Hulls and Sails!

Now I wanted to look into the designs of Chinese Junks, below is my first look into the thought behind the Hulls and Sails:

The design of the hull was Unique, they were made from softwoods with multiple compartments accessed by separate hatches and ladders. The interior structure was made from Bamboo. Traditionally, the hull was horseshoe- shaped stern supporting a high poop deck (poop deck is technically called a stern deck, which in sailing ships was usually elevated as the roof of the stern or "after" cabin). The bottom of the ship is flat with no keel, the boat relies on a very large rudder to steer the ship.

Now the Sails:

The design of the sails was key to the movement of the Junk to sail and to be fast. They weren't the traditional square rigged ship sails but the sails on the junk can be moved inward, tilted the the long axis of the ship allowing the junk to sail into the wind. (picture above shows the mast and sails being aimed into the wind by lowering and angling them)

Also the sails included horizontal members called "battens". These provided shape and strength. Unlike typical sailing boats the Junks had lines attaching each batten to its trailing edge where on a normal sailing boat it would be attached only at the boom. The sails can also be easily steered and adjusted for fullness, to moved to catch various wind strengths. Having these battens would make the sails more resistant that traditional sails to large tears. If there was a tear it would be normally only with in that single panel of battens. Junk sails have much in common with the most aerodynamically efficient sails used today in windsurfers or catamarans. (top image of the 3 would best explain the layout of the sails)

The sail-plan is also spread out between multiple masts, allowing for a powerful sail surface, and a good repartition of efforts. The rig allows for good sailing into the wind. The Great Treasure Ships had 9 Masts on them and they were spread-out down each side of the ship to catch as much breeze as they could.

Also I found an interesting comment about the flags on the ships! This will be great for when we design our own ship. Flags were also hung from the masts to bring good luck and women to the sailors on board. A legend among the Chinese during the junk's heyday regarded a dragon which lived in the clouds. It was said that when the dragon became angry, it created typhoons and storms. Bright flags, with Chinese writing on them, were said to please the dragon. Red was the best color, as it would make the dragon likely to help the sailors.