Weapons & Warriors: The Hwacha of the Koreans

The first concept of a multi-firing rocket launcher wasn’t invented by the Americans, the Russians, the Japanese, the French, or even the Germans. Believe it or not, the largest pre-firearm multi-rocket propelled grenade launcher was invented by the Koreans. The design was inspired by a smaller and more portable version the Chinese used, but was not as devastating as what the Koreans came up with. Long ago before there was such a thing as North or South Korea, there was just one Korea that was often oppressed by its neighbors. China refused to trade saltpeter to Korea, Japanese invaded, and pirates raided their fishing villages along the coast. So the Koreans learned to make their own gunpowder and in 1409 they created something the world had never seen before.

Art by TL Jeffcoat

The Hwacha was a two wheeled cart that could be tied behind a horse, or other animal and shipped to wherever it was needed. The bulk of the weight was centered between two wooden wheels that were not attached by an axle to give them freedom to turn individually. This allowed the cart more mobility. Once unstrapped, one or two men could tilt and aim it before securing it into position. The thing was completely made from wood, usually pine. The top was a hollow box with around 200 tubes in it. This was where the arrows were placed.

The ammo was a specifically designed arrow over a meter in length with a tube of black powder strapped to the side. These projectiles were basically bottle rockets with huge arrowheads at the tip and feathers on the rear to keep it straight in flight. Once the rockets launched the arrow it could travel around 100 meters (around 300 feet) to its target. Although a canon had more destructive power and range, the Hwacha was more effective against a marching army which would be generally close together as waves of Hwacha arrows slammed into them. The heavy arrows had enough force behind them that they could completely penetrate an armored soldier.

The Hwacha was the answer to the outnumbering forces always attacking them. Each Hwacha was the equivalent of 200 archers firing explosive arrows. Could you imagine 50 of these things lined up? That’s 10,000 arrows fired in less than a minute and all of them with explosive power. If the arrow didn’t hit a vital organ, the explosion would take you out of the battle. This explosive power was very destructive against pirates and Japanese ships as well. Wood always loses to explosives. If the hull isn’t breached and leaking, the fires would take care of the vessel. If the hundreds of arrows taking out clusters of troops weren’t enough to break moral, then the loud popping explosions from those hundreds of arrows might unnerve the bravest warriors.

Many Hwacha were used in defense and placed on the walls of castles and fortresses. They were in a safe location for constant reloading and firing and high enough to increase their range by two or three times the normal distance. The Koreans built hundreds of these things. The only downfall was the enormous amount of time for setting up a round to fire. There was no cartridge full of projectiles, so someone had to insert each arrow individually then place the igniters for each arrow. Once the igniters and ammunition was in place however, it only took one pull of a rope to light the igniters which lit the gunpowder and fired the arrow.

Fortunately the Hwacha was a light weighted machine and could be moved away after firing within minutes so it wasn’t lost to the enemy. Then it could be reloaded from a safer distance and maneuvered back into combat. Most often the Hwacha was aimed at the troops directly in front of it, so there would be time to back away if needed while the line attempted to reform. A common tactic was for Koreans to build trenches and surround the Hwacha with defense troops so that they fire into the attacking troops that were already struggling to get to the Korean soldiers behind the spiked logs.

Here’s a video of a Hwacha built on the set of Mythbusters then tested to show how it worked and how effective it could be.

I hope you enjoyed this edition of Weapons and Warriors, click here to view the entire catalog of weapons and cultures. Thank you, see you next week.