Hampton, Virginia
Hampton is an independent city in the Commonwealth of Virginia in the United States. As of the 2010 census, the population was 137,436; as one of the seven major cities that compose the Hampton Roads metropolitan area, it is on the southeastern side of the Virginia Peninsula. Hampton traces its history to the city's Old Point Comfort, the home of Fort Monroe for 400 years, named by the 1607 voyagers, led by Captain Christopher Newport, who first established Jamestown as an English colonial settlement. Since consolidation in 1952, Hampton has included the former Elizabeth City County and the incorporated town of Phoebus, consolidated by a mutual agreement. After the end of the American Civil War, historic Hampton University was established opposite from the town on the Hampton River, providing an education for many newly-freed former slaves and for area Native Americans. In the 20th century, the area became the location of Langley Air Force Base, NASA Langley Research Center, the Virginia Air and Space Center.
Hampton features many miles of waterfront and beaches. For residents and visitors alike, the city features a wide array of business and industrial enterprises and residential areas, historical sites. Most the new Peninsula Town Center development opened in May 2010 on the site of the former Coliseum Mall. Located in the area adjacent to the Hampton Coliseum and the Convention Center, the new urbanism-type project features a wide mix of retail stores and other attractions. Development of new residential development and additional public facilities are underway at Buckroe Beach, long a noted resort area. Located on the Hampton Roads Beltway, it hosts the Hampton Roads Bridge-Tunnel on Interstate 64. First opened in 1957, it was the world's first bridge-tunnel, crossing the mouth of the Hampton Roads harbor, which serves as the gateway to the Chesapeake Bay and the Atlantic Ocean from the eastern United States' largest ice-free harbor and its tributary rivers. Expanded in the 1970s, the HRBT remains deepest such facility.
In December 1606, three ships carrying men and boys left England on a mission sponsored by a proprietary company. Lead by Captain Christopher Newport, they sailed across the Atlantic Ocean to North America. After a long voyage, they first landed at the entrance to the Chesapeake Bay on the south shore at a place they named Cape Henry. During the first few days of exploration, they identified the site of Old Point Comfort as a strategic defensive location at the entrance to the body of water that became known as Hampton Roads; this is formed by the confluence of the Elizabeth and James rivers. The latter is the longest river in Virginia. Weeks on May 14, 1607, they established the first permanent English settlement in the present-day United States about 25 miles further inland from the Bay which became the site of fortifications during the following 200 years. South, near the entrance to Hampton River, the colonists seized the Native American community of Kecoughtan under Virginia's Governor, Sir Thomas Gates.
The colonists established their own small town, with a small Anglican church, on July 9, 1610. This came to be known as part of Hampton.. Hampton was named for Henry Wriothesley, 3rd Earl of Southampton, an important leader of the Virginia Company of London, for whom the Hampton River, Hampton Roads and Southampton County were named; the area became part of Elizabeth Cittie in 1619, Elizabeth River Shire in 1634, was included in Elizabeth City County when it was formed in 1643. By 1680, the settlement was known as Hampton, it was incorporated as a town in 1705 and became the seat of Elizabeth City County. In the latter part of August 1619, an English ship flying a Dutch flag, the White Lion, appeared off shore from Point Comfort, its cargo included 20 plus Africans captured from the slave ship Sao Joao Bautista. These were the first Africans to come ashore on English-occupied land in what would become the United States. John Rolfe, the widower of Pocahontas, wrote in a letter that he was at Point Comfort and witnessed the arrival of the first Africans.
Although these first Bantu men from Angola were considered indentured servants, their arrival marked the beginning of slavery in North America. Two of the first Africans to arrive at Old Point Comfort in 1619 were Isabella, their child, the first of African descent born in North America, was born baptized January 1624. Shortly after the War of 1812, the US Army built a more substantial stone facility at Old Point Comfort, it was called Fort Monroe in honor of President James Monroe. The new installation and adjacent Fort Calhoun were completed in 1834. Fort Monroe and the surrounding area played several important roles during the American Civil War. Although most of Virginia became part of the Confederate States of America, Fort Monroe remained in Union hands, it became notable as a historic and symbolic site of early freedom for former slaves under the provisions of contraband policies and the Emancipation Proclamation. After the War, former Confederate President, Jefferson Davis was imprisoned in the area now known as the Casemate Museum on the base.
To the south of Fort Monroe, the Town of Hampton had the misfortune to be burned during both the American Revolutionary War and the American Civil War. From the ruins of Hampton left by evacuating Confederate
Armstrong Flight Research Center
The NASA Neil A. Armstrong Flight Research Center is an aeronautical research center operated by NASA, its primary campus is located inside Edwards Air Force Base in California and is considered NASA's premier site for aeronautical research. AFRC operates some of the most advanced aircraft in the world and is known for many aviation firsts, including critical support for the first manned airplane to exceed the speed of sound in level flight with the Bell X-1, highest speed recorded by a manned, powered aircraft, the first pure digital fly-by-wire aircraft, many others. AFRC operates a second site in Palmdale, Ca. known as Building 703, once the former Rockwell International/North American Aircraft production facility, at Air Force Plant 42. There, AFRC houses and operates several of NASA's Science Mission Directorate aircraft including SOFIA, a DC-8 Flying Laboratory, a Gulfstream C-20A UAVSAR and ER-2 High Altitude Platform. David McBride is the center's director. On March 1, 2014, the facility was renamed in honor of Neil Armstrong, a former test pilot at the center and the first human being to walk on the surface of the moon.
The center was known as the Dryden Flight Research Center from March 26, 1976, in honor of Hugh L. Dryden, a prominent aeronautical engineer who at the time of his death in 1965 was NASA's deputy administrator, it has previously been known as the National Advisory Committee for Aeronautics Muroc Flight Test Unit, the NACA High-Speed Flight Research Station, the NACA High-Speed Flight Station, the NASA High-Speed Flight Station and the NASA Flight Research Center. AFRC was the home of the Shuttle Carrier Aircraft, a modified Boeing 747 designed to carry a Space Shuttle orbiter back to Kennedy Space Center if one landed at Edwards; until 2004, Armstrong Flight Research Center operated the oldest B-52 Stratofortress bomber, a B-52B model, converted to drop test aircraft, dubbed'Balls 8.' It dropped a large number of supersonic test vehicles, ranging from the X-15 to its last research program, the hypersonic X-43A, powered by a Pegasus rocket. The aircraft was retired and is on display near the North Gate of Edwards.
Though Armstrong Flight Research Center has always been located on the shore of Rogers Dry Lake Bed, its precise location has changed over the years. It resides on the North Western Edge of the lakebed, just south of Edwards Air Force Bases' North Gate. Visitation to the center requires obtaining access to both Edwards AFB and NASA AFRC. Rogers dry lake bed offers a unique landscape, well suited for flight research. Dry conditions, few rainy days per year, large, open spaces in which emergency landings can be performed. At times, Rodgers dry lake bed can host a runway length of over 40,000 feet, is home to a 2000' diameter compass rose, in which aircraft can land into the wind in any direction. X-56 X-57 X-59 QueSST Dream Chaser UAS in the NAS TGALS NASA's predecessor, NACA, operated the Douglas Skyrocket. A successor to the Air Force's Bell X-1, the D-558-II could operate under jet power, it conducted extensive tests into aircraft stability in the transsonic range, optimal supersonic wing configurations, rocket plume effects, high-speed flight dynamics.
On November 20, 1953, the Douglas Skyrocket became the first aircraft to fly at over twice the speed of sound when it attained a speed of Mach 2.005. Like the X-1, the D-558-II could be air-launched using a B-29 Superfortress. Unlike the X-1, the Skyrocket could takeoff from a runway with the help of JATO units; the Controlled Impact Demonstration was a joint project with the Federal Aviation Administration to research a new jet fuel that would decrease the damage due to fire in the crash of a large airliner. On December 1, 1984, a remotely piloted Boeing 720 aircraft was flown into specially built wing openers which tore the wings open, fuel spraying everywhere. Despite the new fuel additive, the resulting fire ball was huge. Though the fuel additive did not prevent a fire, the research was not a complete failure; the additive still prevented the combustion of some fuel which flowed over the fuselage of the aircraft, served to cool it, similar to how a conventional rocket engine cools its nozzle.
Instrumented crash test dummies were in the airplane for the impact, provided valuable research into other aspects of crash survivability for the occupants. LASRE was a NASA experiment in cooperation with Lockheed Martin to study a reusable launch vehicle design based on a linear aerospike rocket engine; the experiment's goal was to provide in-flight data to help Lockheed Martin validate the computational predictive tools they developed to design the craft. LASRE was a half-span model of a lifting body with eight thrust cells of an aerospike engine; the experiment, mounted on the back of an SR-71 Blackbird aircraft, operated like a kind of "flying wind tunnel." The experiment focused on determining how a reusable launch vehicle's engine plume would affect the aerodynamics of its lifting body shape at specific altitudes and speeds reaching 750 miles per hour. The interaction of the aerodynamic flow with the engine plume could create drag; the Lunar Landing Research Vehicle or LLRV was an Apollo Project era program to build a simulator for the Moon landing.
The LLRVs, humorously referred to as "Flying Bedsteads", were used by the FRC, now known as the Armstrong Flight Research Center, at Edwards Air Force Base, Calif. to study and analyze piloting techniques needed to fly and land the Apo
Langley Research Center
Langley Research Center located in Hampton, United States, is the oldest of NASA's field centers. It directly borders the Back River on the Chesapeake Bay. LaRC has focused on aeronautical research, but has tested space hardware at the facility, such as the Apollo Lunar Module. In addition, a number of the earliest high-profile space missions were designed on-site. Established in 1917 by the National Advisory Committee for Aeronautics, the research center devotes two-thirds of its programs to aeronautics, the rest to space. LaRC researchers use more than 40 wind tunnels to study and improve aircraft and spacecraft safety and efficiency. Between 1958 and 1963, when NASA started Project Mercury, LaRC served as the main office of the Space Task Group. In June 2015, after serving as associate director deputy director, Dr. David E. Bowles was appointed director of NASA Langley. After US-German relations had deteriorated from neutral to hostile around 1916, the prospect of U. S. war entry became possible.
On February 15, 1917, the newly established Aviation Week warned that the U. S. military aviation capability was less than. President Woodrow Wilson sent Jerome Hunsaker to Europe to investigate, Hunsaker's report prompted Wilson to command the creation of the nation's first aeronautics laboratory, which became NASA Langley. In 1917, less than three years after it was created, the NACA established Langley Memorial Aeronautical Laboratory on Langley Field. Both Langley Field and the Langley Laboratory are named for aviation pioneer Samuel Pierpont Langley; the Aviation Section, U. S. Signal Corps had established a base there earlier that same year; the first research facilities were in place and aeronautical research was started by 1920. The laboratory included four researchers and 11 technicians. Langley Field and NACA began parallel growth as air power proved its utility during World War I; the center was established to explore the field of aerodynamic research involving airframe and propulsion engine design and performance.
In 1934 the world's largest wind tunnel was constructed at Langley Field with a 30 × 60 foot test section. It remained the world's largest wind tunnel until the 1940s, when a 40 × 80 foot tunnel was built at NASA Ames Research Center in California. Early in 1945, the center expanded to include rocket research, leading to the establishment of a flight station at Wallops Island, Virginia. A further expansion of the research program permitted Langley Research Center to orbit payloads, starting with NASA's Explorer 9 balloon satellite in mid-February 1961; as rocket research grew, aeronautics research continued to expand and played an important part when subsonic flight was advanced and supersonic and hypersonic flight were introduced. Langley Research Center can claim many historic firsts, some of which have proven to be revolutionary scientific breakthroughs; these accomplishments include the development of the concept of research aircraft leading to supersonic flight, the world's first transonic wind tunnels, the Lunar Landing Facility providing the simulation of lunar gravity, the Viking program for Mars exploration.
The center developed standards for the grooving of aircraft runways based on a previous British design used at Washington National Airport. Grooved runways reduce aquaplaning; this grooving is now the international standard for all runways around the world. Langley Research Center performs critical research on aeronautics, including wake vortex behavior, fixed-wing aircraft, rotary wing aircraft, aviation safety, human factors and aerospace engineering. LaRC supported the design and testing of the hypersonic X-43, which achieved a world speed record of Mach 9.6. LaRC assisted the NTSB in the investigation of the crash of American Airlines Flight 587. Work began in July 2011 to remove the 1940s era 16 feet transonic wind tunnel; the facility supported development and propulsion integration research for many military aircraft including all fighters since 1960 but had been inactive since 2004. Langley retained transonic wind tunnel testing capabilities facilities in the National Transonic Facility, a high pressure, cryogenically cooled 8.2 feet closed loop wind tunnel.
The EBF³ process produces structural metallic parts with immense strength, useful in performing repairs in remote locations. Additionally, the ability to build functionally graded, unitized parts directly from CAD data offers enhanced performance in numerous applications. LaRC has become home to this new type of machining process, used by their new room-sized electron-emitting device, which uses a High Frequency 42 kW, X-ray emitting electron gun, which melts either aluminum or titanium wire into the desired 3-dimensional metallic parts with a material strength comparable to that of wrought products; the machine's deposition rate is 150 in³/h, equivalent to its plastic-fabricating counterpart. Metallic parts are built directly from CAD without molds or tools, leaving the end product with no porosity. Other properties include: 6-axis positioning Heated or cooled platen 1×10−6 torr vacuum capability 72 × 24 × 24 inch build envelope Power efficiency in excess of 90% Near 100% feedstock efficiency Can deposit reflective materials not processable with lasers Potential portable EBF³ system (Unde
Jet aircraft
A jet aircraft is an aircraft propelled by jet engines. Whereas the engines in propeller-powered aircraft achieve their maximum efficiency at much lower speeds and altitudes, jet engines and aircraft achieve maximum efficiency at speeds close to or well above the speed of sound. Jet aircraft cruise at faster than about Mach 0.8 at altitudes around 10,000–15,000 metres or more. Frank Whittle, an English inventor and RAF officer, developed the concept of the jet engine in 1928, Hans von Ohain in Germany developed the concept independently in the early 1930s, he wrote in February 1936 to Ernst Heinkel, who led the construction of the world's first turbojet aircraft and jet plane Heinkel He 178. However, it can be argued that the English engineer A. A. Griffith, who published a paper in July 1926 on compressors and turbines deserves credit. After the first instance of powered flight, a large number of jet powerplants were suggested. René Lorin, Harris proposed systems for creating a jet efflux. In 1910 the Romanian inventor Henri Coandă filed a patent on a jet propulsion system which used piston-engine exhaust gases to add heat to an otherwise pure air stream compressed by rotating fan blades in a duct.
It was installed in his Coandă-1910 but this craft never flew. Rocket-powered jet aircraft were pioneered in Germany; the first aircraft to fly under rocket power was the Lippisch Ente, in 1928. The Ente had been flown as a glider; the next year, in 1929, the Opel RAK.1 became the first purpose-built rocket plane to fly. The turbojet was invented in the 1930s, independently by Frank Whittle and Hans von Ohain; the first turbojet aircraft to fly was the Heinkel He 178 V1 first prototype of the German Air Force, the Luftwaffe, on August 27, 1939 in Rostock. The first flight of a jet-engined aircraft to come to public attention was the Italian Caproni Campini N.1 motorjet prototype that flew on August 27, 1940. It was the first jet aircraft recognised by the Fédération Aéronautique Internationale. Campini had proposed the motorjet in 1932; the British experimental Gloster E.28/39 first took to the air on May 15, 1941, powered by Sir Frank Whittle's turbojet. The United States produced the Bell XP-59A using two examples of a version of the Whittle engine built by General Electric, which flew on October 1, 1942.
The Meteor was the first production jet as it entered production a few months before the Me 262, which itself had been in development since before the start of the war as Projekt 1065. The first operational jet fighter was the Messerschmitt Me 262, manufactured by Germany during World War II, which entered service on 19 April 1944 with Erprobungskommando 262 at Lechfeld just south of Augsburg, it was the fastest conventional aircraft of World War II – although there were faster aircraft propelled by unconventional means, such as the rocket-powered Messerschmitt Me 163 Komet. The Messerschmitt Me 262 had first flown on April 18, 1941, with initial plans drawn up by Dr Waldemar Voigt's design team in April 1939, but mass production did not start until early 1944 with the first squadrons operational that year, too late for a decisive effect on the outcome of the war. Around this time, mid 1944, the United Kingdom's Gloster Meteor was being committed to defence of the UK against the V-1 flying bomb – itself a pulsejet-powered aircraft and direct ancestor of the cruise missile– and ground-attack operations over Europe in the last months of the war.
In 1944 Germany introduced into service the Arado Ar 234 jet reconnaissance and bomber, though chiefly used in the former role, with the Heinkel He 162 Spatz single-jet light fighter premiering as 1944 ended. USSR tested its own Bereznyak-Isayev BI-1 in 1942, but the project was scrapped by Joseph Stalin in 1945; the Imperial Japanese Navy developed jet aircraft in 1945, including the Nakajima J9Y Kikka, a modified, smaller version of the Me 262 that had folding wings. By the end of 1945, the US had introduced their first jet fighter, the Lockheed P-80 Shooting Star into service and the UK its second fighter design, the de Havilland Vampire; the US introduced the North American B-45 Tornado, their first jet bomber, into service in 1948. Although capable of carrying nuclear weapons it was used for reconnaissance over Korea. On November 8, 1950, during the Korean War, United States Air Force Lt. Russell J. Brown, flying in an F-80, intercepted two North Korean MiG-15s near the Yalu River and shot them down in the first jet-to-jet dogfight in history.
The UK put the English Electric Canberra into service in 1951 as a light bomber. It was designed to fly faster than any interceptor. BOAC operated the first commercial jet service, from London to Johannesburg, in 1952 with the de Havilland Comet jetliner; this innovative aircraft travelled far faster and higher than the propeller aircraft, was much quieter and had stylish blended wings containing hidden jet engines. However, due to a design defect, use of aluminium alloys, the aircraft suffered catastrophic metal fatigue which led to several crashes; the series of crashes gave time for the Boeing 707 to enter service in 1958 and this came to dominate the market for civilian airliners. The underslung engines were found to be advantageous in the event of a propellant leak, so the 707 looked rather different from the Comet: the 707 has a shape, the same as that of contemporary aircraft, with marked commonality still evident today for example with the 737 and A340. Turbofan aircraft began ente
Gliding
Gliding is a recreational activity and competitive air sport in which pilots fly unpowered aircraft known as gliders or sailplanes using occurring currents of rising air in the atmosphere to remain airborne. The word soaring is used for the sport. Gliding as a sport began in the 1920s; the objective was to increase the duration of flights but soon pilots attempted cross-country flights away from the place of launch. Improvements in aerodynamics and in the understanding of weather phenomena have allowed greater distances at higher average speeds. Long distances are now flown using any of the main sources of rising air: ridge lift and lee waves; when conditions are favourable, experienced pilots can now fly hundreds of kilometres before returning to their home airfields. Some competitive pilots fly in races around pre-defined courses; these gliding competitions test pilots' abilities to make best use of local weather conditions as well as their flying skills. Local and national competitions are organized in many countries, there are biennial World Gliding Championships.
Techniques to maximize a glider's speed around the day's task in a competition have been developed, including the optimum speed to fly, navigation using GPS and the carrying of water ballast. If the weather deteriorates pilots are sometimes unable to complete a cross-country flight, they may need to land elsewhere in a field, but motorglider pilots can avoid this by starting an engine. Powered-aircraft and winches are the two most common means of launching gliders; these and other launch methods require assistance and facilities such as airfields and winches. These are provided by gliding clubs who train new pilots and maintain high safety standards. Although in most countries the standards of safety of the pilots and the aircraft are the responsibility of governmental bodies, the clubs and sometimes national gliding associations have delegated authority; the development of heavier-than-air flight in the half century between Sir George Cayley's coachman in 1853 and the Wright brothers in 1903 involved gliders.
However, the sport of gliding only emerged after the First World War, as a result of the Treaty of Versailles, which imposed severe restrictions on the manufacture and use of single-seat powered aircraft in Germany's Weimar Republic. Thus, in the 1920s and 1930s, while aviators and aircraft makers in the rest of the world were working to improve the performance of powered aircraft, the Germans were designing and flying more efficient gliders and discovering ways of using the natural forces in the atmosphere to make them fly farther and faster. With the active support of the German government, there were 50,000 glider pilots by 1937; the first German gliding competition was held at the Wasserkuppe in 1920, organized by Oskar Ursinus. The best flight set a world distance record of 2 kilometres. Within ten years, it had become an international event in which the achieved durations and distances had increased greatly. In 1931, Gunther Grönhoff flew 272 kilometres on the front of a storm from Munich to Kadaň in Western Czechoslovakia, farther than had been thought possible.
In the 1930s, gliding spread to many other countries. In the 1936 Summer Olympics in Berlin gliding was a demonstration sport, it was scheduled to be a full Olympic sport in the 1940 Games. A glider, the Olympia, was developed in Germany for the event. By 1939 the major gliding records were held by Russians, including a distance record of 748 kilometres. During the war, the sport of gliding in Europe was suspended, though several German fighter aces in the conflict, including Erich Hartmann, began their flight training in gliders. Gliding did not return to the Olympics after the war for two reasons: a shortage of gliders, the failure to agree on a single model of competition glider; the re-introduction of air sports such as gliding to the Olympics has been proposed by the world governing body, the Fédération Aéronautique Internationale, but has been rejected on the grounds of lack of public interest. In many countries during the 1950s, a large number of trained pilots wanted to continue flying.
Many were aeronautical engineers who could design and maintain gliders. They started both manufacturers, many of which still exist; this stimulated the development of both gliding and gliders, for example the membership of the Soaring Society of America increased from 1,000 to 16,000 by 1980. The increased numbers of pilots, greater knowledge and improving technology helped set new records, for example the pre-war altitude record was doubled by 1950, the first 1,000-kilometre flight was achieved in 1964. New materials such as glass fiber and carbon fiber, advances in wing shapes and airfoils, electronic instruments, the Global Positioning System and improved weather forecasting have since allowed many pilots to make flights that were once extraordinary. Today over 550 pilots have made flights over 1,000 kilometres. Although there is no Olympic competition, there are the World Gliding Championships; the first event was held at the Samedan in 1948. Since World War II it has been held every two years.
There are now six classes open to both sexes, plus three classes for two junior classes. The latest worldwide statistics for 2011 indicate that Germany, the sport's birthplace, is still a center of the gliding world: it accounted for 27 percent of the world's glider pilots, the three major glider man
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean in the south and is bounded by Asia and Australia in the west and the Americas in the east. At 165,250,000 square kilometers in area, this largest division of the World Ocean—and, in turn, the hydrosphere—covers about 46% of Earth's water surface and about one-third of its total surface area, making it larger than all of Earth's land area combined; the centers of both the Water Hemisphere and the Western Hemisphere are in the Pacific Ocean. The equator subdivides it into the North Pacific Ocean and South Pacific Ocean, with two exceptions: the Galápagos and Gilbert Islands, while straddling the equator, are deemed wholly within the South Pacific, its mean depth is 4,000 meters. The Mariana Trench in the western North Pacific is the deepest point in the world, reaching a depth of 10,911 meters; the western Pacific has many peripheral seas. Though the peoples of Asia and Oceania have traveled the Pacific Ocean since prehistoric times, the eastern Pacific was first sighted by Europeans in the early 16th century when Spanish explorer Vasco Núñez de Balboa crossed the Isthmus of Panama in 1513 and discovered the great "southern sea" which he named Mar del Sur.
The ocean's current name was coined by Portuguese explorer Ferdinand Magellan during the Spanish circumnavigation of the world in 1521, as he encountered favorable winds on reaching the ocean. He called it Mar Pacífico, which in both Portuguese and Spanish means "peaceful sea". Important human migrations occurred in the Pacific in prehistoric times. About 3000 BC, the Austronesian peoples on the island of Taiwan mastered the art of long-distance canoe travel and spread themselves and their languages south to the Philippines and maritime Southeast Asia. Long-distance trade developed all along the coast from Mozambique to Japan. Trade, therefore knowledge, extended to the Indonesian islands but not Australia. By at least 878 when there was a significant Islamic settlement in Canton much of this trade was controlled by Arabs or Muslims. In 219 BC Xu Fu sailed out into the Pacific searching for the elixir of immortality. From 1404 to 1433 Zheng He led expeditions into the Indian Ocean; the first contact of European navigators with the western edge of the Pacific Ocean was made by the Portuguese expeditions of António de Abreu and Francisco Serrão, via the Lesser Sunda Islands, to the Maluku Islands, in 1512, with Jorge Álvares's expedition to southern China in 1513, both ordered by Afonso de Albuquerque from Malacca.
The east side of the ocean was discovered by Spanish explorer Vasco Núñez de Balboa in 1513 after his expedition crossed the Isthmus of Panama and reached a new ocean. He named it Mar del Sur because the ocean was to the south of the coast of the isthmus where he first observed the Pacific. In 1519, Portuguese explorer Ferdinand Magellan sailed the Pacific East to West on a Spanish expedition to the Spice Islands that would result in the first world circumnavigation. Magellan called the ocean Pacífico because, after sailing through the stormy seas off Cape Horn, the expedition found calm waters; the ocean was called the Sea of Magellan in his honor until the eighteenth century. Although Magellan himself died in the Philippines in 1521, Spanish Basque navigator Juan Sebastián Elcano led the remains of the expedition back to Spain across the Indian Ocean and round the Cape of Good Hope, completing the first world circumnavigation in a single expedition in 1522. Sailing around and east of the Moluccas, between 1525 and 1527, Portuguese expeditions discovered the Caroline Islands, the Aru Islands, Papua New Guinea.
In 1542–43 the Portuguese reached Japan. In 1564, five Spanish ships carrying 379 explorers crossed the ocean from Mexico led by Miguel López de Legazpi, sailed to the Philippines and Mariana Islands. For the remainder of the 16th century, Spanish influence was paramount, with ships sailing from Mexico and Peru across the Pacific Ocean to the Philippines via Guam, establishing the Spanish East Indies; the Manila galleons operated for two and a half centuries, linking Manila and Acapulco, in one of the longest trade routes in history. Spanish expeditions discovered Tuvalu, the Marquesas, the Cook Islands, the Solomon Islands, the Admiralty Islands in the South Pacific. In the quest for Terra Australis, Spanish explorations in the 17th century, such as the expedition led by the Portuguese navigator Pedro Fernandes de Queirós, discovered the Pitcairn and Vanuatu archipelagos, sailed the Torres Strait between Australia and New Guinea, named after navigator Luís Vaz de Torres. Dutch explorers, sailing around southern Africa engaged in discovery and trade.
In the 16th and 17th centuries Spain considered the Pacific Ocean a mare clausum—a sea closed to other naval powers. As the only known entrance from the Atlantic, the Strait of Magellan was at times patrolled by fleets sent to prevent entrance of non-Spanish ships. On the western side of the Pacific Ocean the Dutch threatened the Spanish Philippines; the 18th cen
Wing
A wing is a type of fin that produces lift, while moving through air or some other fluid. As such, wings have streamlined cross-sections that are subject to aerodynamic forces and act as an airfoils. A wing's aerodynamic efficiency is expressed as its lift-to-drag ratio; the lift a wing generates at a given speed and angle of attack can be one to two orders of magnitude greater than the total drag on the wing. A high lift-to-drag ratio requires a smaller thrust to propel the wings through the air at sufficient lift. Lifting structures include various foils, including hydrofoils. Hydrodynamics is the governing science, rather than aerodynamics. Applications of underwater foils occur in hydroplanes and submarines; the word "wing" from the Old Norse vængr for many centuries referred to the foremost limbs of birds. But in recent centuries the word's meaning has extended to include lift producing appendages of insects, pterosaurs, some sail boats and aircraft, or the inverted airfoil on a race car that generates a downward force to increase traction.
The design and analysis of the wings of aircraft is one of the principal applications of the science of aerodynamics, a branch of fluid mechanics. The properties of the airflow around any moving object can – in principle – be found by solving the Navier-Stokes equations of fluid dynamics. However, except for simple geometries these equations are notoriously difficult to solve. However, simpler explanations can be described. For a wing to produce "lift", it must be oriented at a suitable angle of attack relative to the flow of air past the wing; when this occurs the wing deflects the airflow downwards. Since the wing exerts a force on the air to change its direction, the air must exert a force on the wing, equal in size but opposite in direction; this force manifests itself as differing air pressures at different points on the surface of the wing. A region of lower-than-normal air pressure is generated over the top surface of the wing, with a higher pressure on the bottom of the wing; these air pressure differences can be either measured directly using instrumentation, or can be calculated from the airspeed distribution using basic physical principles—including Bernoulli's principle, which relates changes in air speed to changes in air pressure.
The lower air pressure on the top of the wing generates a smaller downward force on the top of the wing than the upward force generated by the higher air pressure on the bottom of the wing. Hence, a net upward force acts on the wing; this force is called the "lift" generated by the wing. The different velocities of the air passing by the wing, the air pressure differences, the change in direction of the airflow, the lift on the wing are intrinsically one phenomenon, it is, possible to calculate lift from any of the other three. For example, the lift can be calculated from the pressure differences, or from different velocities of the air above and below the wing, or from the total momentum change of the deflected air. Fluid dynamics offers other approaches to solving these problems—and all produce the same answers if done correctly. Given a particular wing and its velocity through the air, debates over which mathematical approach is the most convenient to use can be mistaken by novices as differences of opinion about the basic principles of flight.
An airfoil or aerofoil is the shape of blade, or sail. Wings with an asymmetrical cross section are the norm in subsonic flight. Wings with a symmetrical cross section can generate lift by using a positive angle of attack to deflect air downward. Symmetrical airfoils have higher stalling speeds than cambered airfoils of the same wing area but are used in aerobatic aircraft as they provide practical performance whether the aircraft is upright or inverted. Another example comes from sailboats, where the sail is a thin membrane with no path-length difference between one side and the other. For flight speeds near the speed of sound, airfoils with complex asymmetrical shapes are used to minimize the drastic increase in drag associated with airflow near the speed of sound; such airfoils, called supercritical airfoils, are flat on top and curved on the bottom. Aircraft wings may feature some of the following: A rounded leading edge cross-section A sharp trailing edge cross-section Leading-edge devices such as slats, slots, or extensions Trailing-edge devices such as flaps or flaperons Winglets to keep wingtip vortices from increasing drag and decreasing lift Dihedral, or a positive wing angle to the horizontal, increases spiral stability around the roll axis, whereas anhedral, or a negative wing angle to the horizontal, decreases spiral stability.
Aircraft wings may have various devices, such as flaps or slats that the pilot uses to modify the shape and surface area of the wing to change its operating characteristics in flight. Ailerons to roll the aircraft clockwise or counterclockwise about its long axis Spoilers on the upper surface to disrupt the lift and to provide additional traction to an aircraft that has just landed but is still moving. Vortex generators to help prevent flow separation in transonic flow Wing fences to keep flow attached to the wing by stopping boundary layer separation from spreading roll direction. Folding wings allow more aircraft storage in the confined space of the hangar deck of an aircraft carrier Variable-sweep wing or "swing wings" that allow outstretched wings during low-speed flight and swept back wings for high-speed flight (includin
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