The sail-plan of a junk differs from that of tra

The sail-plan of a junk differs from that of traditional square-rigged ships, with the junk’s various sails capable of being moved inwards towards the ship’s lengthy central axis, allowing it to be easily modified in order to sail into the wind. The sails themselves also differ from the traditional variety, with long horizontal struts called battens providing a rigid shape – akin to that of Venetian blinds – and greater tear-resistance in high wind. Further increasing the power and speed of a junk is its tendency to spread its sails over multiple masts, with five or more common on larger vessels.
Junk hulls were traditionally constructed from softwoods such as cedar and sported a horseshoeshaped stern, elevated poop deck and flat base with no keel. Due to this, junk hulls are fitted with an overly large keel and series of lee and centreboards (lifting foils) to remain stable. Hulls were also strengthened greatly by multiple partitioning lengthways and sideways internally, creating a series of interior compartments. The addition of these matrix braces increased hull integrity – especially from sideways pressure – and also dramatically reduced flooding speed if breeched, with a series of limber holes (drainage holes) transferring water outside.