 posted:no, it wasn't. I was reacting to the post saying that hypersonic missiles needed to withstand re-entry-level temps for "tens of minutes", so I was trying to get perspective on how far you could go if you didn't have that. I made a few posts about this not too far back in the thread but they dont seem super coherent. https://secwww.jhuapl.edu/techdigest/content/techdigest/pdf/V18-N02/18-02-Waltrup.pdf is a pretty brief history of early development that doesn't really go into technical detail but shows what the historical hurdles were, how they got solved, and where things ended. that's from 1997 but i think development kinda stayed there until a few years ago-ish. https://crsreports.congress.gov/product/pdf/R/R45811/35 is a a congressional research service report i posted before and it's a bit cooked but it seems pretty useful for the actual state of things now and what challenges are. or at least what us politicians might think those are. honestly the issues for congress portion of that is interesting and tells a lot of the story. also the emphasis on not having the right kind of wind tunnel for testing/design. basically it sounds like there's no big technological hurdle at play here that russia and china solved that the US can't. pretty sure it has something to do with how comparatively advanced the US progression into neoliberalism is and how the quarterly event horizon prevents any planning from escaping into the future. basically i think lockmart et al realized that Star Citizen has the most profitable business model possible and they are doing that and making up various names for potential hypersonic missile projects and powerpoints but nobody will build a wind tunnel. (that's not true because tehre is live testing, but it seems kinda truthy)
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# ? May 8, 2023 07:09 |
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https://twitter.com/anders_aslund/status/1655218769583566848 the woke general that everyone hated? is gone, does that change anything
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# ? May 8, 2023 07:14 |
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Delta-Wye posted:death from above bitches Should have saved this test for Blinken's China visit.
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# ? May 8, 2023 10:52 |
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Looks like the Navy is starting on their new frigates. I wonder what hilarious shortfall these will have after the various LCSCODChimera posted:https://twitter.com/anders_aslund/status/1655218769583566848 Surely eliminating any contradictory voices on the war will lead to success
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# ? May 8, 2023 13:26 |
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KomradeX posted:Looks like the Navy is starting on their new frigates. I wonder what hilarious shortfall these will have after the various LCS Biden is surrounding himself with yes men and members of his own political faction obviously.
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# ? May 8, 2023 14:22 |
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GlassEye-Boy posted:Biden is surrounding himself with yes men and members of his own political faction obviously. Surely the sign of a successful war
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# ? May 8, 2023 14:27 |
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KomradeX posted:Looks like the Navy is starting on their new frigates. I wonder what hilarious shortfall these will have after the various LCS How loving hard is it to do OHP II, with modern sensors? There are great warship designs from the 60's that basically would only need new sensors and more modern power plants fitted and would be great.
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# ? May 8, 2023 14:46 |
Frosted Flake posted:How loving hard is it to do OHP II, with modern sensors? Not costly enough
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# ? May 8, 2023 14:50 |
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Frosted Flake posted:How loving hard is it to do OHP II, with modern sensors? lame bring back the California-class all nuclear navy
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# ? May 8, 2023 15:13 |
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The Constellation is a actually just an existing Italian/French frigate, it isn’t anything wild. They only buying a limited run of them though and it is unclear how they are going to come out from the shipyard. More recently Fincantieri’s CNC machines and network was hacked but they said it wasn’t a big deal.
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# ? May 8, 2023 15:24 |
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Frosted Flake posted:X-posting
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# ? May 8, 2023 15:29 |
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Frosted Flake posted:How loving hard is it to do OHP II, with modern sensors? “new sensors and a modern power plant with distribution to match” is itself expensive. Though after the dumpsterfire LCS, the FFG(X) is using a proven design as the base ship itself instead of a novel design.
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# ? May 8, 2023 15:30 |
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i think the us surface navy is just absolutely hosed at the moment at most levels and they're gonna gently caress up any ship they can procure. you don't end up with something like the freedom and independence by accident. they will be able to gently caress up whatever the new frigates end up actually being in the end. or if all else fails, crash them into other ships. surface fleet is all hosed up
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# ? May 8, 2023 16:18 |
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Chinese surface fleet building makes US surface fleet building look like Russian surface fleet building
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# ? May 8, 2023 16:19 |
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KomradeX posted:Looks like the Navy is starting on their new frigates. I wonder what hilarious shortfall these will have after the various LCS which shipyard are they being built at? that was a big part of the LCS.
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# ? May 8, 2023 16:21 |
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i think the russian stuff actually worked when it was turned on though
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# ? May 8, 2023 16:21 |
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Bar Ran Dun posted:which shipyard are they being built at? https://en.wikipedia.org/wiki/Fincantieri_Marinette_Marine?useskin=vector not sure if they're building any of them elsewhere
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# ? May 8, 2023 16:22 |
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the trimiran one was designed from https://www.austal.com/ships/benchijigua-express, which is a trimiran fast ferry. same dimensions pretty much. it seems pretty reliable for a fast ferry but also it seems to have similar propulsion issues. i think the lack of sacrificial anodes and other hosed up hull problems might be unique though (or were those the non-trimiran design?)
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# ? May 8, 2023 16:26 |
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Just copy the type 055, easy.
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# ? May 8, 2023 16:57 |
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French frigates, malafon for everyone.
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# ? May 8, 2023 17:01 |
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Cuttlefush posted:https://en.wikipedia.org/wiki/Fincantieri_Marinette_Marine?useskin=vector oof looks like they made the same mistake again. literally one of the LCS shipyards. brown water US tug yard being managed by an Italian cruise ship maker. lol they’re going to gently caress up again.
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# ? May 8, 2023 17:06 |
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It's going to be hard to surpass a ship that corrodes in seawater, but I believe in American ingenuity.
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# ? May 8, 2023 17:24 |
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I just remembered about the Zumwalts and how they planned for 30 of them ans built 2. lol all around Being succeded by another iteration of ship you replaced is funny. Especially since I remember the 90s and how this was going to be just like F-117, an unsinkable Navy
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# ? May 8, 2023 17:31 |
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KomradeX posted:I just remembered about the Zumwalts and how they planned for 30 of them ans built 2. lol all around also it was supposed to have a rail gun but they scrapped it after the ammo cost like $10 million a shot
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# ? May 8, 2023 17:40 |
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KomradeX posted:I just remembered about the Zumwalts and how they planned for 30 of them ans built 2. lol all around they couldnt even be bothered to make a high poly model for it
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# ? May 8, 2023 17:49 |
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Raskolnikov38 posted:also it was supposed to have a rail gun but they scrapped it after the ammo cost like $10 million a shot Just a mountain of lols
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# ? May 8, 2023 17:54 |
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A patriot missile is 4 mil a shot and you always shoot two. So it's about the same cost. Maybe they couldn't get the railgun to work at all?
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# ? May 8, 2023 17:57 |
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KomradeX posted:Just a mountain of lols They also forgot that seawater is good at corroding things when they designed the advanced radar-absorbing panels.
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# ? May 8, 2023 18:02 |
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KomradeX posted:I just remembered about the Zumwalts and how they planned for 30 of them ans built 2. lol all around Bath Iron Works. No wonder they were surprised by salt water.
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# ? May 8, 2023 18:02 |
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WrightOfWay posted:It's going to be hard to surpass a ship that corrodes in seawater, but I believe in American ingenuity. brown water tug / laker folks. the hulls on the Great Lakes just never corrode. there are hundred + year old ship hulls on the lakes. some of the tugs are … older. these also aren’t yards that would have had experience with galvanic corrosion on mixed metal hulls. The bigger bluewater shipyards do. it was exceptionally stupid the first time. I don’t like the brown water / blue water divide/snobbery in the US, but lol there it is. and they’re doing it again. lmao.
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# ? May 8, 2023 18:02 |
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genericnick posted:Bath Iron Works. No wonder they were surprised by salt water. now they should have known better.
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# ? May 8, 2023 18:03 |
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Just give me the money. I’ll sub it out without fuckups.
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# ? May 8, 2023 18:05 |
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Frosted Flake posted:How loving hard is it to do OHP II, with modern sensors? American naval tech going the route of American space tech, went from moon travel in the 50s to exploding unmanned flights that destroy the launchpad. America will fight WW3 with wooden boats that somehow still cost 870 million a pop.
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# ? May 8, 2023 18:13 |
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# ? May 24, 2024 16:53 |
its also fun that a single Chinese shipyard has more thru-put and capacity than all the US shipyards combined. and they have 13 ship yards total pumping out combat and support ships. i think they surpassed us in ship count and we don’t have the parties or enough private sector desire or know how to meet them. China can probably just run out the clock another year or so and walk into Taiwan.
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# ? May 8, 2023 18:29 |