Imagine an aircraft carrier made of ice that’s bullet‑proof and self‑repairing - built for only 1 % of the steel cost. That was Project Habakkuk. But trials showed pykrete sagged unless constantly ...

Project Habakkuk was a wartime proposal to build an enormous aircraft carrier from “pykrete,” an ice-and-wood-pulp composite pitched as strong, slow to melt, and difficult to sink. The transcript ...