Sunday, September 28, 2008

How Sailing Ships Works

Introduction:

Sailing began as a way to explore the world. While today's sailors still retain the bold spirit of explorers from centuries past, sailing is no longer a primary means of transportation and international trade or method of war. Since the 17th century, people have been setting sail for adventure and sport.

Racing yacht.
Jeff Randall/Taxi/Getty Images
Crew members on a racing yacht brace themselves to stay on the boat.

Most modern sailors sail because they love being on the water. Sailing is ranked as the 17th fastest-growing sport in the U.S., and it's estimated that more than 4 million Americans are recreational sailors [source: The Boating Channel]. The appeal of sailing is ageless: 40 percent of sailors are between the ages of 25 to 44, and roughly 17 percent are younger than age 17 [source: The Boating Channel].

So whether you're inspired by famous explorers such as Amerigo Vespucci or Vasco Da Gama, the winners of the America's Cup sailing races, or you just love the feel of wind in your hair, sailing is a sport to sate your adventurous side. Fair winds!

Types of Recreational Sailing

If you're looking for a little fun and some high-seas adventure, there are some popular types of recreational sailing that may suit you. If you're looking for something a little different, we have a few unconventional suggestions, too.

If you're a sailing novice, you might want to start out with small sailboats like dinghies, daysailers and small keelboats. They're easy to maneuver, are usually less than 25 feet in length. These can be sailed by an individual (solo sailing) or with one crewmember [source: U.S. Sailing]. Some sailors begin with small sailboats and continue adventuring this way even as they become experts. Dinghies are fun and lightweight -- they're used by college racing teams and in the Olympics, and they're perfect for weekend warriors.

Dinghies.
Chris Jackson/Getty Images
A fleet of 50 Enterprise dinghies sails down the Thames past Chelsea Bridge and Battersea Power Station in London.

Some adventurers, though, take their sailing hobby to a whole new level and go cruising. Cruising isn't a just a hobby; it's a lifestyle. When you hear about someone who is sailing around the world, they're cruising. Sailors who choose cruising live on their sailboats and travel for extended periods of time. Their vessels range from basic keelboats to large, multi-hull cruising yachts. Most boats intended for cruising have many of the comforts of home below deck, and depending on their size, may include beds, bathrooms, kitchen facilities and even entertainment systems.

For those who want the adventure or relaxation of sailing without the work, boats can be chartered with skippers, and yachts can be chartered with crews. Two popular types of family-friendly chartered sailing adventures are sunset cruises and Caribbean sailing vacations. Sunset cruises are leisurely sailing experiences and are typically chartered by small groups looking to relax. If sailing in the Caribbean like the rich and famous sounds more like your style, boats (with or without hired crews) may be chartered through travel agencies. Some popular island destinations for Caribbean sailors include the Virgin Islands, Antigua, St. Barts, St. Martin and Grenada.

Basic Sailing Skills and Terms

The basics of sailing are easy to learn in a few classes, although it can take a lifetime to perfect them. Of the many skills and techniques to learn about sailing, there are five essentials: sail setting, boat balance, fore and aft trim, position of the centerboard, and course made good.

Racing yacht.
Ryan McVay/Allsport Concepts
The crew members of a racing yacht are sure to know the five basics of sailing.

  1. Sail setting: Sailboats can't be taken directly into the wind or they run the risk of stopping (when there's literally no wind in your sails). Depending on your point of sail -- the direction of your boat in relation to the direction of the wind -- different sail settings are needed. You can set your main sail by listening to it: Ease the sail out until it flaps along the luff, the part closest to the mast, and then pull it back in just until the flapping stops.
  1. Boat balance: When your boat begins to lean to one side, it's known as heeling. To overcome heeling and stay on course, it's important to stay aware of the wind (is it gusting?) and the position of your sails. Also keep aware of the weight you have onboard and how it's distributed. If your boat is leaning port side, you can counteract it by moving your weight (or the weight of the crew) to the opposite, or starboard, side.
  1. Fore and aft trim: A boat must also stay balanced from end-to-end. Generally, the front of a boat (bow) is raised slightly higher than the back (stern), and the distribution of body weight on board (you and your crew) is key to maintaining that balance. If you find your boat is dragging in the water (an example of what happens when the back of the boat is too low), move your weight closer to the middle or front of the boat. If the bow is submerging in the water, take a seat toward the back of the boat. A correctly balanced boat allows you to sail more quickly.
  1. Position of the centerboard: There is a delicate balance between your boat and the wind, and you can easily find yourself being pushed off course by it. The centerboard, a piece of wood, fiberglass or metal (depending on what your boat is made from), is a movable fin under the hull. By adjusting it in relation to your point of sail, you're able to correct any drift.
  1. Course made good: Getting from point A to point B isn't always a straight course, especially if the straight course takes you directly into the wind. Planning a route that gets you to your destination in the shortest possible time is called "course made good." This is generally accomplished through a maneuver called tacking, in which the boat is steered in a zigzag, upwind direction.

To find a sailing school in the United States, visit the American Sailing Association.

Knot Knowledge
Sailors know their knots. There are two general types you should know: bend and hitch. A bend is a knot that fastens rope ends together. A hitch loops a rope around itself to secure the boat to a rail or post.

There are hundreds of knots but only a few basics that should be on your practice list:

  • Bowline: A bowline knot is your standby. It creates a loop at the end of a top, is strong and easy to untie. If you know the old saying, the rabbit comes out of his hole, 'round the tree and back down into his hole, you already know the bowline. When in doubt, use this knot.
  • Square knot: The square knot, or reef knot, is used to tie two ropes (lines) of the same size together. You may be familiar with it from Boy Scouts or Girl Scouts, first-aid class or from tying your shoelaces.
  • Clove hitch: This loop is a quick way to temporarily moor a small boat to a ring, rail or post.
  • ­Round turn and two half hitches: This knot is frequently used to secure a boat to the docking ring or post.
  • Figure-of-eight: This stopper knot is used to prevent a rope from unraveling or slipping out of a ring or other device. This type of knot is essential in both sailing and rock climbing.
  • Sheet bend: Need a longer rope? A sheet bend knot is a quick way to fasten two lines temporarily.

    Sailing Safety and Regulations

    To keep recreational sailing a fun and safe activity, there are some rules sailors are expected to follow. First, it's important to be honest about your skill level. Don't overextend yourself -- if you're a beginner or an old pro, going beyond your skill puts both you and others at risk. According to the U.S. Coast Guard, 70 percent of reported deaths at sea occur because the boat operator didn't have adequate (or any) boating instruction [source: U.S. Coast Guard].

    Yachts
    Peter Mumford/Beken/Kos Picture Source via Getty Images
    Sailors need to pay attention to the weather forecast so they don't get caught in a sudden squall. These yachts are competing in the J109 UK National Championships.

    Your skills will only take you so far -- you'll need wind in your sails to get you out on the water. Make sure to determine the wind speed and direction before you set out. Also check the forecast. It may be sunny as you make your preparations, but a change in the weather could result in a dangerous expedition.

    Sailboat Racing
    As their sailing skills improve, many sailors enjoy testing their techniques, strategies and tactics in races. Races are organized by sailing clubs and schools around the world. There are two types of sailboat races: team racing (or fleet racing) where two to four boats compete together, and match racing, where two boats compete head to head.

    One of the most famous two-boat races is the America's Cup, in which the best sailors, engineers and boat builders get to show off their skills. The rules -- known as the Racing Rules of Sailing -- are established by the International Sailing Federation (ISAF) and are published every four years. Visit the ISAF to download a copy of the Racing Rules of Sailing.

    With skill level and wind direction determined, you'll also want to inspect your boat, gear and tools to ensure they're all in good condition, and note if you have everything you need onboard before setting out. Federal law requires you to carry safety equipment onboard. You and your crew should wear life jackets and all know how to use the boat's safety equipment. Be sure to know how to make a distress call for immediate assistance -- the time you find yourself in trouble is not the time to figure how to call for help.

    It's also smart to have a plan. On your adventure you'll likely be out of sight of land, and if you have an emergency, it might be difficult for help to find you. Put together a float plan and leave a copy with a friend or local marina before you set sail. At the least, your plan should include:

  • A description of your boat
  • The name of your boat operator and the names of all people onboard
  • What type of safety and survival equipment you have with you (food, flares, paddles, marine radios, etc.)
  • Your destination, arrival and departure times

Skill, wind, inspection and a plan -- check. Once you've launched your boat, be alert and aware of your surroundings. By simply maintaining a safe speed and looking around you, you're less likely to collide with other boats or objects (the top two causes of accidents [source: U.S. Coast Guard]). And leave the alcohol on shore: Drinking and operating equipment is just as dangerous at sea as it is on the roads. Violators with a blood alcohol content of .08 percent or higher may be subject to civil and criminal penalties, one year imprisonment or both. [source: U.S. Coast Guard]. Alcohol use is a leading factor in fatal boating accidents -- nearly 20 percent of reported fatalities [source: U.S. Coast Guard].

For a comprehensive list of rules and regulations, visit the U.S. Coast Guard's Navigation Center.

Boating Superstitions

If you're smart and follow basic sailing regulations, you should be able to stay safe on your expedition. But sailors are a superstitious bunch and have many nautical myths:

  • Whistling: It's a universal sailing superstition that whistling onboard will surely whip up the winds, thus the saying "whistling up a storm."
  • Earrings: Some sailors believe they cannot drown if they wear earrings.
  • Lefties: It's said sailors would never step on or off a boat leading with the left foot, fearing bad luck. This is a type of sinistrophobia, the fear of things on the left side of the body, and of south-paws.
  • Animals: Superstitions surrounding animals abound. Black cats are good omens, as are dolphins. But watch out for sharks; they're rumored to spell doom.
  • The Flying Dutchman: The Flying Dutchman is a ghost ship, and as legend goes, its appearance signals imminent danger or death to those who see it.
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Air Craft Carrier


An aircraft carrier is a warship designed with a primary mission of deploying and recovering aircraft, acting as a sea-going airbase. Aircraft carriers thus allow a naval force to project air power great distances without having to depend on local bases for staging aircraft operations. They have evolved from wooden vessels used to deploy a balloon into nuclear powered warships that carry dozens of fixed and rotary wing aircraft.
Balloon carriers were the first ships to deploy manned aircraft, used during the 19th and early 20th century, mainly for observation purposes. The 1903 advent of fixed wing airplanes was followed in 1910 by the first flight of such an aircraft from the deck of a US Navy cruiser. Seaplanes and seaplane tender support ships, such as HMS Engadine, followed. The development of flat top vessels produced the first large fleet ships. This evolution was well underway by the mid 1920s, resulting in ships such as the HMS Hermes, Hōshō, and the Lexington class aircraft carriers.
World War II saw the first large scale use and further refinement of the aircraft carrier, spawning several types. Escort aircraft carriers, such as USS Barnes, were built only during World War II. Although some were purpose built, most were converted from merchant ships, and were a stop-gap measure in order to provide air support for convoys and amphibious invasions. Light aircraft carriers, such as USS Independence represented a larger, more "militarized" version of the escort carrier concept. Although the light carriers usually carried the same size air groups as escort carriers, they had the advantage of higher speed as they had been converted from cruisers under construction rather than civilian merchant ships.
Wartime emergencies also saw the creation or conversion of other, unconventional aircraft carriers. CAM ships, like the SS Michael E, were cargo carrying merchant ships which could launch but not retrieve fighter aircraft from a catapult. These vessels were an emergency measure during World War II as were Merchant aircraft carriers (MACs), such as Mv Empire MacAlpine, another emergency measure which saw cargo-carrying merchant ships equipped with flight decks. Battlecarriers were created by the Imperial JapaneseNavy to partially compensate for the loss of carrier strength at Midway.
Two of them were made from Ise class battleships during late 1943. The aft turrets were removed and replaced with a hangar, deck and catapult. The heavy cruiser Mogami concurrently received a similar conversion. This "half and half" design was an unsuccessful compromise, being neither one thing nor the other. Submarine aircraft carriers, such as the French Surcouf, or the Japaneseclass I-400 submarines, which were capable of carrying 3 Aichi M6A Seiran aircraft, were first built in the 1920s, but were generally unsuccessful at war. Modern navies that operate such ships treat aircraft carriers as the capital ship of the fleet, a role previously played by the battleship. The change, part of the growth of air power as a significant part of warfare, took place during World War II. This change was driven by the superior range, flexibility and effectiveness of carrier-launched aircraft.
Following the war, the scope of carrier operations continued to increase in size and importance. Supercarriers, typically displacing 75,000 tonnes or greater, have become the pinnacle of carrier development. Most are powered by nuclear reactors and form the core of a fleet designed to operate far from home. Amphibious assault ships, such as USS Tarawa or HMS Ocean, serve the purpose of carrying and landing Marines and operate a large contingent of helicopters for that purpose. Also known as "commando carriers" or "helicopter carriers", they have a secondary capability to operate VSTOL aircraft.
Lacking the firepower of other warships, carriers by themselves are considered vulnerable to attack by other ships, aircraft, submarines or missiles and therefore travel as part of a carrier battle group (CVBG) for their protection. Unlike other types of capital ships in the 20th century, aircraft carrier designs since World War II have been effectively unlimited by any consideration save budgetary, and the ships have increased in size to handle the larger aircraft: The large, modern Nimitz class of United States Navy carriers has a displacement nearly four times that of the World War II-era USS Enterprise yet its complement of aircraft is roughly the same, a consequence of the steadily increasing size of military aircraft over the years.

Air Craft Carrier-Architecture

Air Craft Carrier-Architecture

SUB MARINE

A submarine is a watercraft that can operate independently underwater, as distinct from a submersible that has only limited underwater capability. The term submarine most commonly refers to large manned autonomous vessels, however historically or more casually, submarine can also refer to medium sized or smaller vessels, (midget submarines, wet subs), Remotely Operated Vehicles or robots. The word submarine was originally an adjective meaning "under the sea", and so consequently other uses such as "submarine engineering" or "submarine cable" may not actually refer to submarines at all. Submarine was shortened from the term "submarine boat".
Submarines are referred to as "boats" for historical reasons because vessels deployed from a ship are referred to as boats. The first submarines were launched in such a manner. The English term U-Boat for a German submarine comes from the German word for submarine, U-Boot, itself an abbreviation for Unterseeboot ("undersea boat").
Although experimental submarines had been built before, submarine design took off during the 19th century. Submarines were first widely used in World War I, and feature in many large navies. Military usage ranges from attacking enemy ships or submarines, aircraft carrier protection, blockade running, ballistic missile submarines as part of a nuclear strike force, reconnaissance and covert insertion of special forces. Civilian uses for submarines include marine science, salvage, exploration and facility inspection/maintenance. Submarines can also be specialised to a function such as search and rescue, or undersea cable repair. Submarines are also used in tourism and for academic research.
Submarines have one of the largest ranges in capabilities of any vessel, ranging from small autonomous or one- or two-man vessels operating for a few hours, to vessels which can remain submerged for 6 months such as the Russian Typhoon class. Submarines can work at greater depths than are survivable or practical for human divers. Modern deep diving submarines are derived from the bathyscaphe, which in turn was an evolution of the diving bell.
Most large submarines comprise a cylindrical body with conical ends and a vertical structure, usually located amidships, which houses communications and sensing devices as well as periscopes. In modern submarines this structure is the "sail" in American usage ("fin" in European usage). A "conning tower" was a feature of earlier designs: a separate pressure hull above the main body of the boat that allowed the use of shorter periscopes. There is a propeller (or pump jet) at the rear and various hydrodynamic control fins as well as ballast tanks. Smaller, deep diving and specialty submarines may deviate significantly from this traditional layout.

SUB MARINE

SUB MARINE

SUB MARINE1

SUB MARINE1

SUB MARINE II

SUB MARINE II

Sailing Ships

Sailing ship is now used to refer to any large, wind-powered, vessel. In technical terms, a ship was a sailing vessel with a specific rig of at least three masts, square rigged on all of them, making the sailing adjective redundant. In popular usage ship became associated with all large sailing vessels and when steam power came along the adjective became necessary.
specification:
There are many different types of sailing ship, but they all have certain basic things in common. Every sailing ship has a hull, rigging and at least one mast to hold up the sails that use the wind to power the ship. The crew who sail a ship are called sailors or hands. They take turns to take the watch, the active managers of the ship and her performance for a period.
Watches are traditionally four hours long. Some sailing ships use traditional ship's bells to tell the time and regulate the watch system, with the bell being rung once for every half hour into the watch and rung eight times at watch end (a four-hour watch).
Ocean journeys by sailing ship can take many months, and a common hazard is becoming becalmed because of lack of wind, or being blown off course by severe storms or winds that do not allow progress in the desired direction. A severe storm could lead to shipwreck, and the loss of all hands.
Sailing ships can only carry a certain quantity of supplies in their hold, so they have to plan long voyages carefully to include many stops to take on provisions and, in the days before watermakers, fresh water.

SAILING SHIPS

SAILING SHIPS

Sailing Ships

Sailing Ships

FRIGATE CLASS SHIPS



Basically a frigate [frĭg'-ĭt] is a warship. The term has been used for warships of many sizes and roles over the past few centuries.
In the 18th century, the term referred to ships which were as long as a ship-of-the-line and were square-rigged on all three masts (full rigged), but were faster and with lighter armament, used for patrolling and escort. In the 19th century, the armoured frigate was a type of ironclad warship and for a time was the most powerful type of vessel afloat.
In modern navies, frigates are used to protect other warships and merchant-marine ships, especially as anti-submarine warfare(ASW) combatants for amphibious expeditionary forces, underway replenishment groups, and merchant convoys. But ship classes dubbed "frigates" have also more closely resembled corvettes, destroyers, cruisers and even battleships.

INS GOTHAVARI

INS GOTHAVARI

INS GOTHAVARI

TYPE 16 GODAVARI CLASS:

Vessel Type:
Guided Missile Frigate.
Names & Pennant Numbers with commission dates:
Godavari F20 (10 December 1983) INS Ganga F22 (30 December 1985)INS Gomati F21(16 April 1988)
Structure:
The Type 16 Class frigates are a modification of the original Leander Class design with an indigenous content of 72% and a larger hull.
Displacement:
3600 tons standard.............3850 tons full load.
Dimensions:
Length - 126.4 metres.................Beam - 14.5 metres.................Draught - 4.5 metres.
Main Machinery:
Two turbines with 30,000 hp motors, two 550 psi boilers and two shafts.
Maximum Speed: 27 knots.
Maximum Range: 4500 miles at 12 knots.
Complement:
313 (incl. 40 Officers & 13 Aircrew).
Radar:
Air; One Signaal radar at D-band frequency (range - 145n miles; 264 km).........Air/Surface; One MR-310U Angara (NATO: Head Net-C) radar at E-band frequency (range - 70n miles; 128 km)..........Navigation/Helo Ctrl; Two Signaal ZW06 or Don Kay radars at I-band frequency..........Fire Control; Refer to 'Weapons' sub-section.
Sonar: The Bharat APSOH; hull mounted and provides active panoramic search & attack with medium frequency. The vessels also have a Fathoms Oceanic VDS (Variable Depth Sonar) and Type 162M sonar, which provides bottom classification with high frequency. INS Ganga has a Thomson Sintra DSBV 62; passive towed array sonar with very low frequency.
Weapons:
Four P-20M (SS-N-2D Styx) AShMs, fitted in single-tube launchers, with active radar (Mod 1) or infra-red (Mod 2) homing to 45n miles; 83 km at 0.9 Mach. Becomes a sea skimmer at the end of run. Has a 513 kg warhead.
INS Ganga and INS Gomati have been refitted with the Israeli Barak SAM system, with fire control provided by an EL/M-2221 STG radar.
The latter vessel was first sighted with the Barak in December 2002 and the system was reportedly operational by March 2003. It is probable that INS Godavari also has the Barak system, but that is yet to be confirmed through official channels. Prior to the fitment of the Barak system, these vessels had a single vertical launcher with the OSA-M (SA-N-4) SAM with SAR homing to 8n miles; 15 km at Mach 2.5, with a service ceiling of 3048 meters and a 50 kg warhead. A total of 20 OSA-M missiles were carried on board and they had a limited SSM capability. Fire control was provided by a single MPZ-310 (NATO: Pop Group) radar at F/H/I-band frequency, which has since been removed from the vessels that feature the Barak system.
Two 57mm (twin) guns at 90º elevation, 120 rds/min to 4.4n miles; 8 km, for use against ship- and shore-based targets. Fire control is provided by a single MR-103 (NATO: Muff Cob) radar at G/H-band frequency. In the CIWS role, the vessels are fitted with four AK-230 30mm gunmounts with 85º elevation and 500 rounds/min to 2.7n miles; 5 km with fire control provided by two MR-123 (NATO: Drum Tilt) radars at H/I-band frequency.
Features six 324mm ILAS 3 (2 triple) torpedo tubes, which fire the Whitehead A244S anti-submarine torpedo which has active/passive homing to 3.8n miles; 7 km at 33 knots with a 34 kg shaped charged warhead. INS Godavari has tube modifications for the Indian NST 58 version of A244S.
Weapons Control:
MR 301 MFCS and MR 103 GFCS.
Combat Data System: Selenia IPN-10 action data automation and a Immarsat communications (JRC) system.
Helicopters:
Two Sea King Mk.42B or a combination of one Sea King Mk.42B and one HAL Chetak. Usually one helicopter is carried with more than one air crew. French Samahé helicopter landing equipment is fitted. The Naval ALH can also be embarked.
Countermeasures:
Selenia INS-3 (Bharat Ajanta and Elettronica TQN-2) intercept and jammer is used for ESM/ECM purposes. Two chaff/flares are used as decoys. Will have the 'Super Barricade' decoys in due course. Also has a Graesby G738 towed torpedo decoy.