We have learnt about different types of ships including ice breakers but have you heard about ice boats. This article not only explains this seemingly strange concept but also tells how to build an ice boat? The story goes something like this - A British inventor Geoffrey Pyke came up with an idea of making a huge floating platforms made from ice. These floating platforms were proposed to be used as torpedo proof aircraft carriers that would protect north Atlantic shipping lanes. The idea received the “green signal” from the British War office in 1942. Few months later, Pyke’s former professor and his assistance discovered that sawdust or wood pulp makes the ice platform stronger if added before freezing the water. They named this material pykrete, in honour of Pyke. But before any prototypes were built, long range aircrafts took over the task of protecting the north Atlantic shipping lanes. The ice ship concept was largely forgotten.
Revisiting the Idea
Even after all these years, the concept still seems to be floating around. Adam Savage and Jamie Hyneman, from the famous Discovery channel series Mythbusters, decided to revisit the idea. They decided to build a small boat on the same concept but the materializing of the idea seemed quite dicey. This was because the boat being comparatively small in dimension, would carry a thin pykrete hull which would not hold for a long time.
Thus the same method of using plywood which was discovered earlier, was used in order to bolster the ice plant. Wood pulp, a substitute for plywood was used for this purpose. It was a known fact that the most widely and easily available source of wood pulp is news prints. The experimenters decided to use laminated newspapers in order to increase the structural strength.
Making of an Ice Boat
The first thing that bothered the makers was to make that the newspaper version of pykrete was stronger than the conventional wood pulp one. The test unveiled that the newspaper version, though tough was brittle. The problem was compensated by using 2 inch thick newsprint plank instead of a thinner one, which when tested exhibited properties equivalent to a 2 inch thick plywood.The design of the boat was kept similar to that of a flat-bottomed boat. This would ensure the boat to sail with less horsepower and would also make it easier to construct.
The whole project was made in Alaska in order to find the necessary cold but non freezing water for the project.Also,to make sure the newsprint planks remained intact, a freezing van was hired.Wood pulp was made by putting thousands of newsprint and publications in tubs of water.
The design of the mold consisted of an enclosed wooden box made out of plywood of width 8 feet , length 20 feet and thickness 3/4 inch . The sides were held together with galvanized brackets and were also nailed and glued.The outer side of the mold was lined with a flexible polythene film, which would act as a water seal. The newsprint were laid on the mold in a pattern similar to that shingles of a house, i.e. to put one newsprint at a time in such a way that each joint of two newsprint is covered by the mid section of another newsprint. This would facilitate the water to flow over the layers and not under them.
Also, when water freezes it expands. Thus if proper weight was not kept on the newsprint, they would deleminate. To ensure that this doesn’t happen, an inner mold was made. A 150 horse power four stroke Yamaha engine was mounted on the boat when it was in the cold storage.
In order to make the boat absolutely sea worthy, it was also installed with steering, gas tank, battery and running lights. A proper testing of the machine was done by the makers themselves, wearing mustang survival suits. The boat was started with a speed of 25 mph and was then gradually increased. The leaks that erupted on the way, were sealed with carbon dioxide fire extinguishers.
The only drawback of the boat is that it doesn’t last long due to the heat generated as a result of stresses and friction. But yet it is a novel concept that needs more research and attention.
Can you build ship out of ice? The mythbuster investigates by Jamie Hyneman
- ICE BOATING: A Complete Guide to Ice Boat Development, Design, Construction, and Sailing from D. Van Nostrand Company, Inc.
- Popular Mechanics