World War II was filled with a lot of interesting inventions and military hardware used by a lot of countries. Some of which were used, and some of which were oddball and crazy, and never made it beyond the prototype stage. Take for example: Project Habakkuk.
Conceived and proposed in 1941 by eccentric British inventor Geoffrey Pyke, Project Habakkuk was a “monumental” plan (LOL!) to make an aircraft carrier out of ice, or rather a “super ice” known as Pykrete (Named after Geoffrey Pyke.), for use against German U-boats in the mid-Atlantic ocean which were out of range of land based Allied aircraft. This super ice was made with nothing more than water and wood pulp (86% water, and 14% pulp, by weight.), and then frozen. The consistency of the mixture before freezing would be comparable to oatmeal, but much thicker.
Pykrete has some rather interesting properties:
1. Relatively slow melting rate (due to low thermal conductivity).
2. Vastly improved strength and toughness over unmodified (crystalline) ice, actually closer to concrete.
3. Could float and was unsinkable.
4. Nearly impervious to various types of ordinance.
Pykrete is slightly more difficult to form than concrete, as it expands during the freezing process, but can be repaired and maintained from the sea’s most abundant raw material: Water. The mixture can be molded into any shape and frozen, and it will be extremely tough and durable, as long as it is kept at or below freezing temperatures.
Pyke then proposed the idea to Lord Mountbatten, who was Chief of Combined Operations, who then pitched the idea to Britain’s Winston Churchill. As an initial investigation into the viability of “Habakkuk”, a 1/10th scale model (In Width and Height, but not in Length.) was constructed in early 1943 on Patricia Lake near Jasper, Canada to test building materials and construction techniques. It was built from blocks of regular ice (Not pykrete.) cut from the lake with embedded air ducts for refrigeration.
Begun in February 1943, It was completed in April the same year. Although the prototype was a success in proving the validity of such a concept and the construction techniques used, the plug was pulled in June…….literally, and the refrigeration equipment was turned off. The structure lasted well through the summer until it finally sank to the bottom of Patricia Lake.
Specifications for the prototype were the following:
Height: 18-20 feet
Width: 30 feet
Length: 60 feet
Weight: 1000 tons
Construction Crew: 15-20 men.
Although the Habakkuk prototype was successful, Full scale construction of a massive Habakkuk carrier never took place due to financial costs, limited resources, plus the fact that Allied aircraft were flying longer ranges to scout for U-boats as the war progressed. Research was halted in early 1944 for a number of reasons: the growing numbers and effectiveness of conventional carriers, the huge cost ($100 million) involved, and the technical difficulties of building and refrigerating such a massive structure.