Britain's bergship: A 1/350 scale HMS Habakkuk "ice" aircraft carrier.

[NARSES2]

Fascinating to see it all laid out like that 

[seadude]

And throughout this thread, I probably should have added more information concerning the material known as Pykrete.
Fear not, here are some of my opinions laid out below on the subject. If any of the links don't work, please let me know and I'll try to correct them.

WHAT IS PYKRETE?

Anybody who has ever researched Project Habakkuk will undoubtably come across a word known as "pykrete". But what is pykrete?
http://en.wikipedia.org/wiki/Pykrete

In short, pykrete can almost be thought of as a "super ice" so to speak. It is a composite material made up of approximately 86% water and 14% wood pulp, by weight.
Due to its low thermal conductivity, it has some amazing properties:
1. Can be molded, shaped, and cut into any form.
2. Extremely slow melting rate due to low thermal conductivity.
3. Can float and is unsinkable.
4. Almost (but not quite) immune to various forms of ordinance, specifically bullets, bombs, torpedoes, etc.
5. Stronger and tougher than regular ice.
6. Almost as strong and tough as concrete.
7. Pykrete can be made with the Earth's most abundant material: Water. Any water should be able to work such as tap water, salt water, fresh water, distilled water, etc.

But for all its advantages, pykrete has disadvantages as well:
1. Must be kept at, or below freezing temperatures.
2. Not immune to "heat" type weapons such as napalm, thermite, etc.
3. Will still crack/shatter if enough force is impacted onto it depending on the type of force used.
4. While the ratio of 86% water and 14% wood pulp are common amounts given in various sources, the type of wood pulp can be a factor as well. Wood pulp such as, but not limited to: Sawdust, Shavings, Newspaper, Cotton, Spruce, Fir, Pine, Cedar, Oak, etc. can either enhance or detract the properties of pykrete.
5. Depending on the size of the form/shape/mold of the pykrete object being made, the object may take hours, days, or even weeks to freeze solid.
6. Pykrete needs proper cooling and refrigeration systems in order to keep it frozen.

The wood pulp mixed with the water would most likely be in the form of shavings. Not necessarily sawdust. And when mixed properly, the mixture would take on the consistency of probably oatmeal, but much, much thicker, kinda like a really thick sludge almost. And will generally have a tan or brownish type color.

THE SECRET OF PYKRETE.

What exactly makes pykrete so special? What really gives it it's strength? I'm not an engineer or a scientist, so I can't really say. But after much research, the type of wood pulp used and mixed with water is a strong factor. But if you do more research and read about wood and wood pulp, you'll learn that it is composed of cellulose fibres.

https://en.wikipedia.org/wiki/Wood
https://en.wikipedia.org/wiki/Pulp_(paper)
https://en.wikipedia.org/wiki/Wood_fibre

If the Pulp link above doesn't work for any reason, don't blame me. It's Wikipedia putting stupid parenthesis around a word which is screwing up the link. 
Anyway.........what scientists like Max Perutz, as well as others from Canada's National Research Council found out was that longer cellulose fibres in various woods create better tensile strength in the pykrete. Searching on Google for the following document will explain more.

Perutz, M. F. (1948). "A Description of the Iceberg Aircraft Carrier and the Bearing of the Mechanical Properties of Frozen Wood Pulp upon Some Problems of Glacier Flow".
The Journal of Glaciology. Vol.1, Issue 3, 1948, Pgs. 95-104

https://www.cambridge.org/core/journals/journal-of-glaciology/article/description-of-the-iceberg-aircraft-carrier-and-the-bearing-of-the-mechanical-properties-of-frozen-wood-pulp-upon-some-problems-of-glacier-flow/BE12BCCE68FE5D9C307299A2F1F2DFC6

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/BE12BCCE68FE5D9C307299A2F1F2DFC6/S0022143000007796a.pdf/a-description-of-the-iceberg-aircraft-carrier-and-the-bearing-of-the-mechanical-properties-of-frozen-wood-pulp-upon-some-problems-of-glacier-flow.pdf

As for which woods and wood pulp would ultimately be good for making pykrete, I have no idea. Anybody who makes pykrete is just going to have to do their own "scientific" research and experiments to find out what works best and what doesn't.
If I had to take a guess and say what would be good for making pykrete, my first two answers might be shredded newspaper, and also wood shavings.....the kind used as bedding in horse stalls.
A lot of pics and stories I've seen by other people tend to show sawdust as being used to make pykrete. IMO, I tend to feel this is ill suited and will not work very well. Simply because the sawdust particles are too small. If pykrete is to be made, then you need wood pulp that has a bigger surface area, denser, and where the cellulose fibres are much longer. Hence why I think samples of shredded newspaper and wood shavings might be preferable options.

[seadude]

Just a few other bits of information to add here.   But I should have another model progress picture available either Tues. or Weds.

I found the below picture on the Net. Unfortunately, it's in French, so I can't translate it. But anyway, its an artist interpretation of a Habakkuk type vessel compared to the sizes of a B-52 bomber aircraft (Far right center of pic), a U.S. Navy Gerald Ford class aircraft carrier (Lower left of pic), and a World War 1 dirigible airship (Lower right of pic). It gives you a good impression of just how big the Habakkuk would have been compared to other items.
Contrary to what some people may see and think when viewing the picture, a B-52 bomber aircraft and/or any other large similar sized aircraft (B-36, Lancaster bomber, etc.) would not be able to take off or land from the Habakkuk. A large aircraft such as the B-52 requires takeoff distances of 7,000 to 8,000+ ft and landing distances of 5,000+/- ft. This is far in excess of the Habakkuk's 2,000 ft long flight deck.
To find out if a small, medium, or large sized aircraft can take off or land on the Habakkuk, it may be necessary to find out that aircraft's takeoff and landing distance requirements. Other factors that may determine how much takeoff or landing distance an aircraft needs can include, but is not limited to the following: Winds (and other environmental factors), Runway conditions, Weight of the aircraft (Loaded or unloaded), Engine performance/thrust, etc.
Below the picture is a Youtube video I came across while browsing the Net. Now I'm not very fond of YT videos about Project Habakkuk since a lot of them seem to get things wrong and just plain sensationalise the crap out of the Habakkuk. But this video is one I like because it is narrated by Prof. Susan Langley who is an underwater archaeologist who has dived in Patricia Lake to view and record the remnants of the Habakkuk prototype. So I trust her analysis and documentation of the history of Project Habakkuk. .

[NARSES2]

Thank you for that, very informative 

[PR19_Kit]

Interesting that the 'Ford' is getting on for the same beam as the Habbakuk, or the deck is anyway.

[seadude]

Interesting that the 'Ford' is getting on for the same beam as the Habbakuk, or the deck is anyway.

Doesn't look like both have the same beam (width) to me? Maybe the picture is a little off as far as scale. I don't know.
The Habakkuk hull has a width of 300 ft (91 meters) without motor nacelles attached, and a total width of approx. 340 ft (103 meters) with motor nacelles attached.
The Gerald Ford class carrier has a total width of 256 ft (78 meters).
So anyway...........close, but not close enough.

[PR19_Kit]

That's 85% of the Habakkuk's width, close counts! 

I did say '.........getting on for...........', maybe it lost something in translation.............

[Old Wombat]

That's 85% of the Habakkuk's width, close counts! 

I did say '.........getting on for...........', maybe it lost something in translation.............

Yes, English-to-English can be a bit tricky at times.

[seadude]

The left side of the Habakkuk interior cross section is all done with my cut "ice blocks" used to fill in that side. The right side won't be completely filled with ice blocks. Near the bottom is where I placed an example of a maintenance access shaft that would run from the central habitation & engineering area to the motor nacelle which would be located on the exterior of the hull.
Now that access shaft is for the lower row where a motor nacelle would go. I can't make an upper access shaft for a motor nacelle in the upper row nor can I add a motor nacelle itself to the cross section as the distances between the motor nacelles (See chart further below.) are too great. All I really need to do for the cross section is show "examples" of where motor nacelles would be, location of an access shaft, and any other details.
If I really wanted to show a cross section with the full distances between the nacelles as well as all access shafts for both the top and bottom rows of nacelles, then the length of my interior cross section would have to be far longer than the 3" inches I made for it. So..........there will eventually be a lower motor nacelle on the right side of the cross section "connected" to the access shaft. But there won't be a motor nacelle in the upper row on the right side of the cross section. As for the left side of the cross section, again, there will be a lower motor nacelle attached to the left side to match up the one on the right side. The left side won't have an access shaft as I want one side to be completely filled with
ice blocks, while the right side is to show an example of where an access shaft would go.
Did I make everything clear or are people confused yet?
Well, trust me. Everything will work out as I long as I plan things accordingly and do some proper and careful thinking.
And when this interior cross section is eventually finished, hopefully, you'll get a better understanding of everything.

So why are the left and right areas on either side of the central crew habitation section to be filled with ice? Let me rehash this again for people. Also take a look at the fifth and sixth pictures below.

Contrary to popular belief, the interior design of the Habakkuk vessel was not the following as shown in the fifth picture below as well as in other media sources. 
The illustration (Fifth picture below) is from an article in the Illustrated London News, Pgs. 14 and 15, Saturday, March 2, 1946, No.3071, Vol. 115 or 118?
This interior illustration of a Habakkuk vessel design was most likely based on a press release that was given to the public and media in 1946 by Canadian and/or British government and military figures. The interior illustration is wrong in that it shows upper and lower port & starboard aircraft hangars on either side of the central crew and engineering levels.
As has been shown in other schematics in this thread, the left & right areas on either side of the center crew and engineering areas were to be filled with a "resin block construction" mainly consisting of regular ice with possible addition of other non-pykrete materials. According to The Canadian Habbakuk Project book by Lorne W. Gold, the ice block construction used in the areas on either side of the central crew area was to be for mainly buoyancy (and/or structural integrity) issues. The following describes more about the use of ice from the book:

"Initial studies were based on the use of a pykrete shell (hull) with inner supporting columns and bulkheads made of either concrete or pykrete. However, the resulting designs did not comply with condition B (The vessel to be unsinkable with all compartments flooded.). When all compartments were flooded, a vessel with the inner structure of concrete would definately sink. Under similar conditions, the all-pykrete vessel would lie so low in the water as to render it useless. To overcome this difficulty, it was decided to use a lightweight non-absorbent filling material in the interior of the vessel so that the necessary buoyant effect could be obtained and the craft still remain unsinkable. The general outline of the proposed design is shown in Figure 1 (See the sixth picture below.). It consists essentially of an outer pykrete shell supported internally by hollow reinforced concrete columns and with spaces between columns filled with a suitable material weighing not more than 25 lbs per cubic foot. Ice containing at least 60% air bubbles or voids has been proposed for this material."

NOTE:  Bubble or void ice refers to blocks of regular ice (Not pykrete) that have air bubbles inside of them or where the blocks of ice are more like a hollow brick of sorts.

In short, any media source that shows the interior of the Habakkuk to look like the fifth picture below with port and starboard aircraft hangars is wrong. I suspect the media misinterpreted the press release (Either accidentally or intentionally), but decided to just go ahead with what they wrote and drew to sell their paper, make a few bucks, and just give the public what they wanted: A wild and incredibly fantastic news story.

[seadude]

And now for something different. 

If anybody is looking for any fictional books "slightly" related to Project Habakkuk, Here's two I found.
FAST ICE novel by Clive Cussler. Though you really won't find anything related to Habakkuk till you get to Chapter 50 and afterward.
https://www.amazon.com/Fast-NUMA-Files-Clive-Cussler/dp/0593327861

This next book I have, but haven't read it yet. It's based very loosely on Project Habakkuk, but with a bunch of places and people's names that have been changed.
AT THE WOLF'S DOOR novel by Chaz Ozburn.
https://www.amazon.com/At-Wolfs-Door-Novel-WWII/dp/1555719414

[seadude]

The pictures below are diagrams (Shown on previous posts in this model thread.) that I colored to show a more simplistic representation of the interior spaces of a proposed Habakkuk vessel. Original diagrams (before coloring) are from an article titled "HABAKKUK" by William J. Wallace, WARSHIP magazine, Vol.5, No.18, 1981, Pages 80-85.

[seadude]

Not much new to report. Still working on building the interior cross section.
Though in the next few days, I may shift toward trying to build one of the main hull sections for my model.
Since trying to get a plastics company to make the hull sections for me fell through, I'll try to see what I can do myself.
In other news, whatever I've got done for this entire model project, I'm going to take with me to a model ships & boats contest for display only in 3 weeks to show others what I am working on.
Boy, won't they be surprised and shocked when I tell them this will be a nearly 6 ft long model.      They'll probably think I'm nuts.

[jcf]

Have you considered making the majority of the hull
out of wood? You could then plate it with plastic, if
so desired.

[seadude]

Have you considered making the majority of the hull
out of wood? You could then plate it with plastic, if
so desired.

That's what I did for my 1/700 scale Habakkuk model almost 15 years ago. Pics are below. I had a friend (who did carpentry in his spare time) make the hull out of wood for me since I couldn't think of what else to use at the time. But to the best of my knowledge, the last time we talked which was 2 years ago, he got rid of all his saws and other carpentry tools in his garage for various health and other reasons. And I don't know of anybody else near me that does wood/carpentry work. So getting a 1/350 scale Habakkuk hull made out of wood is out of the question.

[seadude]

You know that old addage of "measure twice, cut once"? I never learned it very well in shop class in high school and I still haven't learned it very well when building models. 
Anyway.............
To start with, what you see below in the first few pics is a wood box I asked someone to make for me long ago when I started to think about building a 1/350 scale Habakkuk maybe 5-7 years ago. Think of the box as sort of like a mold or drydock for helping to build the center hull section portion of the Habakkuk model.
But, the box has wrong interior measurements. I never got the box updated or even considered getting a new box made. Whoops. 
The measurements aren't that far off. But for what I've built so far for one of the center hull sections, this hull piece will just be a prototype or for display only or something?
I'm not going to use it as an "actual" hull section for the actual 1/350 scale model. I don't want to go into a long story, but I've made too many mistakes building it.
As I said, I didn't "measure twice, cut once" when building it. It's just not up to spec.
I guess the only reason I used the wood box and tried to build a center hull section was because I had trouble with not getting a plastics company to make the center hull sections for me. So I wanted to see how far I could do things on my own. So I'll finish building this prototype center hull section piece for now. Maybe I'll go back to the plastics company and try talking to them again and get a different quote and see what other materials they have that might be cheaper. I might take the prototype hull section with me to show to the people at the plastics company what I want done. Only time will tell. We'll see what the next few weeks or months have to offer.