Stern - Transom Stern

Transom Stern

In naval architecture, the term "transom" has two meanings. First, a transom can refer to any of the individual beams that run side-to-side or "athwart" the hull at any point abaft the fashion timber; second, a transom can refer specifically to the flat or slightly curved surface that is the very back panel of a transom stern. In this sense, a transom stern is the product of the use of a series of transoms, and hence the two terms have blended.

The stern of a classical sailing ship housed the captain's quarters and became increasingly large and elaborate between the 15th and 18th centuries, especially in the baroque era, when such wedding-cake-like structures became so heavy that crews sometimes threw the decoration overboard rather than be burdened with its useless weight. But until a new form of stern appeared in the 19th century, the transom stern was a floating house—and required just as many timbers, walls, windows, and frames. The stern frame provided the foundational structure of the transom stern, and was composed of the sternpost, wing transom, and fashion piece.

Abaft the fashion timber, the transom stern was composed of two different kinds of timbers:

• Transoms – These timbers extend across the low parts of the hull near the rudder, and are secured (either notched and/or bolted) to the sternpost. The transom located at the base of the stern, and the uppermost of the main transoms, was typically called the wing transom; the principal transom below this and level with the lower deck was called the deck transom; between these two were a series of filling transoms. If the stern had transoms above the wing transom, they would no longer be affixed to the sternpost. The first of these might be called a counter transom; next up was the window sill transom; above that, the spar deck transom. The larger the vessel, the more numerous and wider the transoms required to support its stern.
• Stern timbers (also called stern frames) – These timbers are mounted vertically in a series; each timber typically rests or "steps" on the wing transom and then stretches out (aft) and upward. Those not reaching all the way to the taffrail are called short stern timbers, while those that do are called long stern timbers. The two outermost of these timbers, located at the corners of the stern, are called the side-counter timbers or outer stern timbers. It is the stern timbers collectively which give a square stern its rake.

The flat surface of any transom stern may begin either at or above the waterline of the vessel. The geometric line which stretches from the wing transom to the archboard is called the counter; a large vessel may have two such counters, called a lower counter and a second or upper counter. The lower counter stretches from directly above the wing transom to the lower counter rail, and the upper counter from the lower counter rail to the upper counter rail, immediately under the stern's lowest set of windows (called "lights").