All that is solid melts into air...craft carriers

March 11, 2020 10:39 AM

Project Habakuk was a World War II plan to build aircraft carriers made from a substance that, as Louis Mountbatten told Winston Churchill, was "ice that won’t melt." This "ice" was pykrete, a frozen mixture of wood pulp and water named for its inventor, Geoffrey Pyke. Testing for Project Habakuk began in mid-February 1943 at a site on Lake Patricia, just outside of Jasper, Alberta. The project was eventually scrapped, but remnants of the test work can still be found at the bottom of the lake: scuba diving the Habakuk shipwreck in Patricia Lake. In 2014, a pykrete dome was constructed in Jukka, Finland as part of a series of projects exploring the applications of structural ice. Previously: ice ice, baby.

More on Arno Pronk, who is extensively involved in present-day structural ice research:

Meet the ice doctor who’s reviving the frozen science behind Canada’s secret weapon from WWII

"Funicular Ice Architecture"

Finishing the Tower | Interview

MythBusters: Pie-crete

The Hydraulic Press Channel asks: "How Strong is Pykrete?"

posted by mandolin conspiracy (16 comments total)

I'm eyeing a pile of sawdust in the garage and the snow outside and adding "build a semi-permanent snowman" to my list.

Also previously and somewhat related - concrete ships!
posted by inflatablekiwi at 11:07 AM on March 11, 2020 [2 favorites]

I suspect Pyke only got heard because his first cousin, Magnus (aka the rueful-after-the-fact voice of “Science!” in Thomas Dolby's She Blinded Me With Science), was one of the boffins who pretty much stopped the UK from starving at the beginning of the war. Magnus Pyke's Manual of Nutrition (PDF, this ed. 1947) was a life saver.
posted by scruss at 11:33 AM on March 11, 2020 [11 favorites]

I walked around this lake, it's lovely.
posted by not_that_epiphanius at 11:43 AM on March 11, 2020 [1 favorite]

Magnus Pyke's Manual of Nutrition (PDF, this ed. 1947)...

I just read the Preface and it is amazingly applicable today.
posted by agentofselection at 11:50 AM on March 11, 2020 [1 favorite]

The Mythbusters did an Episode on Pykrete and found that it's much stronger than normal ice but it'll still melt under normal boat-like conditions.
posted by Mr.Encyclopedia at 11:58 AM on March 11, 2020 [1 favorite]

I love the story of Project Habakuk! I had no idea it left behind a shipwreck.

Pykrete’s okay, but if you really don’t want your aircraft carriers to melt, make them out of Ice-9.
posted by ejs at 12:02 PM on March 11, 2020 [5 favorites]

Sounds like the perfect material for Titanic's Revenge.
posted by oneswellfoop at 12:10 PM on March 11, 2020

Geoffrey sounds pretty interesting, but I think we really need an FPP on Magnus.
posted by TedW at 12:29 PM on March 11, 2020 [1 favorite]

The durability of pykrete is still debated. Perutz has estimated a crushing strength value of around 1,100 psi (7.6 MPa).

My first surprise: A couple of weeks ago I was testing a lightweight sample of balsa which had a crush strength of 9.6 MPa.

My second surprise: They list concrete as having a crush strength of 17 MPa, with other sources giving 15-30 MPa. Oak gets up to 60 MPa (PDF).

Maybe they should've built their giant floating boat from wood?

(Steel is anywhere from 100 MPa to 2,000 MPa, which I guess is why they usually build aircraft carriers from steel.)
posted by clawsoon at 12:35 PM on March 11, 2020 [1 favorite]

The failure mode you can see in the Hydraulic Press Channel video is really fascinating. Before the material gives way, it melts due to compression heating.
posted by tobascodagama at 12:39 PM on March 11, 2020 [4 favorites]

This was one of the few eps of Mythbusters that I was disappointed with. I thought they were not rigorous enough and they took too many handwavy shortcuts with the newspaper.

MB only lets me down when they aren't as extra as I want them to be.
posted by Horkus at 12:45 PM on March 11, 2020 [3 favorites]

Many years ago, shortly after reading Geoffrey Pyke's TO RUHLEBEN — AND BACK , I was introduced via a friend to Peter Lynch of Project Grizzly fame. After talking a bit about Northern Ontario (where Project Grizzly was shot) he mentioned he was working on a documentary on Project Habbakuk. He was taken aback by my enthusiasm for this odd bit of Canadian history but was happy I was familiar with it. Sadly I don't think his project ever saw the light of day (I could be wrong though?). I always hoped we at least would get a Heritage Minute out of his work on the subject.
posted by Ashwagandha at 12:46 PM on March 11, 2020 [2 favorites]

99PI also has an episode about this!
posted by furnace.heart at 1:05 PM on March 11, 2020 [3 favorites]

Wow — and I thought Nazi leadership was gullible.
posted by jamjam at 5:07 PM on March 11, 2020

Ice-9, for when you want nothing to ever melt again.

Or you like to mix your Vonnegut with your Satriani.
posted by mandolin conspiracy at 5:42 PM on March 11, 2020 [1 favorite]

Pyke was a fascinating and ultimately sad guy.
posted by doctornemo at 2:03 PM on March 12, 2020 [1 favorite]