Ketch on San Francisco Bay

A ketch is a sailing craft with two masts: A main mast, and a mizzen mast abaft the main mast. Both masts are rigged mainly fore-and-aft. From one to three jibs are carried forward of the main mast when going to windward. On older, larger ketches the main mast may in addition carry one or more square rigged topsails, similar to a sloop. A ketch may also carry extras, see below.

The main fore-and-aft sail on the main mast is called the mainsail, while that on the mizzen is called the mizzen sail. These may be either gaff or bermuda rigged, or less often one of each in either combination.

The ketch rig is often confused with a yawl. The difference is that the ketch has her mizzen mast forward of the rudder post thus having more sail area, which contributes significant forward propulsion, whereas the mizzen on a yawl is aft of the rudder post and is used primarily to balance the sail plan (and as a riding sail while at anchor).

The ketch is popular among long distance cruisers as the additional sail allows for a better balance, and a smaller more easily handled mainsail for the same overall sail area. It also allows sailing on mizzen and jib only without introducing excessive lee helm, and in an emergency can be quite well steered without use of the rudder.

Running before the wind or reaching across the wind, a ketch may carry extra sails such as a spinnaker on the main mast, and possibly a second smaller reaching set between the masts (mizzen staysail).

See also sail-plan.

Other types of sailing vessels