— The Patricia Lake Project —

— testing the Habakkuk concept —

The finished "Boathouse" Habakkuk model afloat on Lake Patricia

As an initial investigation into the viability of 'Habakkuk', a 1/10th scale model (in width and height, though not length) was constructed in early 1943 on Lake Patricia in the Canadian Rockies. It was built from blocks of ice cut from the lake [not Pykrete!] with embedded air ducts for refrigeration.

Begun in February, it was completed by April. The plug was pulled in June... literally — the refrigeration was turned off. The packed ice blocks lasted well through the summer, until it finally sank.

Construction in progress:

Building the framework
Insulation and refrigeration duct
Final ice block floor layer
Cut loose from the ice

In 1985 Dr. Susan Langley, then at the University of Calgary, did an underwater survey of the lake site, and she has an extensive discussion of the project and her findings (in PDF form, 800kB) at http://id.erudit.org/iderudit/800233ar. This is a very well researched report, though I'd quibble with the attribution of 'Pykrete's naming to Hermann Mark; Perutz claims he coined the name, and I'm not sure that Mark's research was associated directly with Habakkuk at all. [And note that the two other lakes she mentions were not associated with the Habakkuk project. They are other historical sites she investigated at the same time.] Langley is said to be currently writing a book on the Lake Patricia project.

[I believe these photos are Crown Copyright (National Archives), and thus permissible to use on this site.]