Camouflage is usually about blending in, but some of the most unusual camouflage during World War I wasn’t designed to do that.

Dazzle camouflage was a popular camouflage method, as the above video shows. Instead of attempting to hide a ship, the goal was to conceal the ship’s course through flashy misdirection. These colorful ships had artistically adventurous patterns that, due to the limitations of U-boat periscopes and torpedoes, were surprisingly effective at keeping ships safe.

Submarines and torpedoes were a big, new threat in WWI. Despite this, the U-boat had limitations: torpedoes required calculating the target’s trajectory. Factors like the angle a ship was traveling, its speed, and its distance from the U-boat itself all came into play. These things were usually determined by eye, through a periscope, or using a rangefinder.

Dazzle patterns made it a lot harder to determine a ship’s trajectory, because they helped hide key points of reference for torpedoes, like the ship’s overall orientation. Today, dazzle patterns are still used in types of face camouflage, and by car manufacturers when prototyping new models.

This video shows the basics of this unusual camouflage. If you want to learn more, you can explore the Navy’s archive of dazzle camouflage history, read this 1919 Popular Science article about the technique, or explore the life of Norman Wilkinson, the artist credited with inventing dazzle camouflage.

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