HOME
*



picture info

Stealth Ship
A stealth ship is a ship that employs stealth technology construction techniques in an effort to make it harder to detect by one or more of radar, visual, sonar, and infrared methods. These techniques borrow from stealth aircraft technology, although some aspects such as wake and acoustic signature reduction (acoustic quieting) are unique to stealth ships' design. Although radar cross-section (RCS) reduction is a fairly new concept, many other forms of masking a ship have existed for centuries or even millennia. Shaping In designing a ship with a reduced radar signature, the main concerns are radar beams originating near or slightly above the horizon (as seen from the ship) coming from distant patrol aircraft, other ships, or sea-skimming anti-ship missiles with active radar seekers. Therefore, the shape of the ship avoids vertical surfaces, which are effective at reflecting such beams directly back to the emitter. Retro-reflective right angles are eliminated to avoid the ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

USS Zumwalt (DDG-1000) At Night
USS ''Zumwalt'' (DDG-1000) is a guided missile destroyer of the United States Navy. She is the lead ship of the and the first ship to be named after Admiral Elmo Zumwalt. ''Zumwalt'' has stealth capabilities, having a radar cross-section similar to a fishing boat despite her large size. On 7 December 2015, ''Zumwalt'' began her sea trial preparatory to joining the Pacific Fleet. The ship was commissioned in Baltimore on 15 October 2016. Her home port is San Diego, California. Namesake ''Zumwalt'' is named after Elmo Russell Zumwalt Jr., who was an American naval officer and the youngest man to serve as the Chief of Naval Operations. As an admiral and later the 19th Chief of Naval Operations, Zumwalt played a major role in U.S. military history, especially during the Vietnam War. A highly decorated war veteran, Zumwalt reformed the US Navy's personnel policies in an effort to improve enlisted life and ease racial tensions. After he retired from a 32-year naval career, he la ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Stealth Aircraft
Stealth aircraft are designed to avoid detection using a variety of technologies that reduce reflection/emission of radar, infrared, visible light, radio frequency (RF) spectrum, and audio, collectively known as stealth technology. The F-117 Nighthawk was the first operational aircraft specifically designed around stealth technology. Other examples of stealth aircraft include the B-2 Spirit, the B-21 Raider, the F-22 Raptor, the F-35 Lightning II, the Chengdu J-20, and the Sukhoi Su-57. While no aircraft is totally invisible to radar, stealth aircraft make it more difficult for conventional radar to detect or track the aircraft effectively, increasing the odds of an aircraft successfully avoiding detection by enemy radar and/or avoiding being successfully targeted by radar guided weapons. Stealth is the combination of passive low observable (LO) features and active emitters such as low-probability-of-intercept radars, radios and laser designators. These are usually combined ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Type 45 Destroyer
The Type 45 destroyer, also known as the D or ''Daring'' class, is a Ship class, class of six guided-missile destroyers built for the United Kingdom's Royal Navy in the early 21st century. The class is primarily designed for Anti-aircraft warfare, anti-aircraft and anti-missile warfare and is built around the PAAMS (Sea Viper) air-defence system using the SAMPSON Active electronically scanned array (AESA) and the S1850M long-range radars. The first three destroyers were assembled by BAE Systems Surface Fleet Solutions from partially prefabricated "blocks" built at different shipyards; the remaining three were built by BAE Systems Maritime – Naval Ships. The first ship in the ''Daring'' class, HMS Daring (D32), HMS ''Daring'', was launched on 1 February 2006 and commissioned on 23 July 2009. The Type 45 destroyers were built to replace the Type 42 destroyer, Type 42 (''Sheffield''-class) destroyers that had served during the Falklands War, with the last Type 42 being decommissi ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Royal Navy
The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against France. The modern Royal Navy traces its origins to the early 16th century; the oldest of the UK's armed services, it is consequently known as the Senior Service. From the middle decades of the 17th century, and through the 18th century, the Royal Navy vied with the Dutch Navy and later with the French Navy for maritime supremacy. From the mid 18th century, it was the world's most powerful navy until the Second World War. The Royal Navy played a key part in establishing and defending the British Empire, and four Imperial fortress colonies and a string of imperial bases and coaling stations secured the Royal Navy's ability to assert naval superiority globally. Owing to this historical prominence, it is common, even among non-Britons, to ref ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Right Angle
In geometry and trigonometry, a right angle is an angle of exactly 90 Degree (angle), degrees or radians corresponding to a quarter turn (geometry), turn. If a Line (mathematics)#Ray, ray is placed so that its endpoint is on a line and the adjacent angles are equal, then they are right angles. The term is a calque of Latin ''angulus rectus''; here ''rectus'' means "upright", referring to the vertical perpendicular to a horizontal base line. Closely related and important geometrical concepts are perpendicular lines, meaning lines that form right angles at their point of intersection, and orthogonality, which is the property of forming right angles, usually applied to Euclidean vector, vectors. The presence of a right angle in a triangle is the defining factor for right triangles, making the right angle basic to trigonometry. Etymology The meaning of ''right'' in ''right angle'' possibly refers to the Classical Latin, Latin adjective ''rectus'' 'erect, straight, upright, perp ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Ship Camouflage
Ship camouflage is a form of military deception in which a ship is painted in one or more colors in order to obscure or confuse an enemy's visual observation. Several types of marine camouflage have been used or prototyped: blending or crypsis, in which a paint scheme attempts to hide a ship from view; deception, in which a ship is made to look smaller or, as with the Q-ships, to mimic merchantmen; and dazzle, a chaotic paint scheme which tries to confuse any estimate of distance, direction, or heading. Counterillumination, to hide a darkened ship against the slightly brighter night sky, was trialled by the Royal Canadian Navy in diffused lighting camouflage. Ships were sometimes camouflaged in classical times. Mediterranean pirate ships were sometimes painted blue-gray for concealment. Vegetius records that Julius Caesar's scout ships were painted bluish-green when gathering intelligence along the coast of Britain during the Gallic Wars. Ships were sometimes painted deceptively ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Visby-class Corvette
The ''Visby'' class is a warship in use by the Swedish Navy. It is the latest class of corvette adopted by the navy after the and corvettes. Its design emphasizes low visibility radar cross-section and Infrared homing, infrared signature, and the class has received widespread international attention because of its capabilities as a stealth ship. The first ship in the class is named after Visby, the main city on the island of Gotland. The ''Visby'' ships are designed by Swedish Defence Materiel Administration (FMV) and built by Kockums AB, Saab Kockums AB in Karlskrona. The first ship of the class was launched in 2000, but production then suffered repeated delays. The fifth and last ship was delivered in 2015. In 2021, an order was placed for the development of a second generation of evolved ''Visby'' corvettes. Design The hull is constructed with a sandwich design consisting of a PVC core with a carbon fibre and Polyvinyl chloride, vinyl laminate (see also the Oceanic-Cr ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Swedish Navy
The Swedish Navy ( sv, Svenska marinen) is the naval branch of the Swedish Armed Forces. It is composed of surface and submarine naval units – the Fleet () – as well as marine units, the Amphibious Corps (). In Swedish, vessels of the Swedish Navy are given the prefix "HMS", short for (His/Her Majesty's Ship). In English, this is sometimes changed to "HSwMS" ("His Swedish Majesty's Ship") to differentiate Swedish vessels from those of the British Royal Navy. Founded under King Gustav I in 1522, the Swedish navy is one of the oldest continuously serving navies in the world, celebrating its 500th anniversary in 2022. History Early Swedish kings ( 9th–14th centuries) organised a Swedish Navy along the coastline through . This involved combined rowing and sailing ships (without artillery). This system became obsolete with the development of society and changes in military technology. No later than in the 14th century, the duty to serve in was replaced by a tax ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Infrared Signature
Infrared signature, as used by defense scientists and the military, is the appearance of objects to infrared sensors. An infrared signature depends on many factors, including the shape and size of the object, temperature, and emissivity, reflection of external sources (earthshine, sunshine, skyshine) from the object's surface, the background against which it is viewed and the waveband of the detecting sensor. As such there is no all-encompassing definition of infrared signature nor any trivial means of measuring it. For example, the infrared signature of a truck viewed against a field will vary significantly with changing weather, time of day and engine loading. Two fairly successful examples of defining the infrared signature of an object are the apparent temperature difference at the sensor and the contrast radiant intensity (CRI) definitions. Apparent temperature difference The apparent temperature difference method of defining infrared signature gives the physical temperature ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Mack (naval Architecture)
In naval architecture, a mack is a structure which combines the Mast (ship)#Modern masts, radar masts and the funnel (ship), exhaust stack of a surface ship, thereby saving the upper deck space used for separate funnels and the increasingly large tripod masts used to carry heavy radar aerials. The word is a composite (portmanteau) of "mast" and "stack". It is a common design feature on post-WWII warships, (e.g. the rebuilt Baltimore class cruisers), and on some cruise ships. The Marine Nationale used a combined exhaust stack and rear director mast on Richelieu class battleships in the late 1930s. The Royal Navy used this design feature on the 1944 Weapon class destroyers, and the subsequent Daring class destroyer (1949), ''Daring''s, and in the diesel-engined Leopard class frigate, Type 41 "Cat" class and Salisbury class frigate, Type 61 "Cathedral" class frigates of the 1950s. It provided unbalanced and unattractive designs, which led to a reversion to separate masts and funnel ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Naval Sea Systems Command
The Naval Sea Systems Command (NAVSEA) is the largest of the United States Navy's five "systems commands," or materiel (not to be confused with "material") organizations. From a physical perspective, NAVSEA has four shipyards for shipbuilding, conversion, and repair, ten "warfare centers" (two undersea and eight surface), the NAVSEA headquarters, located at the Washington Navy Yard, in Washington D.C., and other locations in 15 states and 3 overseas continents. NAVSEA's primary objective is to engineer, build, buy, and maintain the U.S. Navy's fleet of ships and its combat systems. NAVSEA's budget of almost $30 billion accounts for nearly one quarter of the Navy's entire budget, with more than 80,200 personnel and 150 acquisition programs under its oversight. History The origin of NAVSEA dates to 1794, when Commodore John Barry was charged to oversee the construction of a 44-gun frigate and ensure that all business "harmonized and conformed" to the public's interest. Since the ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Arleigh Burke-class Destroyer
The ''Arleigh Burke'' class of guided-missile destroyers (DDGs) is a United States Navy class of destroyer built around the Aegis Combat System and the SPY-1D multi-function passive electronically scanned array radar. The class is named for Admiral Arleigh Burke, an American destroyer officer in World War II and later Chief of Naval Operations. The lead ship, , was commissioned during Admiral Burke's lifetime. These warships were designed as multi-mission destroyers, able to fulfill the strategic land strike role with Tomahawk missiles; anti-aircraft warfare (AAW) role with powerful Aegis radar and surface-to-air missiles; anti-submarine warfare (ASW) with towed array sonar, anti-submarine rockets, and ASW helicopters; and anti-surface warfare (ASuW) with Harpoon missiles. With upgrades to their AN/SPY-1 phased radar systems and their associated missile payloads as part of the Aegis Ballistic Missile Defense System, the ships of this class have also demonstrated capability ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]