What makes a ketch a ketch
A ketch has two masts. The forward one, the mainmast, is the taller. The second, the mizzenmast, is shorter and stands behind it, but forward of the rudder post. That last detail is the standard rule of thumb for telling a ketch from a yawl, whose mizzen stands aft of the rudder post. The mizzen of a ketch is also usually larger than a yawl’s, so it contributes more to the boat’s driving power.
These definitions are conventions, not laws. In practice, boats close to the dividing line are called one or the other depending on the person, the period and the country. Some authorities use the position of the rudder stock, or the steering position, or the proportion of the sail area, so a vessel with a mizzen right at the stern can reasonably be described either way.
An old arrangement under a changing name
Two-masted sailing vessels with a smaller mast aft are very old. In northern Europe, fore-and-aft and mixed rigs were common on coastal craft by the seventeenth century. The name “ketch” appears in English in that period, apparently derived from the older word “catch”, though the details of the term’s history are uncertain. Over time, “ketch” came to refer to a fairly specific rig, while the hulls underneath varied widely.
Earlier two-masted vessels were not always fore-and-aft. Square-rigged versions existed, and a number of ketches in the seventeenth and eighteenth centuries carried a mix of square and fore-and-aft sails, with a square topsail on the main. Over the eighteenth and nineteenth centuries the rig became more strongly fore-and-aft, partly because fore-and-aft sails needed fewer crew and handled well close to the wind.
The parts of the rig
Because “ketch” describes a layout, the sails themselves can take several forms. The most typical arrangement includes:
- A mainsail on the taller mast, either gaff-rigged with a four-sided sail and a spar at the top, or Bermuda-rigged with a triangular sail.
- A mizzen on the shorter mast, usually of the same general kind as the mainsail.
- One or more headsails forward of the mainmast, often set on a bowsprit on older boats.
- A topsail above the gaff on traditional rigs, often a small triangular or square sail added in light winds.
- A mizzen staysail set between the masts on a reach.
The mainmast on a ketch usually sits farther forward than the single mast of a sloop of comparable size. That keeps the centre of effort of the sails roughly where it should be for balance, once the mizzen is added behind it.
How the rig behaves
The two-masted layout offers a number of qualities that sailors have noticed through the centuries. These are general tendencies and depend heavily on the design of the individual boat.
- Balance in reduced sail. If the mainsail is lowered, the mizzen and headsail can be set against each other, which often keeps the boat balanced and manageable.
- Easier sails. The sail area is divided, so each sail is smaller than a single sail of equal total area.
- Less upwind efficiency. The mizzen is partly blanketed by the mainsail, so a ketch does not generally point as high or sail as fast to windward as a well-designed sloop.
- Extra gear. Two masts bring more stays, more halyards and more things to maintain.
For this reason, ketches have usually been favoured where handiness, strength and ease of sail handling mattered more than racing speed.
Gaff and Bermuda ketches
Traditional ketches were gaff-rigged. Their sails were supported by wooden spars that could be raised and lowered from the deck, and their rigging was typically made of hemp and later wire. Fishing boats, trading vessels and many pilot craft used this form. Brixham trawlers, among other fishing boats, are among the best-known examples of working ketch rigs in British waters.
The Bermuda or Marconi rig, adopted widely on yachts in the twentieth century, made the ketch rig lighter and tidier. With tall triangular sails, the mizzen was easier to build and to handle. This is the form of the ketch usually seen on modern cruising yachts, where the rig may be combined with roller-furling gear.
Related rigs
Three neighbouring rigs are often confused with the ketch.
- The yawl has its mizzen aft of the rudder post and usually much smaller.
- The schooner has two masts too, but the foremast is shorter than the aft mast, or equal to it, which is the opposite of a ketch.
- The sloop and cutter have a single mast.
Seen from a distance, a ketch and a yawl can look similar, and many yachts of the nineteenth and early twentieth century were converted from one to the other as owners tried different arrangements. Some of the changes were driven by racing rules, which could favour or penalise the mizzen depending on the period.
A flexible arrangement
The ketch is best seen as a family of related sail plans rather than a single fixed design. It served coastal traders, fishermen, bomb vessels and later cruising sailors, each time with a different hull and sail combination. What the layout offered was a way of dividing sail area that suited vessels worked by small crews, which explains why it lasted for several centuries in so many different settings.