Zeerover
19.05.2021 18:00:15
Attached to the mast at right angles to it is a straight piece of metal called the boom. more
See full version: Beginner Nautical terms
Attached to the mast at right angles to it is a straight piece of metal called the boom. more
Usually before there is any tension on it you only put one full turn on it and then pull like crazy until there is tension on it.
Once it is too much for your arms alone, turn the winch handle anticlockwise and this will use the mechanics inside the winch to help you tighten it the rest of the way.
Between the tack and the clew is the foot of the sail, and this is tightened by the jib sheets. When sailing you want the jib sheets just tight enough to keep the sail firm, yet by letting it out just a little bit it will flap. In setting it just right you get the most efficiency of the sail. more
Structures of the balance system inside the inner ear
Within the labyrinth are structures known as semicircular canals. The semicircular canals contain three fluid-filled ducts, which form loops arranged roughly at right angles to one another. They tell your brain when your head rotates. Inside each canal is a gelatin-like structure called the cupula [KEW-pyew-lah], stretched like a thick sail that blocks off one end of each canal. The cupula sits on a cluster of sensory hair cells. Each hair cell has tiny, thin extensions called stereocilia that protrude into the cupula.
When the signals from any of these sensory systems malfunction, you can have problems with your sense of balance, including dizziness or vertigo. If you have additional problems with motor control, such as weakness, slowness, tremor, or rigidity, you can lose your ability to recover properly from imbalance. This raises the risk of falling and injury. more
Posturography measures how well you can maintain steady balance during different platform conditions, such as standing on an unfixed, movable surface. Other tests, such as rotational chair testing, brisk head-shaking testing, or even tests that measure eye or neck muscle responses to brief clicks of sound, may also be performed. The vestibular system is complex, so multiple tests may be needed to best evaluate the cause of your balance problem. here
Many thanks to people who have pointed out new words, mistakes, or alternate meanings. here
Reading about small boats sometimes feels like reading a foreign language. This page is intended as a cheat sheet for non experts trying to understand more about small boats.
If you want me to add a word, or you know another meaning let me know. It's interesting that many nautical terms differ in meaning depending where you live. here
I decided to start with the hull terms. Mainly because I've been reading Chapelle and Gardiner, and I'm finding it quite hard going. It's not that the information is difficult to understand, it's just that the vocabulary is new to me.
I'm not planning to write a dictionary, just clarify enough boat words to make it possible to follow the gist of what these old fellers are talking about when they describe the traditional boats.
The hull is the main body of the ship below the main outside deck. The hull consists of an outside covering (or skin) and an inside framework to which the skin is secured. The skin and framework are usually made of steel and secured by welding. However, there may still be some areas where rivets are used. The steel skin may also be called shell plating. The main centerline structural part of the hull is the keel, which runs from the stem at the bow to the sternpost at the stern. The keel is the backbone of the ship. To the keel are fastened the frames, which run athwartship. These are the ribs of the ship and gives shape and strength to the hull. Deck beams and bulkheads support the decks and gives added strength to resist the pressure of the water on the sides of the hull.
Construction of a Hull SKIN The skin, or shell plating, provides water-tightness. The plates, the principal strength members of a ship, have various thickness. The heaviest plates are put on amidships. The others are put on so that they taper toward both ends of the ship (from the keel toward the bilge and from the bilge toward the upper row of plates). Using plates of various thickness reduces the weight of the metal used and gives the vessel additional strength at its broadest part. The plates, put on in rows from bow to stern, are called strakes. They are lettered consecutively, beginning at the keel and going upward. STRAKE NAMES The bottom row of strakes on either side of the keel, are called garboard strakes. The strakes at the turn of the hull, running in the bilge, are bilge strakes. The strakes running between the garboard and bilge strakes are called bottom strakes and the topmost strakes of the hull are sheer strakes. The upper edge of the sheer strake is the gunwale. BULKHEADS The interior of the ship is divided by the bulkheads and decks into watertight compartments. A vessel could be made virtually unsinkable if it were divided into enough small compartments. However, too many compartments would interfere with the arrangement of mechanical equipment and the operation of the ship. Engine rooms must be large enough to accommodate bulky machinery. Cargo spaces must be large enough to hold large equipment and containers.
Bulkheads and Decks ENGINE ROOM The engine room is a separate compartment containing the propulsion machinery of the vessel. Depending on the size and type of propulsion machinery, other vessel machinery may be located there (such as generators, pumping systems, evaporators, and condensers for making fresh water). The propulsion unit for Army vessels is a diesel engine. The "shaft" or rod that transmits power from the engine to the propeller leads from the aft end of the engine to the propeller. EXTERNAL PARTS OF THE HULL The waterline is the water-level line on the hull when afloat. The vertical distance from the waterline to the edge of the lowest outside deck is called the freeboard. The vertical distance from the waterline to the bottom of the keel is called the draft. The waterline, draft, and freeboard will change with the weight of the cargo and provisions carried by the ship. The draft of the ship is measured in feet and inches. Numbered scales are painted on the side of the ship at the bow and stern.
External Parts of the Hull The relationship between the drafts at the bow and stern is the trim. When a ship is properly balanced fore and aft, she is in trim. When a ship is drawing more water forward than aft, she is down by the head. If the stern is too far down in the water, she is down by the stern. If the vessel is out of balance laterally or athwartship (leaning to one side) she has a list. She may be listing to starboard or listing to port. Both trim and list can be adjusted by shifting the weight of the cargo or transferring the ship�s fuel and water from one tank to another in various parts of the hull. The part of the bow structure above the waterline is the prow. The general area in the forward part of the ship is the forecastle. Along the edges of the weather deck from bow to stern are removable stanchions and light wire ropes, called life lines. Extensions of the shell plating above the deck are called bulwarks. The small drains on the deck are scuppers. The uppermost deck running from the bow to the stern is called the weather deck. The main deck area over the stern is called the fantail or poop deck. The flat part of the bottom of the ship is called the bilge. The curved section where the bottom meets the side is called the turn of the bilge. Below the waterline are the propellers or screws which drive the ship through the water. The propellers are attached to and are turned by the propeller shafts. A ship with only one propeller is called a single-screw ship. Ships with two propellers are called twin-screw ships. On some ships (especially landing craft) there may be metal frames built around the propellers (called propeller guards) to protect them from damage. The rudder is used to steer the ship. NAMES OF DECKS The decks aboard ship are the same as the floors in a house. The main deck is the first continuous watertight deck that runs from the bow to the stern. In many instances, the weather deck and the main deck may be one and the same. Any partial deck above the main deck is named according to its location on the ship. At the bow it is called a forecastle deck, amidships it is an upper deck, and at the stern it is called the poop deck. The term weather deck includes all parts of the forecastle, main, upper, and poop decks exposed to the weather. Any structure built above the weather deck is called superstructure.
Weather Decks SHIPBOARD DIRECTIONS AND LOCATIONS The front end of the ship is the bow. When you move toward the bow, you are going forward, when the vessel is moving forward, it is going ahead. When facing toward the bow, the front-right side is the starboard bow and the front-left side is the port bow. The central or middle area of a ship is amidships. The right center side is the starboard beam and the left center side is the port beam. The rear of a vessel is the stern. When you move in that direction you are going aft, when the ship moves in that direction it is going astern. When looking forward, the right-rear section is called the starboard quarter and the left-rear section is called the port quarter. The entire right side of a vessel from bow to stern is the starboard side and the left side is the port side. A line, or anything else, running parallel to the longitudinal axis or centerline of the vessel is said to be fore and aft and its counterpart, running from side to side, is athwartships. From the centerline of the ship toward either port or starboard side is outboard and from either side toward the centerline is inboard. However, there is a variation in the use of outboard and inboard when a ship is on berth (moored to a pier). The side against the pier is referred to as being inboard; the side away from the pier as outboard.
Locations and Directions Aboard Ship How a Ship is Compartmented and Numbered Knowing how a ship is compartmented is crucial for navigating its vast interior. Each compartment of the ship is stamped with a series of alphanumeric numbers, known as "bull�s-eyes," which give information on where you are, and what that compartment�s function is. The information is given in the following order: deck number, frame number, relation to the centerline of the ship, and compartment usage. Each of these parts is separated by a hyphen. Decks above the main deck are numbered 01, 02, 03, etc. and are referred to as levels. Below the main deck, there are the first, second, third decks, etc. (remember, on a carrier the hangar deck, the one below the flight deck, is the main deck.). Frame numbers tell you where you are in relation to the bow of the ship; the numbers increase as you go aft. The third number in the bull�s-eye reflects compartmentation numbers in relation to the ship�s centerline. EVEN numbers are to PORT, and ODD numbers are to STARBOARD. The numbers increase as you travel outboard. The last letter stamped on the compartmentation number indicates what the compartment is used for. Below are some typical codes: Carrier Compartment Usage Codes
Figure 1.1. Carrier Deck Schematic [links]
Example Bull’s-eye: 3-75-4-M [links]
Understanding the events of December 7, 1941 doesn’t require you to be an expert in naval or technical terminology. The memorials, museums, and other attractions provide a historical overview of the attack on Pearl Harbor, and the things you need to know, such as the names and fates of the many ships that were there that morning, will be explained to you on your tour. If you like to have a little more in-depth knowledge, however, and prefer to understand some of the more technical terms you may hear, there are a few that are helpful to know. For example, what does it mean when we say that a ship is listing?
As a ship lists, for example when it’s caused by an explosion that tears a hole in the hull and allows water to rush in, weight is shifted toward the listing side. The left side of Oklahoma’s hull began taking on water, causing her list to become gradually worse. When another series of torpedoes struck her, she completely capsized and would have turned completely upside-down if not for her masts striking the harbor floor.
Another battleship that found itself listing to her port side was USS West Virginia (BB-48). Unlike Oklahoma, however, the crew of West Virginia were able to employ the tactic of counter-flooding to prevent her from listing further and capsizing.