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Can A Hailstorm Sink A Boat? | MythBusters

The MythBusters tackle a classic fisherman's tale: can a hailstorm really sink a boat? They investigate whether hail can penetrate a boat's hull or if the sheer volume of ice can cause it to lose buoyancy.

MythBusters · August 26, 2026 · 23-min episode · 4-min read

Can A Hailstorm Sink A Boat? | MythBusters

Key takeaways

⚾The myth suggests hailstones the size of baseballs can sink a boat, raising questions about whether it's due to penetration or the sheer volume of ice.00:15
👨‍🏫Professor John Monteverdi confirms that hailstones can indeed grow to baseball size and travel at speeds capable of causing significant damage, potentially punching holes in boats.01:40
🧊Kari crafts perfect baseball-sized ice spheres from clear ice blocks, ensuring they are as hard as possible to simulate real hailstones.02:47
🔫Grant builds a 40-foot long cannon designed to fire the ice balls at speeds up to 300 miles per hour, simulating extreme wind conditions.03:49
🛡️Initial penetration tests on boats on land at 80 mph and 150 mph show no holes, only dents, even at hurricane-force speeds.05:43
🛶The buoyancy test reveals that even with two tons of ice, the boat doesn't fully sink because air pockets between the ice pieces maintain buoyancy, and once water enters, the ice floats.16:19

Chapters

0:00🌊 Introduction to the Hailstorm Myth
0:14🔬 Expert Insight on Hail Formation and Impact
0:43🛠️ Preparing for the Hailstorm: Ice Production and Cannon Construction
5:04💥 Penetration Test: Hail vs. Boat Hulls (On Land)
16:48🧊 Buoyancy Test: Sinking a Boat with Sheer Volume of Ice
28:12💧 The Twist: Penetration Test on Water

The digest

The MythBusters team dives into a chilling maritime myth: the idea that a hailstorm can be so severe it could actually sink a boat. This isn't just about a few ice pellets; the myth speaks of hailstones the size of baseballs. The central question is twofold: does the hail penetrate the boat, causing it to take on water, or does the sheer accumulation of ice in the boat cause it to lose buoyancy and sink? The team sets out to unravel this frosty mystery.

Understanding Hail: Nature's Icy Projectiles

To begin, the MythBusters consult with Professor John Monteverdi, a meteorology expert, to understand the science behind hail. Hail is essentially a glob of ice that grows in the upper parts of a thunderstorm cloud. When it becomes too large, it falls to the ground, often in a large mass. Professor Monteverdi confirms that hailstones can indeed grow to the size of a baseball and can travel at speeds capable of knocking down tree branches. He deems it conceivable that such hail could punch a hole in a ship, depending on the material of the boat and the speed of the hail.