In a riveted ship, a crack usually stops when it hits the edge of a plate. In a welded ship, the entire hull is one continuous piece of metal. Once a crack started at a square corner in cold water, it could zip around the entire hull at the speed of sound.
During the 1940s, the U.S. needed to build cargo ships faster than ever before. To save time, engineers switched from traditional to welding . On paper, the steel (Grade A) had sufficient tensile strength to handle the heavy cargo and rough seas. Applied Strength of Materials
This shift transformed naval architecture and remains a foundational lesson in why calculating isn't enough; you have to understand how geometry and environment change how a material behaves. In a riveted ship, a crack usually stops
However, the ships began to fail catastrophically. In some cases, a ship would literally snap in half while sitting at the dock or sailing through the freezing North Atlantic. The "Applied" Engineering Reality During the 1940s, the U