[HN Gopher] Project Habbakuk: Britain's ice "bergship" aircraft ...
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       Project Habbakuk: Britain's ice "bergship" aircraft carrier project
       (2017)
        
       Author : not_a_boat
       Score  : 102 points
       Date   : 2024-04-29 15:35 UTC (7 hours ago)
        
 (HTM) web link (99percentinvisible.org)
 (TXT) w3m dump (99percentinvisible.org)
        
       | akarve wrote:
       | This is one of those "so cool yet so silly" brainstorms that I'm
       | grateful someone was audacious enough to entertain. I'm both
       | relieved and saddened that it never came to fruition.
       | 
       | There's a word, chindogu, to describe things that are less than
       | useless. In some sense this project engendered more problems than
       | it solved. Like so many other attractive brainstorms.
        
       | euroderf wrote:
       | It's probably worth the trouble to try making some DIY pykrete.
       | 
       | Take a chain saw to it. Take a sledgehammer to it.
        
         | dmurray wrote:
         | Unsurprisingly, Mythbusters have tried it - not at the scale of
         | an aircraft carrier, but a boat displacing a few tons:
         | 
         | https://www.popularmechanics.com/science/a4101/4313387/
        
           | euroderf wrote:
           | "Some leaks sprang here and there, but a few sprays from
           | carbon-dioxide fire extinguishers sealed them pretty well, at
           | least for a little while."
           | 
           | Excellent!
        
         | zoeysmithe wrote:
         | Pykrete is one of those things that makes sense in theory, but
         | in practice and from a practical perspective just isn't great.
         | 
         | There aren't a lot of places in nature where you have tons of
         | trees and easy to get ice. So a society would never default to
         | pykrete because those two things tend to be the opposite of
         | each other. Its a somewhat unnatural thing to do.
         | 
         | Industrialized societies just can make steel and steel doesnt
         | start to soften until 500-600 degrees F. There's no need for a
         | 24/7 refrigerator power plant to keep steel from melting. Steel
         | also is strong and rigid. Steel is of course still used today
         | for both war and civil ships, and has been since the day it
         | became technically and economically feasible to do. Its really
         | hard to beat steel. This project has some nice technical merits
         | and pykrete itself is interesting, but it just doesnt seem to
         | ever have a practical use.
        
       | renewiltord wrote:
       | I believe they didn't actually use pykrete in the Canadian test
       | model. It was just ice.
        
       | pfdietz wrote:
       | The outcome of this project is an illustration of a rule of thumb
       | from materials science: many solid materials begin to lose their
       | mechanical properties at about half their absolute melting point.
       | This is why (for example) ordinary steel should not be used above
       | about 550 C; there's too much creep.
        
         | kjellsbells wrote:
         | Can you expand on this comment in the context of ice/water? It
         | implies ice changes behavior at about 140K, but that isnt close
         | to a phase change boundary, so what would you expect to be
         | seeing here?
        
           | SideburnsOfDoom wrote:
           | At a guess, movement like that seen in glaciers and ice
           | sheets?
        
             | pfdietz wrote:
             | That's right -- plastic deformation under stress.
        
           | denotational wrote:
           | The glass transition temperature of amorphous ice is
           | approximately 140 K.
        
         | 0x457 wrote:
         | This is that how jet fuel melted steel beams?
        
           | afterburner wrote:
           | Not melt, soften slightly
        
           | SideburnsOfDoom wrote:
           | Here's a blacksmith demonstrating this exactly:
           | https://www.youtube.com/watch?v=FzF1KySHmUA
        
         | kimixa wrote:
         | I thought the "failed" result of the project was more due to
         | economic factors, and the reduced need due to other actions in
         | the war meaning a waterborne carrier was less useful. Not some
         | issue with the mechanical properties of pykrete. If the tested
         | properties were already past that 1/2 absolute temperature
         | point and considered acceptable, it doesn't really matter what
         | the behavior would have been at less than that.
         | 
         | Did I read it wrong?
        
           | alexwasserman wrote:
           | Also what looks like insane scope creep.
           | 
           | "The full-sized ship would also need to have a range of 7,000
           | miles, support heavy bombers and be torpedo-proof. It was to
           | be over a mile in length, weigh as much as 2.2 million tons
           | and require as many as 26 electric motors to move and steer
           | across the ocean."
           | 
           | That's a crazy target growing out of "cheap to produce
           | aircraft carrier"
        
             | jamiek88 wrote:
             | Yeah it's like a mobile midway pacific war at that point!
             | 
             | Sailing midway all the way!
        
       | KineticLensman wrote:
       | Check out Hobart's Funnies [0] and the great Panjandrum [1] for
       | some other awesome WW2 British out-of-the-box thinking.
       | 
       | [0] https://en.wikipedia.org/wiki/Hobart%27s_Funnies
       | 
       | [1] https://en.wikipedia.org/wiki/Panjandrum
        
       | Theodores wrote:
       | This concept could be done today with newer materials such as
       | mylar film and polystyrene to keep the sun at bay.
       | 
       | Although a YouTuber would be able to do it for internet likes, in
       | reality, when the horse manure gets real, every aircraft carrier
       | is a dead duck when the enemy has hypersonic missiles.
        
       | office_drone wrote:
       | > they called it Project Habbakuk, in reference to ... "I am
       | working a work in your days, which ye will not believe though it
       | be told you."
       | 
       | This is a slightly more subtle way of calling it Project You
       | Ain't Gonna Believe This
        
       | FrustratedMonky wrote:
       | Think most peoples gut reaction would be that it would melt.
       | 
       | But
       | 
       | "it took three hot Canadian summers for the test vessel to
       | completely melt."
       | 
       | Seems like in north sea, it would have worked and probably would
       | have happened if it wasn't for un-related changes like airfields
       | and re-fulling planes.
        
       | msarrel wrote:
       | It was either going to be ice or concrete
       | https://warfarehistorynetwork.com/article/the-concrete-fleet...
        
         | wizzwizz4 wrote:
         | The material they used (water mixed with wood, frozen) is
         | called pykrete.
         | 
         | > Blocks of ice containing as little as four percent wood pulp
         | were weight for weight as strong as concrete; in honor of the
         | originator of the project, we called this reinforced ice
         | "pykrete". When we fired a rifle bullet into an upright block
         | of pure ice two feet square and one foot thick, the block
         | shattered; in pykrete the bullet made a little crater and was
         | embedded without doing any damage. My stock rose, but no one
         | would tell me what pykrete was needed for, except that it was
         | for Project Habakkuk.
         | 
         | (from _I Wish I 'd Made You Angry Earlier_ by Max Perutz, via
         | Wikipedia: https://en.wikipedia.org/wiki/Pykrete)
        
           | TylerE wrote:
           | Unfortunately it turned out to be basically impossible to
           | keep a ship-sized block of it frozen, and modern attempts at
           | replicating it have found the strength claims to be a bit
           | "optimistic".
        
       | FrojoS wrote:
       | This could be straight out of the Command and Conquer: Red Alert
       | series. [1]
       | https://en.wikipedia.org/wiki/Command_%26_Conquer:_Red_Alert
        
       | elwell wrote:
       | Can't get sunk by an iceberg if you are an iceberg. _taps side of
       | head_
        
       | meeks wrote:
       | What if, instead of building a full carrier out of pykrete, you
       | instead build very simple pykrete ships that follow around the
       | outside of a carrier group to add a layer of protection from
       | torpedoes and sea drones?
        
       | Yeul wrote:
       | If memory serves there was a plan to invade the Azores in WW2
       | which would have been immensely ironic.
       | 
       | After WW2 the US was gracefully handed over a few islands to
       | serve as aircraft bases. The Chinese still lack such soft power
       | so they have to make their own islands.
        
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       (page generated 2024-04-29 23:00 UTC)