An Amazing Idea – Making An Aircraft Carrier Out of Ice and Sawdust

Geoffrey Nathaniel Joseph Pyke
Geoffrey Nathaniel Joseph Pyke

Pyke preferred to be more proactive, so he proposed an aircraft carrier 2,000-feet long and 300-feet wide – made entirely out of ice. It would weigh about two million tons, and if bullets and missiles destroyed some of it, then it could be easily and cheaply repaired. Better yet, it needed no fuel to stay afloat.

The ship was to have an airstrip capable of holding 150 fighter planes and twin-engined bombers. For weapons, it would have 40-dual-barreled gun turrets, as well as anything they needed against German ships, planes, and submarines. Simply find an iceberg and carve it out!

There were, however, two problems. Ice tips over in water and is fragile. The idea was abandoned, but the Americans were now intrigued. Herman Francis Mark (a chemist and early contributor to polymer science) solved the problem. Ice becomes more durable and flexible if sawdust, paper shreds, and wood chips are added.

Done properly, it could be as strong as concrete, more buoyant, and slower to melt than pure ice. Better yet, it could be cut and shaped just like wood. Theoretically, an aircraft carrier could indeed be built out of it.

Screw-propelled prototype of the Weasel Photo Credit
Screw-propelled prototype of the Weasel Photo Credit

Models were constructed beneath London’s Smithfield Meat Market to make use of their frozen meat lockers. It was promising, so they made bigger models in Canada’s Jasper National Park. Later, they made a 1,000-ton, 60’X30’ model at Patricia Lake in Alberta and fired salvos at it to see how it stood up to bullets and explosives.

After more tweaking, Canadian engineers felt they could make a 1,000-ton model and have something workable by 1944. Churchill was ecstatic and ordered one ASAP, promising the Canadians even more business if they could pull it off.

There was one problem they could not get around – “cold flow,” also called “creep.” This is when solid objects deform because of mechanical stresses, especially when heated. Arctic temperatures change, and as people, equipment, planes, and weapons were to be loaded onto the carrier, it would buckle and warp.

As such, Pyke concluded it could not be achieved, but Mountbatten refused to give up. Attending the First Quebec Conference in mid-August 1943, he presented Pykrete to the attending Allied generals. To prove it was bullet-proof, he shot it with his gun… the bullet ricocheted against Admiral Ernest King’s leg!

Mackenzie King (left), Franklin D. Roosevelt (center), and Winston Churchill at the Quebec Conference
Mackenzie King (left), Franklin D. Roosevelt (center), and Winston Churchill at the Quebec Conference

Despite that, the Americans were impressed. Such a ship would allow them to attack Japan from the Aleutian Islands. They could save lives and avoid brutal jungle warfare! Given that Pyke had already clashed with the Americans over Project Plough, he was removed from the project.

Another $3,128,750 was put into Habakkuk before the Canadians started having doubts. The military wanted a pykrete ship with a range of 7,000 miles and be able to stand up to the biggest waves. They also wanted it torpedo-proof and able to support heavy bombers.

That meant a rudder over 100 feet high, a hull at least 40 feet thick, and a deck at least 2,000 feet long. To do that, they needed metal beams. They also needed to figure out how to mount a rudder that big.

They still had not solved the issue of creep. Not without expensive refrigeration and insulation.

By then, the war was turning in the Allies’ favor. Without America’s vast resources and massive industrial might, building an experimental pykrete aircraft carrier was no longer practical.