Korean Hwacha

Origins

Korea learned gunpowder from China, and in 1377 the Goryeo official Choe Mu-seon established an office for gunpowder weapons, primarily to fight the Japanese pirates who ravaged the coast. His son, Choe Hae-san, built the first hwacha in 1409, early in the Joseon dynasty, and under the scientifically minded King Sejong and his son Munjong the weapon was refined. The 1451 Munjong hwacha, recorded in detail in the court's military manuals, became the standard design, and the Gukjo Oryeui Seorye of 1474 gave precise drawings and measurements of its rockets and launch frames. Korean fortresses kept stocks of hwacha for the defense of walls and passes.

Design & Construction

A hwacha is a light two-wheeled wooden cart, carrying an inclinable rack that could be aimed by raising or lowering the frame. The best-known rack held a hundred singijeon, arrows about a meter or more long with a paper tube of gunpowder fixed near the head as a rocket motor, and some carried a small charge in the head. The fuses were linked together, so all the rockets could be fired in rapid succession by a crew of two or three; the whole cart could be pushed by one or two men. An alternative rack mounted about fifty sajeonchongtong, small gun barrels each firing several arrows. A salvo covered an area rather than a single target, and the noise, smoke and trails of fire made it as frightening as it was destructive; rocket range was several hundred meters, but accuracy was modest. Hwacha were cheap to build and could be massed along a wall.

Combat Use

The hwacha's reputation rests on the Imjin War, when Toyotomi Hideyoshi's armies invaded Korea in 1592 with Samurai armed with the Matchlock Musket and the Katana. At the Battle of Haengju in February 1593, General Gwon Yul held a hilltop fortress with some 2,300 men — soldiers, warrior monks and civilians — against a Japanese army many times larger; his defenders used hwacha, bigyeokjincheonroe explosive shells, arrows and stones to repel repeated assaults, and the Japanese withdrew with heavy casualties. Haengju is remembered as one of Korea's three great victories of the war, alongside Admiral Yi Sun-sin's naval campaigns and the defense of Jinju. The hwacha was essentially a defensive weapon, dependent on the enemy coming within range of prepared positions, and it did not transform open-field battle.

Legacy

Joseon armies continued to use rockets and hwacha into the seventeenth century, but the weapon faded as artillery and firearms improved. Today it is a symbol of Korean ingenuity, displayed in museums such as the War Memorial of Korea in Seoul, depicted in Korean historical dramas about the Imjin War, and tested in modern reconstructions that fire successfully. It is among the earliest multiple-rocket launchers in history, a line of descent to modern rocket artillery that also includes the Chinese rocket arrows from which it grew. See Korean Arms & Weapons and, for the earlier mechanical artillery it replaced, the Trebuchet.