Ketch

A ketch is a sailing craft with two masts. The distinguishing characteristic of a ketch (ketamina) is that the forward of the two masts (the "mainmast") is larger than the after mast (the "mizzen"). Historically the ketch was a square-rigged vessel, most commonly used as a freighter or fishing boat in northern Europe, particularly in the Baltic and North seas. In modern usage, the ketch is a fore-and-aft rigged vessel used as a yacht or pleasure craft.

To assist going to windward, a ketch may carry one or more jibs or foresails. If a ketch has no jibs, it is called a cat ketch or a periauger. On older, larger ketches the main mast may in addition carry one or more square rigged topsails.

The large fore-and-aft sail on the mainmast is the mainsail, while the sail on the mizzen mast is the mizzen. These sails may be any type of fore-and-aft sail, in any combination. Most modern ketches are Bermuda rigged, but other possible rigs on a ketch include gunter rigs and gaff rigs. The Scots Zulu, for example, had a dipping lug main with a standing lug mizzen.

In northern Europe and among long distance cruisers, the ketch is often preferred to a sloop, since the additional sail allows a better balance, and a smaller more easily handled mainsail. An advantage of the ketch is when sudden increases in wind strength require a rapid reefing: the mainsail can be dropped, reducing sail and leaving a balanced sail-plan with jib and mizzen set. The ketch rig also allows sailing only on the mizzen and jib, without introducing excessive lee helm, and in an emergency can be quite well steered without use of the rudder. When running before the wind or reaching across the wind, a ketch may set extra sails such as a spinnaker on the main mast, and a spinnaker or mizzen staysail on the mizzen mast. Another advantage of a ketch is at anchor, where the mizzen sail may be used to hold the boat steady in the wind; this reduces roll in an otherwise uncomfortable anchorage.

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