[2][3][4] The panokseon served as the base for the Korean warship type called the geobukseon, which was used to great effect during the 1592-1598 Japanese invasions of Korea.

[5] A flat keel enables a ship to sit comfortably on the tideland when the tide is out, after coming ashore or inside a wharf at high water.

[citation needed] It also ensures greater mobility, a shallow draft, and in particular allows a ship to make sharp changes of direction at short notice.

[6] The panokseon's features were among the main reasons why Admiral Yi was able to employ the Crane Wing formation at the Battle of Hansan Island with great success.

[citation needed] When the Age of Discovery began in the fifteenth century, multiple-masted ships equipped with both types of sails eventually appeared.

[citation needed] The panokseon therefore had two masts by default, and possessed sufficient crew such that their position and angle could easily be managed so that the sails could be used in all winds, whether adverse or favorable.

By having multiple levels the rowers at the bottom were relatively safe, and marines at the top would have a height advantage over the enemy, firing down upon them and avoiding boarding of the ship.

[3] The development of artillery steadily continued after King Sejong, and saw the invention of the bigyeokjincholloe, a timed grenade that flung out hundreds of metal shards upon explosion, and the dapoki, a machine capable of firing many arrows at once.

[citation needed] By the time of the Japanese invasions of Korea, the cannons used by the Korean naval forces were capable of firing a variety of projectiles, including fragmenting iron shot, stones, and buckshot, several hundred yards.

[10] Among the most feared projectiles fired by the Earth cannons was a ballista-like large iron arrow covered in incendiary material, which was used to great effect against Japanese ships.

[2] A sharp underside was favorable for swift or long-distance travel in the open seas because of lower water resistance (thus these ships had faster cruising speeds).

Since this variety of hull had a deep draft (penetrates deeper into the water), however, the turning radius of such ships was considerably large and changing direction was therefore a lengthy process.

[citation needed] The atakebune ship type was an exception in that it had two masts, but the main parts of its vessels were square-rigged and their sails were again limited to use in favorable winds.

The sekibune in particular, being the standard warship of the Japanese fleet, was built primarily as a transport ship and to be as light as possible, increasing its speed at the expense of structural integrity.

[2][4] This is consistent with traditional Japanese naval tactics of the time, which emphasized boarding enemy ships and engaging their crews in hand-to-hand combat.

[2][4] The Japanese warships, on the other hand, relied on iron nails which, as time passed and corrosion and rust set in, eventually weakened the hull.

[3] During Hideyoshi's invasions of Korea, a vast number of Japan's transports and warships were destroyed by Admiral Yi Sun-shin's leadership, initiative, superior firepower, tactics, and knowledge of strategy.