Let's Build Ships Out of Ice!: "Project Habakkuk"

Like many things, it probably sounded good at the time.

From 99% Invisible:

Project Habakkuk

At the bottom of Lake Patricia, in Alberta Canada, you’ll find a shipwreck. Denise Boniface of Aquanuts Diving  has seen it.

“It doesn’t really look like a ship,” says Boniface, it’s more like “a pile of lumber that’s all broken up and laying there” — also: “a lot of refrigeration coils.” And if you go down far enough, you can shine your light on a plaque:

“Operation Habbakuk – A secret WWII project involving the use of ice in ship construction. This vessel, built January to April 1943, was a prototype. For more information contact the Canadian Park Service in Jasper.”

In the early 1940s, German submarines (U-Boats) were wreaking havoc on Allied ships in the Atlantic ocean. Eventually, Lord Mountbatten, Chief of Combined Operations, went to Winston Churchill to suggest an extreme solution: a massive, unsinkable aircraft carrier made of ice....

....MUCH MORE
 
Maybe you had to be there.