Stern
Encyclopedia
The stern is the rear or aft
Aft
Aft, in naval terminology, is an adjective or adverb meaning, towards the stern of the ship, when the frame of reference is within the ship. Example: "Able Seaman Smith; lay aft!". Or; "What's happening aft?"...

-most part of a ship
Ship
Since the end of the age of sail a ship has been any large buoyant marine vessel. Ships are generally distinguished from boats based on size and cargo or passenger capacity. Ships are used on lakes, seas, and rivers for a variety of activities, such as the transport of people or goods, fishing,...

 or boat
Boat
A boat is a watercraft of any size designed to float or plane, to provide passage across water. Usually this water will be inland or in protected coastal areas. However, boats such as the whaleboat were designed to be operated from a ship in an offshore environment. In naval terms, a boat is a...

, technically defined as the area built up over the sternpost
Sternpost
A sternpost is the upright structural member or post at the stern of a ship or a boat, to which are attached the transoms and the rearmost left corner part of the stern...

, extending upwards from the counter rail to the taffrail
Taffrail
A Taffrail is the aftermost railing around the stern of a ship, often, but not always, ornately carved. A taffrail log is an object dragged from the stern of the vessel to calculate the vessel's speed through the water...

. The stern lies opposite of the bow
Bow (ship)
The bow is a nautical term that refers to the forward part of the hull of a ship or boat, the point that is most forward when the vessel is underway. Both of the adjectives fore and forward mean towards the bow...

, the foremost part of a ship. Originally, the term only referred to the aft port section of the ship, but eventually came to refer to the entire back of a vessel. The stern end of a ship is indicated with a white navigation light
Navigation light
A navigation light is a colored source of illumination on an aircraft, spacecraft, or waterborne vessel, used to signal a craft's position, heading, and status...

 at night.

Sterns on European and American wooden sailing ships began with two principal forms: the square or transom stern and the elliptical, fantail, or merchant stern, and were developed in that order. The hull sections located before the stern are composed of a series of U-shaped rib-like frames set in a sloped or "cant" arrangement, with the last frame before the stern being called the fashion timber(s) or fashion piece(s), so called for "fashioning" the after part of the ship. This frame is designed to support the various beams that make up the stern.

In 1817 the British naval architect Sir Robert Seppings first introduced the concept of the round or "circular" stern. The square stern had been an easy target for enemy cannon, and could not support the weight of heavy stern chase gun
Chase gun
The chase guns, usually distinguished as bow chasers and stern chasers were cannons mounted in the bow or stern of a sailing ship...

s. But Seppings' design left the rudder head exposed, and was regarded by many as simply ugly—no American warships were designed with such sterns, and the round stern was quickly superseded by the elliptical stern. The United States began building the first elliptical stern warship in 1820, a decade before the British. The USS Brandywine
USS Brandywine (1825)
USS Brandywine was a wooden-hulled, three-masted Frigate of the United States Navy bearing 44 guns which had the initial task of conveying the Marquis de Lafayette back to France...

 became the first sailing ship to sport such a stern. Though a great improvement over the transom stern in terms of its vulnerability to attack when under fire, elliptical sterns still had obvious weaknesses which the next major stern development—the iron-hulled cruiser stern—addressed far better and with much different materials.

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
Baroque
The Baroque is a period and the style that used exaggerated motion and clear, easily interpreted detail to produce drama, tension, exuberance, and grandeur in sculpture, painting, literature, dance, and music...

 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 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
    Taffrail
    A Taffrail is the aftermost railing around the stern of a ship, often, but not always, ornately carved. A taffrail log is an object dragged from the stern of the vessel to calculate the vessel's speed through the water...

     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
    Rake
    Rake may refer to:* Rake , a horticultural implement, a long-handled tool with tines* Rake or hay rake, a farm implement* Rake or castor angle – various fork offset angles in bicycle and motorcycle geometry...

    .


The flat surface of any transom stern may begin either at or above the waterline
Waterline
The term "waterline" generally refers to the line where the hull of a ship meets the water surface. It is also the name of a special marking, also known as the national Load Line or Plimsoll Line, to be positioned amidships, that indicates the draft of the ship and the legal limit to which a ship...

 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").

Elliptical stern

The visual unpopularity of Seppings' circular stern was soon rectified by Sir William Symonds. In this revised stern, a set of straight post timbers (also called "whiskers", "horn timbers", or "fan tail timbers") stretches from the keel diagonally aft and upward. It rests on the top of the sternpost and runs on either side of the rudder post (thus creating the "helm port" through which the rudder passes) to a point well above the vessel's waterline. Whereas the timbers of the transom stern all heeled on the wing transom, the timbers of the elliptical stern all heel on the whiskers, to which they are affixed at a 45̊ angle (i.e., "canted") when viewed from overhead and decrease in length as they are installed aft until the curvature is complete. The finished stern has a continuous curved edge around the outside and is raked aft. Other names for the elliptical stern include a "counter stern," in reference to its very long counter, and a "cutaway stern." The elliptical stern began use during the age of sail
Age of Sail
The Age of Sail was the period in which international trade and naval warfare were dominated by sailing ships, lasting from the 16th to the mid 19th century...

, but remained very popular for both merchant and warships well into the nautical age of steam
Steamboat
A steamboat or steamship, sometimes called a steamer, is a ship in which the primary method of propulsion is steam power, typically driving propellers or paddlewheels...

 and through the first eight decades of steamship construction (roughly 1840–1920), despite the fact that the design left the rudder exposed and vulnerable in combat situations.

Cruiser stern

As ships of wooden construction gave way to iron and steel, the cruiser stern—another design without transoms and known variously as the canoe stern, parabolic stern, and the double-ended stern—became the next prominent development in ship stern design, particularly in warships of the latter half of the 20th century. The intent of this re-design was to protect the steering gear by bringing it below the armor deck. The stern now came to a point rather than a flat panel or a gentle curve, and the counter reached from the sternpost all the way to the taffrail in a continuous arch. It was soon discovered that vessels with cruiser sterns experienced less water resistance when under way than those with elliptical sterns, and between World War I and World War II most merchant ship designs soon followed suit.

None of these three main types of stern has vanished from the modern naval architectural repertoire, and all three continue to be utilized in one form or another by different sets of designers and for a broad spectrum of uses. Variations on these basic designs have resulted in a outflow of "new" stern types and names, only some of which are itemized here.

Other types of stern

The reverse stern, reverse transom stern, sugar-scoop, or retroussé stern is a kind of transom stern that is raked backwards (common on modern yachts, rare on vessels before the 20th century); the vertical transom stern or plumb stern is raked neither forward nor back, but falls directly from the taffrail down to the wing transom. The rocket ship stern is a term for an extremely angled retroussé stern. A ship with a very narrow round stern is said to have a pink stern or pinky stern. The torpedo stern or torpedo-boat stern describes a kind of stern with a low rounded shape that is nearly flat at the waterline, but which then slopes upward in a conical fashion towards the deck (practical for small high-speed power boats with very shallow drafts).

A Constanzi stern is a type of stern designed for use on ocean-going vessels. It is a compromise between the 'spoon-shaped' stern usually found on ocean liner
Ocean liner
An ocean liner is a ship designed to transport people from one seaport to another along regular long-distance maritime routes according to a schedule. Liners may also carry cargo or mail, and may sometimes be used for other purposes .Cargo vessels running to a schedule are sometimes referred to as...

s, and the flat transom, often required for fitting azimuth thruster
Azimuth thruster
An azimuth thruster is a configuration of ship propellers placed in pods that can be rotated in any horizontal direction, making a rudder unnecessary...

s. The design allows for improved seagoing characteristics. It is the stern design on Queen Mary 2
RMS Queen Mary 2
RMS Queen Mary 2 is a transatlantic ocean liner. She was the first major ocean liner built since in 1969, the vessel she succeeded as flagship of the Cunard Line....

, and was originally proposed for SS Oceanic and Eugenio C, both constructed in the 1960s. It is arguably one of the least aesthetically pleasing of stern designs.

A bustle stern refers to any kind of stern (transom, elliptical, etc.) that has a large "bustle" or blister at the waterline below the stern to prevent the stern from "squatting" when getting underway. It only appears in power-driven craft, never on sailing ships.
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