68-529: Haganeyama Transmitter (はがね山標準電波送信所, haganeyama-hyoujyundenpa-soushinjyo ) is an LF -time signal transmitter at Fuji-cho, Saga-city , Saga-ken , Japan used for transmitting the time signal JJY on 60 kHz. The Haganeyama site is one of two JJY transmitters, another is the Otakadoyama site . Source: 33°27′56″N 130°10′34″E / 33.4656°N 130.176°E / 33.4656; 130.176 Low frequency Low frequency ( LF )
136-545: A limited and asymmetric nature. Naval warfare developed when humans first fought from water-borne vessels. Before the introduction of the cannon and ships with enough capacity to carry them, navy warfare primarily involved ramming and boarding actions. In the time of ancient Greece and the Roman Empire , naval warfare centered on long, narrow vessels powered by banks of oarsmen (such as triremes and quinqueremes ) designed to ram and sink enemy vessels or come alongside
204-489: A sister ship of Bismarck , was almost put out of action by miniature submarines known as X-Craft . The X-Craft severely damaged her and kept her in port for some months. A major paradigm shift in naval warfare occurred with the introduction of the aircraft carrier . First at Taranto in 1940 and then at Pearl Harbor in 1941, the carrier demonstrated its ability to strike decisively at enemy ships out of sight and range of surface vessels. The Battle of Leyte Gulf (1944)
272-466: A 2.8 kHz sliver of spectrum from 71.6 kHz to 74.4 kHz beginning in April ;1996 to UK amateurs who applied for a Notice of Variation to use the band on a noninterference basis with a maximum output power of 1 Watt ERP . This was withdrawn on 30 June 2003 after a number of extensions in favor of the cross-European standard 136 kHz band. Very slow Morse Code from G3AQC in
340-463: A built-in pre-amplifier . Due to the long wavelengths in the band, nearly all LF antennas are electrically short , shorter than one quarter of the radiated wavelength, so their low radiation resistance makes them inefficient, requiring very low resistance grounds and conductors to avoid dissipating transmitter power. These electrically short antennas need loading coils at the base of the antenna to bring them into resonance. Many antenna types, such as
408-786: A catastrophe for the Russian military in general and the Russian Navy in particular. Although neither party lacked courage, the Russians were defeated by the Japanese in the Battle of Port Arthur, which was the first time in warfare that mines were used for offensive purposes. The warships of the Baltic Fleet sent to the Far East were lost in the Battle of Tsushima. A further step change in naval firepower occurred when
476-404: A group, which may be a small squadron of comparable ships, or a larger naval fleet of various specialized ships. The commander of a fleet travels in the flagship , which is usually the most powerful vessel in the group. Before radio was invented, commands from the flagship were communicated by means of flags. At night signal lamps could be used for a similar purpose. Later these were replaced by
544-619: A height around 100 meters are used. T-antennas have a height between 50–200 meters, while mast aerials are usually taller than 150 meters. The height of mast antennas for LORAN-C is around 190 meters for transmitters with radiated power below 500 kW, and around 400 meters for transmitters greater than 1 000 kilowatts. The main type of LORAN-C antenna is insulated from ground. LF (longwave) broadcasting stations use mast antennas with heights of more than 150 meters or T-aerials . The mast antennas can be ground-fed insulated masts or upper-fed grounded masts. It
612-437: A large number of cannon made oar-based propulsion impossible, and ships came to rely primarily on sails . Warships were designed to carry increasing numbers of cannon and naval tactics evolved to bring a ship's firepower to bear in a broadside , with ships-of-the-line arranged in a line of battle . The development of large capacity, sail-powered ships carrying cannon led to a rapid expansion of European navies, especially
680-573: A major naval power in the mid-17th century in the first Anglo-Dutch war with a technical victory. Successive decisive Dutch victories in the second and third Anglo-Dutch Wars confirmed the Dutch mastery of the seas during the Dutch Golden Age , financed by the expansion of the Dutch Empire . The French Navy won some important victories near the end of the 17th century but a focus upon land forces led to
748-682: A military fleet, although the term " merchant navy " for a commercial fleet still incorporates the non-military word sense . This overlap in word senses between commercial and military fleets grew out of the inherently dual-use nature of fleets; centuries ago, nationality was a trait that unified a fleet across both civilian and military uses. Although nationality of commercial vessels has little importance in peacetime trade other than for tax avoidance , it can have greater meaning during wartime, when supply chains become matters of patriotic attack and defense, and when in some cases private vessels are even temporarily converted to military vessels. The latter
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#1732886752730816-801: A navy is projection of force into areas beyond a country's shores (for example, to protect sea-lanes , deter or confront piracy , ferry troops, or attack other navies, ports, or shore installations). The strategic defensive purpose of a navy is to frustrate seaborne projection-of-force by enemies. The strategic task of a navy also may incorporate nuclear deterrence by use of submarine-launched ballistic missiles . Naval operations can be broadly divided between riverine and littoral applications ( brown-water navy ), open-ocean applications ( blue-water navy ), and something in between ( green-water navy ), although these distinctions are more about strategic scope than tactical or operational division. First attested in English in
884-421: A number of frequencies, varying by country, between 120–148 kHz. Some radio frequency identification ( RFID ) tags utilize LF. These tags are commonly known as LFIDs or LowFIDs (low frequency identification). The LF RFID tags are near-field devices, interacting with the inductive near field , rather than with radiated waves (radio waves) that are the only part of the electromagnetic field that persists into
952-458: A single ship or aspect of a ship. However, commodores can also be temporary or honorary positions. For example, during World War II, a Navy captain was assigned duty as a convoy commodore, which meant that he was still a captain, but in charge of all the merchant vessels in the convoy. The most senior rank employed by a navy will tend to vary depending on the size of a navy and whether it is wartime or peacetime, for example, few people have ever held
1020-439: Is also possible to use cage antennas on grounded masts. For broadcasting stations, directional antennas are often required. They consist of multiple masts, which often have the same height. Some longwave antennas consist of multiple mast antennas arranged in a circle with or without a mast antenna in the center. Such antennas focus the transmitted power toward ground and give a large zone of fade-free reception. This type of antenna
1088-604: Is also referred to as the 1 750 meter band. Requirements include: Many experimenters in this band are amateur radio operators. A regular service transmitting RTTY marine meteorological information in SYNOP code on LF is the German Meteorological Service ( Deutscher Wetterdienst or DWD ). The DWD operates station DDH47 on 147.3 kHz using standard ITA-2 alphabet with a transmission speed of 50 baud and FSK modulation with 85 Hz shift. In parts of
1156-1206: Is an integral part of the navy but there are variations such as the French Troupes de marine , which is actually part of the French Army . The United States Marine Corps is a separate armed service within the United States Department of the Navy, with its own leadership structure. Naval aviation is the application of military air power by navies, whether from warships that embark aircraft, or land bases. In World War I, several navies used floatplanes and flying boats – mainly for scouting . By World War II, aircraft carriers could carry bomber aircraft capable of attacking naval and land targets, as well as fighter aircraft for defence. Since World War II helicopters have been embarked on smaller ships in roles such as anti-submarine warfare and transport. Some navies have also operated land-based aircraft in roles such as maritime patrol and training . Naval aviation forces primarily perform naval roles at sea. However, they are also used in
1224-472: Is currently building one aircraft carrier, INS Vikrant , and considering another. France is also looking at a new carrier , probably using a CATOBAR system and possibly based on the British Queen Elizabeth design. A navy typically operates from one or more naval bases . The base is a port that is specialized in naval operations, and often includes housing, a munitions depot , docks for
1292-979: Is rarely used, because they are very expensive and require much space and because fading occurs on longwave much more rarely than in the medium wave range. One antenna of this kind was used by transmitter Orlunda in Sweden. ELF 3 Hz/100 Mm 30 Hz/10 Mm SLF 30 Hz/10 Mm 300 Hz/1 Mm ULF 300 Hz/1 Mm 3 kHz/100 km VLF 3 kHz/100 km 30 kHz/10 km LF 30 kHz/10 km 300 kHz/1 km MF 300 kHz/1 km 3 MHz/100 m HF 3 MHz/100 m 30 MHz/10 m VHF 30 MHz/10 m 300 MHz/1 m UHF 300 MHz/1 m 3 GHz/100 mm SHF 3 GHz/100 mm 30 GHz/10 mm EHF 30 GHz/10 mm 300 GHz/1 mm THF 300 GHz/1 mm 3 THz/0.1 mm Navy A navy , naval force , military maritime fleet , war navy , or maritime force
1360-709: Is that boats are capable of being carried by ships. (Submarines by this rule are ships rather than boats, but are customarily referred to as boats reflecting their previous smaller size.) Navies use many types of boat, ranging from 9-foot (2.7 m) dinghies to 135-foot (41 m) landing craft. They are powered by either diesel engines, out-board gasoline engines, or waterjets. Most boats are built of aluminum, fiberglass, or steel. Rigid-hulled inflatable boats are also used. Patrol boats are used for patrols of coastal areas, lakes and large rivers. Landing craft are designed to carry troops, vehicles, or cargo from ship to shore under combat conditions, to unload, to withdraw from
1428-519: Is the ITU designation for radio frequencies (RF) in the range of 30–300 kHz . Since its wavelengths range from 10–1 km , respectively, it is also known as the kilometre band or kilometre wave s. LF radio waves exhibit low signal attenuation , making them suitable for long-distance communications. In Europe and areas of Northern Africa and Asia, part of the LF spectrum is used for AM broadcasting as
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#17328867527301496-429: Is the branch of a nation's armed forces principally designated for naval and amphibious warfare ; namely, lake -borne, riverine , littoral , or ocean -borne combat operations and related functions. It includes anything conducted by surface ships , amphibious ships, submarines , and seaborne aviation , as well as ancillary support, communications, training, and other fields. The strategic offensive role of
1564-532: Is vertical while the magnetic field is horizontal), so vertical monopole antennas are used for transmitting. The transmission distance is limited by the absorption of ground waves in the Earth. The attenuation of signal strength with distance is lower than at higher frequencies. Low frequency ground waves can be received up to 2,000 kilometres (1,200 mi) from the transmitting antenna. Low frequency waves can also occasionally travel long distances by reflecting from
1632-531: The 2 200 meter band (135.7–137.9 kHz) is available to amateur radio operators in several countries in Europe, New Zealand, Canada, US, and French overseas dependencies. The world record distance for a two-way contact is over 10,000 km from near Vladivostok to New Zealand . As well as conventional Morse code many operators use very slow computer-controlled Morse code (so-called "QRSS" ) or specialized digital communications modes. The UK allocated
1700-603: The BBC Radio 4 transmission on 198 kHz in waters near the UK. It is rumoured that they are to construe a sudden halt in transmission, particularly of the morning news programme Today , as an indicator that the UK is under attack, whereafter their sealed orders take effect. The United States has four LF stations maintaining contact with its submarine force: Aguada, Puerto Rico , Keflavik, Iceland , Awase, Okinawa , and Sigonella, Italy , using AN/FRT-95 solid state transmitters. In
1768-570: The Spanish and Portuguese navies that dominated in the 16th and early 17th centuries, and helped propel the age of exploration and colonialism . The repulsion of the Spanish Armada (1588) by the English fleet revolutionized naval warfare by the success of a guns-only strategy and caused a major overhaul of the Spanish Navy , partly along English lines, which resulted in even greater dominance by
1836-547: The ionosphere (the actual mechanism is one of refraction ), although this method, called skywave or "skip" propagation, is not as common as at higher frequencies. Reflection occurs at the ionospheric E layer or F layers . Skywave signals can be detected at distances exceeding 300 kilometres (190 mi) from the transmitting antenna. AM broadcasting is authorized in the longwave band on frequencies between 148.5 and 283.5 kHz in Europe and parts of Asia. In Europe and Japan, many low-cost consumer devices have since
1904-537: The oiler , minesweeper , patrol boat , hydrographic and oceanographic survey ship and tender . During the age of sail , the ship categories were divided into the ship of the line , frigate, and sloop-of-war . Naval ship names are typically prefixed by an abbreviation indicating the national navy in which they serve. For a list of the prefixes used with ship names ( HMS , USS , LÉ , etc.) see ship prefix . Today's warships are significantly faster than in years past, thanks to much improved propulsion systems. Also,
1972-496: The umbrella antenna and L- and T-antenna, use capacitive top-loading (a "top hat"), in the form of a network of horizontal wires attached to the top of the vertical radiator. The capacitance improves the efficiency of the antenna by increasing the current, without increasing its height. The height of antennas differ by usage. For some non-directional beacons (NDBs) the height can be as low as 10 meters, while for more powerful navigation transmitters such as DECCA , masts with
2040-434: The " longwave " band. In the western hemisphere, its main use is for aircraft beacons, navigation ( LORAN , mostly defunct), information, and weather systems. A number of time signal broadcasts also use this band. The main mode of transmission used in this band is ground waves , in which LF radio waves travel just above the Earth's surface, following the terrain. LF ground waves can travel over hills, and can travel far beyond
2108-679: The French Navy's relative neglect, which allowed the Royal Navy to emerge with an ever-growing advantage in size and quality, especially in tactics and experience, from 1695. As a response to growing naval influence of the navies of Portuguese, the warrior king of the Marathas, Shivaji laid the foundation of the Maratha navy in 1654. Throughout the 18th century the Royal Navy gradually gained ascendancy over
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2176-601: The French Navy, with victories in the War of Spanish Succession (1701–1714), inconclusive battles in the War of Austrian Succession (1740–1748), victories in the Seven Years' War (1754–1763), a partial reversal during the American War of Independence (1775–1783), and consolidation into uncontested supremacy during the 19th century from the Battle of Trafalgar in 1805. These conflicts saw
2244-745: The Spanish. From the beginning of the 17th century the Dutch cannibalized the Portuguese Empire in the East and, with the immense wealth gained, challenged Spanish hegemony at sea. From the 1620s, Dutch raiders seriously troubled Spanish shipping and, after a number of battles that went both ways, the Dutch Navy finally broke the long dominance of the Spanish Navy in the Battle of the Downs (1639). England emerged as
2312-533: The U.S. Navy lifted the ban in April 2010. The major reasons historically cited by the U.S. Navy were the extended duty tours and close conditions which afford almost no privacy. The United Kingdom's Royal Navy has had similar restrictions. Australia, Canada, Norway, and Spain previously opened submarine service to women sailors. A navy will typically have two sets of ranks, one for enlisted personnel and one for officers . Typical ranks for commissioned officers include
2380-525: The U.S., the Ground Wave Emergency Network or GWEN operated between 150 and 175 kHz, until replaced by satellite communications systems in 1999. GWEN was a land based military radio communications system which could survive and continue to operate even in the case of a nuclear attack. The 2007 World Radiocommunication Conference (WRC-07) made a worldwide amateur radio allocation in this band. An international 2.1 kHz allocation,
2448-713: The UK was received 3,275 miles (5,271 km) away, across the Atlantic Ocean , by W1TAG in the US on 21-22 November 2001 on 72.401 kHz. In the United States, there is an exemption within FCC Part ;15 regulations permitting unlicensed transmissions in the frequency range of 160–190 kHz. Longwave radio hobbyists refer to this as the ' LowFER ' band, and experimenters, and their transmitters are called ' LowFERs '. This frequency range between 160 kHz and 190 kHz
2516-560: The United Kingdom launched HMS Dreadnought in 1906, but naval tactics still emphasized the line of battle. The first practical military submarines were developed in the late 19th century and by the end of World War I had proven to be a powerful arm of naval warfare. During World War II , Nazi Germany 's submarine fleet of U-boats almost starved the United Kingdom into submission and inflicted tremendous losses on U.S. coastal shipping . The German battleship Tirpitz ,
2584-998: The beach, and to return to the ship. They are rugged, with powerful engines, and usually armed. There are many types in today's navies including hovercraft . They will typically have a power-operated bow ramp, a cargo well and after structures that house engine rooms, pilot houses, and stowage compartments. These boats are sometimes carried by larger ships. Special operations craft are high-speed craft used for insertion and extraction of special forces personnel and some may be transportable (and deployed) by air. Boats used in non-combat roles include lifeboats, mail boats, line handling boats, buoy boats, aircraft rescue boats, torpedo retrievers, explosive ordnance disposal craft, utility boats, dive boats, targets, and work boats. Boats are also used for survey work, tending divers, and minesweeping operations. Boats for carrying cargo and personnel are sometimes known as launches, gigs, barges or shore party boats. Naval forces are typically arranged into units based on
2652-450: The coastal periphery and along inland waterways, where larger ocean-going naval vessels can not readily enter. Regional powers may maintain a " green water navy " as a means of localized force projection. Blue water fleets may require specialized vessels, such as minesweepers , when operating in the littoral regions along the coast. A basic tradition is that all ships commissioned in a navy are referred to as ships rather than vessels, with
2720-539: The development and refinement of tactics that came to be called the line of battle . The next stage in the evolution of naval warfare was the introduction of metal plating along the hull sides. The increased mass required steam-powered engines, resulting in an arms race between armor and weapon thickness and firepower. The first armored vessels, the French Gloire and British HMS Warrior , made wooden vessels obsolete. Another significant improvement came with
2788-782: The early 14th century, the word "navy" came via Old French navie , "fleet of ships", from the Latin navigium , "a vessel, a ship, bark, boat", from navis , "ship". The word "naval" came from Latin navalis , "pertaining to ship"; cf. Greek ναῦς ( naus ), "ship", ναύτης ( nautes ), "seaman, sailor". The earliest attested form of the word is in the Mycenaean Greek compound word 𐀙𐀄𐀈𐀗 , na-u -do-mo (* naudomoi ), "shipbuilders", written in Linear B syllabic script. The word formerly denoted fleets of both commercial and military nature. In modern usage "navy" used alone always denotes
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2856-459: The efficiency of the engines has improved, in terms of fuel, and of how many sailors it takes to operate them. In World War II, ships needed to refuel very often. However, today ships can go on very long journeys without refueling. Also, in World War II, the engine room needed about a dozen sailors to work the many engines, however, today, only about four or five are needed (depending on the class of
2924-602: The enemy vessel so its occupants could be attacked hand-to-hand. Naval warfare continued in this vein through the Middle Ages until the cannon became commonplace and capable of being reloaded quickly enough to be reused in the same battle. In ancient China , large naval battles were known since the Qin dynasty ( also see Battle of Red Cliffs , 208), employing the war junk during the Han dynasty . However, China's first official standing navy
2992-496: The era of the Roman empire , naval forces included marine legionaries for maritime boarding actions . These were troops primarily trained in land warfare, and did not need to be skilled at handling a ship. Much later during the age of sail, a component of marines served a similar role, being ship-borne soldiers who were used either during boarding actions, as sharp-shooters, or in raids along shorelines. The Spanish Infantería de Marina
3060-484: The exact same frequency, and has a similar timecode . Radio signals below 50 kHz are capable of penetrating ocean depths to approximately 200 metres (660 ft); the longer the wavelength, the deeper they go. The British, German, Indian, Russian, Swedish, United States, and possibly other navies communicate with submarines on these frequencies. In addition, Royal Navy nuclear submarines carrying ballistic missiles are allegedly under standing orders to monitor
3128-417: The exception of destroyers and submarines, which are known as boats. The prefix on a ship's name indicates that it is a commissioned ship. An important tradition on board naval vessels of some nations has been the ship's bell . This was historically used to mark the passage of time, as warning devices in heavy fog, and for alarms and ceremonies. The ship's captain, and more senior officers are "piped" aboard
3196-565: The far field. As such, they are technically not radio devices nor radio antennas, even though they do operate at radio frequencies, and are called "antennas" in the RFID trade, but not in radio engineering . It is more proper, and technically more informative to think of them as secondary coils of very loosely coupled transformers . Since the ground waves used in this band require vertical polarization , vertical antennas are used for transmission. Mast radiators are most common, either insulated from
3264-451: The following, in ascending order ( Commonwealth ranks are listed first on each line; USA ranks are listed second in those instances where they differ from Commonwealth ranks): "Flag officers" include any rank that includes the word "admiral" (or commodore in services other than the US Navy), and are generally in command of a battle group , strike group or similar flotilla of ships, rather than
3332-727: The ground and fed at the bottom, or occasionally fed through guy-wires. T-antennas and inverted L-antennas are used when antenna height is an issue. LF transmitting antennas for high power transmitters require large amounts of space, and have been the cause of controversy in Europe and the United States, due to concerns about possible health hazards associated with human exposure to radio waves . Antenna requirements for LF reception are much more modest than for transmission. Although non-resonant long wire antennas are sometimes used, ferrite loop antennas are far more popular because of their small size. Amateur radio operators have achieved good LF reception using active antennas : A short whip with
3400-400: The horizon, up to several hundred kilometers from the transmitter. Because of their long wavelength , low frequency radio waves can diffract over obstacles like mountain ranges and travel beyond the horizon, following the contour of the Earth. This mode of propagation, called ground wave , is the main mode in the LF band. Ground waves must be vertically polarized (the electric field
3468-527: The invention of the rotating turrets, which allowed the guns to be aimed independently of ship movement. The battle between CSS Virginia and USS Monitor during the American Civil War (1861–1865) is often cited as the beginning of this age of maritime conflict. The Russian Navy was considered the third strongest in the world on the eve of the Russo-Japanese War , which turned to be
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#17328867527303536-444: The late 1980s contained radio clocks with an LF receiver for these signals. Since these frequencies propagate by ground wave only, the precision of time signals is not affected by varying propagation paths between the transmitter, the ionosphere, and the receiver. In the United States, such devices became feasible for the mass market only after the output power of WWVB was increased in 1997 and 1999. JJY transmitting broadcast on
3604-458: The number of ships included, a single ship being the smallest operational unit. Ships may be combined into squadrons or flotillas , which may be formed into fleets . The largest unit size may be the whole Navy or Admiralty . A task force can be assembled using ships from different fleets for an operational task. Despite their acceptance in many areas of naval service, female sailors were not permitted to serve on board U.S. submarines until
3672-416: The numerous United States carrier battle groups . Only two nations, the United States and France , presently operate CATOBAR carriers of any size, while Russia , China and India operate sizeable STOBAR carriers (although all three are originally of Russian design). The United Kingdom is also operating two Queen Elizabeth -class carriers, which are the largest STOVL vessels in service, and India
3740-432: The prow of the ship. Firing a cannon salute partially disarms the ship, so firing a cannon for no combat reason showed respect and trust. As the tradition evolved, the number of cannons fired became an indication of the rank of the official being saluted. Historically, navy ships were primarily intended for warfare. They were designed to withstand damage and to inflict the same, but only carried munitions and supplies for
3808-418: The radio transmitter, or the flashing light when radio silence was needed. A " blue water navy " is designed to operate far from the coastal waters of its home nation. These are ships capable of maintaining station for long periods of time in deep ocean, and will have a long logistical tail for their support. Many are also nuclear powered to save having to refuel. By contrast a " brown water navy " operates in
3876-627: The rank of Fleet Admiral in the U.S. Navy, the chief of the Royal Australian Navy holds the rank of Vice Admiral, and the chief of the Irish Naval Service holds the rank of Commodore. Naval infantry, commonly known as marines , are a category of infantry that form part of a state's naval forces and perform roles on land and at sea, including amphibious operations , as well as other, naval roles. They also perform other tasks, including land warfare, separate from naval operations. During
3944-715: The seafaring local people (either Malays of Srivijaya or Javanese of Mataram ) to attack as far as the coast of Tanzania and Mozambique with 1000 boats and attempted to take the citadel of Qanbaloh, about 7,000 km to their West, in 945–946 AD. In 1350 AD Majapahit launched its largest military expedition, the invasion of Pasai , with 400 large jong and innumerable smaller vessels. The second largest military expedition, invasion of Singapura in 1398, Majapahit deployed 300 jong with no less than 200,000 men. The average jong used by Majapahit would be about 76.18–79.81 m LOA , carrying 600–700 men, with 1200–1400 tons deadweight . The mass and deck space required to carry
4012-494: The ship using a Boatswain's call . In the United States, the First Navy Jack is a flag that has the words, "Don't Tread on Me" on the flag. By English tradition, ships have been referred to as a "she". However, it was long considered bad luck to permit women to sail on board naval vessels. To do so would invite a terrible storm that would wreck the ship. The only women that were welcomed on board were figureheads mounted on
4080-507: The ship). Today, naval strike groups on longer missions are always followed by a range of support and replenishment ships supplying them with anything from fuel and munitions, to medical treatment and postal services. This allows strike groups and combat ships to remain at sea for several months at a time. The term "boat" refers to small craft limited in their use by size and usually not capable of making lengthy independent voyages at sea. The old navy adage to differentiate between ships and boats
4148-400: The vessels, and various repair facilities. During times of war temporary bases may be constructed in closer proximity to strategic locations, as it is advantageous in terms of patrols and station-keeping. Nations with historically strong naval forces have found it advantageous to obtain basing rights in other countries in areas of strategic interest. Navy ships can operate independently or with
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#17328867527304216-695: The voyage (rather than merchant cargo). Often, other ships that were not built specifically for warfare, such as the galleon or the armed merchant ships in World War II , did carry armaments. In more recent times, navy ships have become more specialized and have included supply ships, troop transports, repair ships, oil tankers and other logistics support ships as well as combat ships. Modern navy combat ships are generally divided into seven main categories: aircraft carriers , cruisers , destroyers , frigates , corvettes , submarines , and amphibious assault ships . There are also support and auxiliary ships, including
4284-751: The world where there is no longwave broadcasting service, Non-directional beacons used for aeronavigation operate on 190–300 kHz (and beyond into the MW band). In Europe, Asia and Africa, the NDB allocation starts on 283.5 kHz. The LORAN -C radio navigation system operated on 100 kHz. In the past, the Decca Navigator System operated between 70 kHz and 129 kHz. The last Decca chains were closed down in 2000. Differential GPS telemetry transmitters operate between 283.5 and 325 kHz. The commercial " Datatrak " radio navigation system operates on
4352-625: The world's total numbers and total tonnage of naval vessels of 1,000 tons or greater. Throughout the rest of the 20th century, the United States Navy would maintain a tonnage greater than that of the next 17 largest navies combined. During the Cold War , the Soviet Navy became a significant armed force, with large numbers of large, heavily armed ballistic missile submarines and extensive use of heavy, long-ranged antisurface missiles to counter
4420-458: Was arguably the largest naval battle in history ; it was also the last battle in which battleships played a significant role. By the end of World War II , the carrier had become the dominant force of naval warfare. World War II also saw the United States become by far the largest naval power in the world. In the late 20th and early 21st centuries, the United States Navy possessed over 70% of
4488-482: Was especially important, and common, before 20th-century military technology existed, when merely adding artillery and naval infantry to any sailing vessel could render it fully as martial as any military-owned vessel. Such privateering has been rendered obsolete in blue-water strategy since modern missile and aircraft systems grew to leapfrog over artillery and infantry in many respects; but privateering nevertheless remains potentially relevant in littoral warfare of
4556-411: Was formed in 1537, making it the oldest, current marine force in the world. The British Royal Marines combine being both a ship-based force and also being specially trained in commando frogman -style operations and tactics, operating in some cases separately from the rest of the Royal Navy. The Royal Marines also have their own special forces unit . In the majority of countries, the marine force
4624-595: Was not established until the Southern Song dynasty in the 12th century, a time when gunpowder was a revolutionary new application to warfare. The Chola Dynasty in Southern India had a navy composed of trade ships transporting armies overseas. The Chola Navy reached its peak under Rajendra I , and was most notably used in invasions of Sri Lanka and Southeast Asia . Nusantaran thalassocracies made extensive use of naval power and technologies. This enabled
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