The Berg Ship

In future posts, as well as my home experiments, I will delve further into some of the fantastic personalities and myths behind Project Habbakuk, but here’s a brief introduction.

In 1942, the Allies were under attack by Axis forces in the Atlantic. They needed a way to improve the efficacy of their short-range aircraft, and started to look at ways to provide floating platforms to act as aircraft carriers in the North Atlantic.

Projecy Habbakuk was the brainchild of Geoffrey Pyke, an eccentric who had managed to get the ear of Lord Mountbatten and Winston Churchill. He proposed the construction of vast ships made of ice – its natural buoyancy would protect them from sinking in the event of enemy shelling, and the raw material (water) for their repair was virtually free. However, its brittleness and tendency to creep presented difficulties.

Pyke gained scientist J D Bernal’s support to develop the project. Bernal suggested his former student, Max Perutz, who had worked extensively on the properties of ice. Work was slow to start with, until Pyke sent Perutz a paper referring to the reinforcement of ice with microfibres derived from wood pulp. Tests on this material (given the name “Pykrete”, in honour of Geoffrey Pyke) were encouraging, and Perutz was set up in a lab in the cold stores below Smithfield Market in London.


Pykrete was dramatically stronger than ice and resistant to melting. Military chiefs were so impressed that they instigated a pilot project to build a model ship in Patricia Lake in Canada. The technical issues were extreme, however, and the cost of machinery needed to freeze the wood pulp and of iron for reinforcement of the bergship negated the cheapness of the raw materials. Furthermore, developments in aircraft design and deals made with the Portuguese to use the Azores for refuelling stations had effectively made the project redundant, and the model ship was scuttled in 1943.