The Wide Area Augmentation System ( WAAS ) is an air navigation aid developed by the Federal Aviation Administration to augment the Global Positioning System (GPS), with the goal of improving its accuracy, integrity, and availability. Essentially, WAAS is intended to enable aircraft to rely on GPS for all phases of flight, including precision approaches to any airport within its coverage area. It may be further enhanced with the Local Area Augmentation System (LAAS) also known by the preferred ICAO term Ground-Based Augmentation System (GBAS) in critical areas.
98-551: WAAS uses a network of ground-based reference stations, in North America and Hawaii , to measure small variations in the GPS satellites' signals in the western hemisphere . Measurements from the reference stations are routed to master stations, which queue the received Deviation Correction (DC) and send the correction messages to geostationary WAAS satellites in a timely manner (every 5 seconds or better). Those satellites broadcast
196-561: A writing system , built huge pyramids and temples , had a complex calendar , and developed the concept of zero around 400 CE. The first recorded European references to North America are in Norse sagas where it is referred to as Vinland . The earliest verifiable instance of pre-Columbian trans-oceanic contact by any European culture with the North America mainland has been dated to around 1000 CE. The site , situated at
294-484: A Portland to Seattle flight operated by a Bombardier Q400 with a WAAS FMS from Universal Avionics. The airline, in partnership with the FAA, will outfit seven Q400-aircraft with WAAS and share flight data to better determine the suitability of WAAS in scheduled air service applications. Wide-Area Augmentation System (WAAS) Timeline WAAS addresses all of the "navigation problem", providing highly accurate positioning that
392-452: A navigation system includes the ability to provide timely warnings when its signal is providing misleading data that could potentially create hazards. The WAAS specification requires the system detect errors in the GPS or WAAS network and notify users within 6.2 seconds. Certifying that WAAS is safe for instrument flight rules (IFR) (i.e. flying in the clouds) requires proving there is only an extremely small probability that an error exceeding
490-612: A number of points (organized in a grid pattern) across the WAAS service area (see User Segment , below, to understand how these corrections are used). Once these correction messages are generated, the WMSs send them to two pairs of Ground Uplink Stations (GUS), which then transmit to satellites in the Space segment for rebroadcast to the User segment. Each FAA Air Route Traffic Control Center in
588-664: A period of mountain building called the Laramide orogeny , between 80 and 55 mya. The formation of the Isthmus of Panama that connected the continent to South America arguably occurred approximately 12 to 15 mya, and the Great Lakes (as well as many other northern freshwater lakes and rivers) were carved by receding glaciers about 10,000 years ago. North America is the source of much of what humanity knows about geologic time periods. The geographic area that would later become
686-590: A powerful earthquake killed seven people in 2009. Volcanic eruptions are common in the region. In 1968, the Arenal Volcano , in Costa Rica, erupted and killed 87 people. Fertile soils from weathered volcanic lavas have made it possible to sustain dense populations in agriculturally productive highland areas. Central America has many mountain ranges ; the longest are the Sierra Madre de Chiapas ,
784-451: A precision approach system or when flying low for other reasons. The FAA considered systems that could allow the same correction signals to be broadcast over a much wider area, such as from a satellite, leading directly to WAAS. Since a GPS unit already consists of a satellite receiver, it made much more sense to send out the correction signals on the same frequencies used by GPS units, than to use an entirely separate system and thereby double
882-444: A single easy-to-use system, often small enough to be hand held. Deploying an aircraft navigation system based on GPS was largely a problem of developing new techniques and standards, as opposed to new equipment. The FAA started planning to shut down their existing long-distance systems ( VOR and NDBs ) in favor of GPS. This left the problem of approaches, however. GPS is simply not accurate enough to replace ILS systems. Typical accuracy
980-470: A total time of four days per year (99% availability). The WAAS specification mandates availability as 99.999% ( five nines ) throughout the service area, equivalent to a downtime of just over 5 minutes per year. WAAS is composed of three main segments: the ground segment , space segment , and user segment. The ground segment is composed of multiple Wide-area Reference Stations (WRS). These precisely surveyed ground stations monitor and collect information on
1078-399: A variety of methods from the ground, or by examining the GPS signals themselves. By broadcasting this information to GPS receivers every minute or so, this source of error can be significantly reduced. This led to the concept of Differential GPS , which used separate radio systems to broadcast the correction signal to receivers. Aircraft could then install a receiver which would be plugged into
SECTION 10
#17327651302291176-540: A variety of reactions, including curiosity, trading, cooperation, resignation, and resistance. The indigenous population declined substantially following European arrival, primarily due to the introduction of Eurasian diseases, such as smallpox , to which the indigenous peoples lacked immunity, and because of violent conflicts with Europeans. Indigenous culture changed significantly and their affiliation with political and cultural groups also changed. Several linguistic groups died out , and others changed quite quickly. On
1274-665: Is a very large continent that extends from north of the Arctic Circle to south of the Tropic of Cancer . Greenland, along with the Canadian Shield , is tundra with average temperatures ranging from 10 to 20 °C (50 to 68 °F), but central Greenland is composed of a very large ice sheet. This tundra radiates throughout Canada, but its border ends near the Rocky Mountains (but still contains Alaska) and at
1372-473: Is about 15 metres (49 ft), whereas even a "CAT I" approach, the least demanding, requires a vertical accuracy of 4 metres (13 ft). This inaccuracy in GPS is mostly due to large "billows" in the ionosphere , which slow the radio signal from the satellites by a random amount. Since GPS relies on timing the signals to measure distances, this slowing of the signal makes the satellite appear farther away. The billows move slowly, and can be characterized using
1470-524: Is an ancient craton which forms the geologic core of North America; it formed between 1.5 and 1.0 billion years ago during the Proterozoic eon. The Canadian Shield is the largest exposure of this craton. From the Late Paleozoic to Early Mesozoic eras, North America was joined with the other modern-day continents as part of the supercontinent Pangaea , with Eurasia to its east. One of
1568-964: Is bordered to the north by the Arctic Ocean , to the east by the Atlantic Ocean , to the southeast by South America and the Caribbean Sea , and to the west and south by the Pacific Ocean . The region includes the Bahamas , Bermuda , Canada , the Caribbean , Central America , Clipperton Island , Greenland , Mexico , Saint Pierre and Miquelon , Turks and Caicos Islands , and the United States . North America covers an area of about 24,709,000 square kilometers (9,540,000 square miles), representing approximately 16.5% of
1666-401: Is extremely easy to use, for the cost of a single receiver installed on the aircraft. Ground- and space-based infrastructure is relatively limited, and no on-airport system is needed. WAAS allows a precision approach to be published for any airport, for the cost of developing the procedures and publishing the new approach plates. This means that almost any airport can have a precision approach and
1764-546: Is in present-day Panama at the Darien Gap on the Colombia -Panama border, placing almost all of Panama within North America. Alternatively, some geologists physiographically locate its southern limit at the Isthmus of Tehuantepec , Mexico, with Central America extending southeastward to South America from this point. The Caribbean islands, or West Indies, are considered part of North America. The continental coastline
1862-648: Is long and irregular. The Gulf of Mexico is the largest body of water indenting the continent, followed by Hudson Bay . Others include the Gulf of Saint Lawrence and the Gulf of California . Before the Central American isthmus formed, the region had been underwater. The islands of the West Indies delineate a submerged former land bridge , which had connected North and South America via what are now Florida and Venezuela . There are several islands off
1960-561: Is part of North America geographically. In a geologic sense, Bermuda is not part of the Americas, but an oceanic island that was formed on the fissure of the Mid-Atlantic Ridge over 100 million years ago (mya). The nearest landmass to it is Cape Hatteras , North Carolina . However, Bermuda is often thought of as part of North America, especially given its historical, political and cultural ties to Virginia and other parts of
2058-707: Is the Morrison Formation of the western U.S. Canada is geologically one of the oldest regions in the world, with more than half of the region consisting of Precambrian rocks that have been above sea level since the beginning of the Palaeozoic era. Canada's mineral resources are diverse and extensive. Across the Canadian Shield and in the north there are large iron, nickel, zinc , copper, gold, lead, molybdenum , and uranium reserves. Large diamond concentrations have been recently developed in
SECTION 20
#17327651302292156-527: Is the humid subtropical climate . This area has the wettest cities in the contiguous U.S. , with annual precipitation reaching 67 in (1,700 mm) in Mobile, Alabama . Stretching from the borders of the humid continental and subtropical climates, and going west to the Sierra Nevada , south to the southern tip of Durango , north to the border with tundra climate, the steppe / desert climates are
2254-526: The 50 states has a WAAS reference station, except for Indianapolis . There are also stations positioned in Canada, Mexico and Puerto Rico. See List of WAAS reference stations for the coordinates of the individual receiving antennas. The space segment consists of multiple communication satellites which broadcast the correction messages generated by the WAAS Master Stations for reception by
2352-729: The Americas at least 20,000 years ago, but various evidence points to possibly earlier dates. The Paleo-Indian period in North America followed the Last Glacial Period, and lasted until about 10,000 years ago when the Archaic period began. The classic stage followed the Archaic period, and lasted from approximately the 6th to 13th centuries. Beginning in 1000 AD, the Norse were the first Europeans to begin exploring and ultimately colonizing areas of North America. In 1492,
2450-567: The Bering Strait during the Early-Middle Holocene . Prior to the arrival of European explorers and colonists in North America, the natives of North America were divided into many different polities, ranging from small bands of a few families to large empires. They lived in several culture areas , which roughly correspond to geographic and biological zones that defined the representative cultures and lifestyles of
2548-600: The British Columbia Coast , Western Canada , and Northern Canada . In the U.S., they include New England , the Mid-Atlantic , South Atlantic states , East North Central states , West North Central states , East South Central states , West South Central states , Mountain states , and Pacific states . The Great Lakes region and the Pacific Northwest include areas in both Canada and
2646-913: The Caribbean Plate , whereas the Juan de Fuca Plate and Cocos Plate border the North American Plate on its western frontier. The continent can be divided into four great regions (each of which contains many subregions): the Great Plains stretching from the Gulf of Mexico to the Canadian Arctic ; the geologically young, mountainous west, including the Rocky Mountains , the Great Basin , California , and Alaska ;
2744-568: The Cordillera Isabelia , and the Cordillera de Talamanca . Between the mountain ranges lie fertile valleys that are suitable for the people; in fact, most of the population of Honduras, Costa Rica, and Guatemala live in valleys. Valleys are also suitable for the production of coffee, beans, and other crops. The indigenous peoples of the Americas have many creation myths , based on which they assert that they have been present on
2842-502: The Earth 's land area and 4.8% of its total surface area. It is the third-largest continent by size after Asia and Africa , and the fourth-largest continent by population after Asia, Africa, and Europe . As of 2021 , North America's population was estimated as over 592 million people in 23 independent states , or about 7.5% of the world's population. In human geography , the terms "North America" and "North American" can refer to Canada,
2940-465: The East Coast to eastern North Dakota , and stretching down to Kansas , is the humid continental climate featuring intense seasons, with a large amount of annual precipitation, with places like New York City averaging 50 in (1,300 mm). Starting at the southern border of the humid continental climate and stretching to the Gulf of Mexico (whilst encompassing the eastern half of Texas)
3038-620: The Inuit of the high Arctic arrived in North America much later than other native groups, evidenced by the disappearance of Dorset culture artifacts from the archaeological record and their replacement by the Thule people . During the thousands of years of native habitation on the continent, cultures changed and shifted. One of the oldest yet discovered is the Clovis culture (c. 9550–9050 BCE) in modern New Mexico . Later groups include
Wide Area Augmentation System - Misplaced Pages Continue
3136-719: The Mississippian culture and related Mound building cultures, found in the Mississippi River valley and the Pueblo culture of what is now the Four Corners . The more southern cultural groups of North America were responsible for the domestication of many common crops now used around the world, such as tomatoes, squash , and maize . As a result of the development of agriculture in the south, many other cultural advances were made there. The Mayans developed
3234-488: The first official name given to Mexico. North America includes several regions and subregions, each of which have their own respective cultural, economic, and geographic regions. Economic regions include several regions formalized in 20th- and 21st-century trade agreements, including NAFTA between Canada , Mexico , and the United States , and CAFTA between Central America , the Dominican Republic , and
3332-415: The $ 1,000,000 to $ 1,500,000 cost to install an ILS radio system. For all its benefits, WAAS is not without drawbacks and critical limitations: In 2007, WAAS vertical guidance was projected to be available nearly all the time (greater than 99%), and its coverage encompasses the full continental U.S., most of Alaska, northern Mexico, and southern Canada. At that time, the accuracy of WAAS would meet or exceed
3430-458: The 1490s, building cities, putting the resident indigenous populations to work, raising crops for Spanish settlers and panning gold to enrich the Spaniards. Much of the indigenous population died due to disease and overwork, spurring the Spaniards on to claim new lands and peoples. An expedition under the command of Spanish settler, Hernán Cortés , sailed westward in 1519 to what turned out to be
3528-630: The Arctic, making Canada one of the world's largest producers. Throughout the Shield, there are many mining towns extracting these minerals. The largest, and best known, is Sudbury , Ontario. Sudbury is an exception to the normal process of forming minerals in the Shield since there is significant evidence that the Sudbury Basin is an ancient meteorite impact crater . The nearby, but less-known Temagami Magnetic Anomaly has striking similarities to
3626-555: The CONUS, the 100% availability LPV-200 coverage rises from 48% to 84%, with 100% coverage of the LPV solution. Both Galaxy XV (PRN #135) and Anik F1R (PRN #138) contain an L1 & L5 GPS payload. This means they will potentially be usable with the L5 modernized GPS signals when the new signals and receivers become available. With L5, avionics will be able to use a combination of signals to provide
3724-651: The Caribbean islands. France took the western half of Hispaniola and developed Saint-Domingue as a cane sugar producing colony worked by black slave labor. Britain took Barbados and Jamaica , and the Dutch and Danes took islands previously claimed by Spain. Britain did not begin settling on the North American mainland until a hundred years after the first Spanish settlements, since it sought first to control nearby Ireland . The first permanent English settlement
3822-635: The Cod fish", in reference to the abundance of cod fish on the East Coast . Waldseemüller used the Latin version of Vespucci's name, Americus Vespucius, in its feminine form of "America", following the examples of "Europa", "Asia", and "Africa". Americus originated from Medieval Latin Emericus (see Saint Emeric of Hungary ), coming from the Old High German name Emmerich . Map makers later extended
3920-421: The GPS signal to meet the requirements for a precision approach (see GPS sources of error ). A precision approach includes altitude information and provides course guidance, distance from the runway, and elevation information at all points along the approach, usually down to lower altitudes and weather minimums than non-precision approaches. Prior to the WAAS, the U.S. National Airspace System (NAS) did not have
4018-663: The GPS signals, then send their data to three Wide-area Master Stations (WMS) using a terrestrial communications network. The reference stations also monitor signals from WAAS geostationary satellites, providing integrity information regarding them as well. As of October 2007 there were 38 WRSs: twenty in the contiguous United States (CONUS), seven in Alaska, one in Hawaii, one in Puerto Rico, five in Mexico, and four in Canada. Using
Wide Area Augmentation System - Misplaced Pages Continue
4116-404: The GPS unit, the signal being broadcast on a variety of frequencies for different users (FM radio for cars, longwave for ships, etc.). Broadcasters of the required power generally cluster around larger cities, making such DGPS systems less useful for wide-area navigation. Additionally, most radio signals are either line-of-sight, or can be distorted by the ground, which made DGPS difficult to use as
4214-815: The Japanese Multi-functional Satellite Augmentation System (MSAS) and the Russian System for Differential Corrections and Monitoring (SDCM), respectively. Commercial systems include StarFire , OmniSTAR , and Atlas . A primary goal of WAAS was to allow aircraft to make a Category I approach without any equipment being installed at the airport. This would allow new GPS-based instrument landing approaches to be developed for any airport, even ones without any ground equipment. A Category I approach requires an accuracy of 16 metres (52 ft) laterally and 4.0 metres (13.1 ft) vertically. To meet this goal,
4312-419: The North America's southeastern coast, Spanish explorer Juan Ponce de León , who had accompanied Columbus's second voyage, visited and named in 1513 La Florida . As the colonial period unfolded, Spain, England, and France appropriated and claimed extensive territories in North America eastern and southern coastlines. Spain established permanent settlements on the Caribbean islands of Hispaniola and Cuba in
4410-479: The Sudbury Basin. Its magnetic anomalies are very similar to the Sudbury Basin, and so it could be a second metal-rich impact crater. The Shield is also covered by vast boreal forests that support an important logging industry. The United States can be divided into twelve main geological provinces: Each province has its own geologic history and unique features. The geology of Alaska is typical of that of
4508-535: The U.S. North America occupies the northern portion of the landmass generally referred to as the New World, the Western Hemisphere , the Americas, or simply America, which, in many countries, is considered a single continent with North America a subcontinent . North America is the third-largest continent by area after Asia and Africa . North America's only land connection to South America
4606-553: The United States has been the source of more varieties of dinosaurs than any other modern country. According to paleontologist Peter Dodson, this is primarily due to stratigraphy, climate and geography, human resources, and history. Much of the Mesozoic Era is represented by exposed outcrops in the many arid regions of the continent. The most significant Late Jurassic dinosaur-bearing fossil deposit in North America
4704-611: The United States, Mexico, and Greenland or, alternatively, Canada, Greenland and the US (Mexico being classified as part of Latin America ) or simply Canada and the US (Greenland being classified as either Arctic or European (due to its political status as a part of Denmark) and Mexico classified as Latin American). It is unknown with certainty how and when first human populations first reached North America. People were known to live in
4802-550: The United States, and Mexico. France , Italy , Portugal , Spain , Romania , Greece , and the countries of Latin America use a six-continent model , with the Americas viewed as a single continent and North America designating a subcontinent comprising Canada , the United States , Mexico, and Saint Pierre and Miquelon (politically part of France), and often including Greenland and Bermuda . North America has historically been known by other names, including Spanish North America, New Spain , and América Septentrional,
4900-579: The United States. North America is divided linguistically and culturally into two primary regions, Anglo-America and Latin America . Anglo-America includes most of North America, Belize , and Caribbean islands with English -speaking populations. There are also regions, including Louisiana and Quebec , with large Francophone populations; in Quebec , French is the official language. . The southern portion of North America includes Central America and non-English speaking Caribbean nations. The north of
4998-405: The WAAS signal, serving all 5,400 public use airports, is just under US$ 50 million per year. In comparison, the current ground based systems such as the Instrument Landing System (ILS), installed at only 600 airports, cost US$ 82 million in annual maintenance. Without ground navigation hardware to purchase, the total cost of publishing a runway's WAAS approach is approximately US$ 50,000; compared to
SECTION 50
#17327651302295096-483: The WAAS specification requires it to provide a position accuracy of 7.6 metres (25 ft) or less (for both lateral and vertical measurements), at least 95% of the time. Actual performance measurements of the system at specific locations have shown it typically provides better than 1.0 metre (3 ft 3 in) laterally and 1.5 metres (4 ft 11 in) vertically throughout most of the contiguous United States and large parts of Canada and Alaska . Integrity of
5194-408: The ability to provide lateral and vertical navigation for precision approaches for all users at all locations. The traditional system for precision approaches is the instrument landing system (ILS), which used a series of radio transmitters each broadcasting a single signal to the aircraft. This complex series of radios needs to be installed at every runway end, some offsite, along a line extended from
5292-435: The area had shifted to the Aztec Empire , whose capital city Tenochtitlan was located further north in the Valley of Mexico . The Aztecs were conquered in 1521 by Hernán Cortés . During the so-called Age of Discovery , Europeans explored overseas and staked claims to various parts of North America, much of which was already settled by indigenous peoples. Upon Europeans' arrival in the " New World ", indigenous peoples had
5390-432: The continent maintains recognized regions as well. In contrast to the common definition of North America, which encompasses the whole North American continent, the term "North America" is sometimes used more narrowly to refer only to four nations, Canada, Greenland, Mexico, and the U.S. The U.S. Census Bureau includes Saint Pierre and Miquelon, but excludes Mexico from its definition. The term Northern America refers to
5488-452: The continent's coasts; principally, the Arctic Archipelago, the Bahamas , Turks and Caicos , the Greater and Lesser Antilles , the Aleutian Islands (some of which are in the Eastern Hemisphere proper), the Alexander Archipelago , the many thousand islands of the British Columbia Coast, and Newfoundland. Greenland , a self-governing Danish island, and the world's largest , is on the same tectonic plate (the North American Plate ) and
5586-410: The continent. The vast majority of North America is on the North American Plate. Parts of western Mexico, including Baja California, and of California , including the cities of San Diego , Los Angeles , and Santa Cruz , lie on the eastern edge of the Pacific Plate , with the two plates meeting along the San Andreas Fault . The southernmost portion of the continent and much of the West Indies lie on
5684-604: The cordillera, while the major islands of Hawaii consist of Neogene volcanics erupted over a hot spot . Central America is geologically active with volcanic eruptions and earthquakes occurring from time to time. In 1976 Guatemala was hit by a major earthquake , killing 23,000 people; Managua, the capital of Nicaragua, was devastated by earthquakes in 1931 and 1972, the last one killing about 5,000 people; three earthquakes devastated El Salvador, one in 1986 and two in 2001; one earthquake devastated northern and central Costa Rica in 2009, killing at least 34 people; in Honduras
5782-445: The correction messages back to Earth, where WAAS-enabled GPS receivers use the corrections while computing their positions to improve accuracy. The International Civil Aviation Organization (ICAO) calls this type of system a satellite-based augmentation system (SBAS). Europe and Asia are developing their own SBASs: the Indian GPS Aided Geo Augmented Navigation (GAGAN), the European Geostationary Navigation Overlay Service (EGNOS),
5880-517: The cost of implementation is drastically reduced. Additionally WAAS works just as well between airports. This allows the aircraft to fly directly from one airport to another, as opposed to following routes based on ground-based signals. This can cut route distances considerably in some cases, saving both time and fuel. In addition, because of its ability to provide information on the accuracy of each GPS satellite's information, aircraft equipped with WAAS are permitted to fly at lower en-route altitudes than
5978-460: The cost of implementation. MLS also offered a number of practical advantages that eased traffic considerations, both for aircraft and radio channels. Unfortunately, MLS would also require every airport and aircraft to upgrade their equipment. During the development of MLS, consumer GPS receivers of various quality started appearing. GPS offered a huge number of advantages to the pilot, combining all of an aircraft's long-distance navigation systems into
SECTION 60
#17327651302296076-514: The cultures of the region commonly reflect Western traditions . However, relatively small parts of North America in Canada, the United States, Mexico, and Central America have indigenous populations that continue adhering to their respective pre-European colonial cultural and linguistic traditions. The Americas were named after the Italian explorer Amerigo Vespucci by German cartographers Martin Waldseemüller and Matthias Ringmann . Vespucci explored South America between 1497 and 1502, and
6174-558: The data from the WRS sites, the WMSs generate two different sets of corrections: fast and slow. The fast corrections are for errors which are changing rapidly and primarily concern the GPS satellites' instantaneous positions and clock errors. These corrections are considered user position-independent, which means they can be applied instantly by any receiver inside the WAAS broadcast footprint . The slow corrections include long-term ephemeric and clock error estimates, as well as ionospheric delay information. WAAS supplies delay corrections for
6272-447: The driest in the U.S. Highland climates cut from north to south of the continent, where subtropical or temperate climates occur just below the tropics, as in central Mexico and Guatemala . Tropical climates appear in the island regions and in the subcontinent's bottleneck, found in countries and states bathed by the Caribbean Sea or to the south of the Gulf of Mexico and the Pacific Ocean . Precipitation patterns vary across
6370-408: The end of the Canadian Shield, near the Great Lakes . Climate west of the Cascade Range is described as being temperate weather with average precipitation 20 inches (510 millimeters). Climate in coastal California is described to be Mediterranean , with average temperatures in cities like San Francisco ranging from 57 to 70 °F (14 to 21 °C) over the course of the year. Stretching from
6468-447: The end of the Inmarsat lease approaching, two new satellites ( Galaxy 15 and Anik F1R ) were launched in late 2005. Galaxy 15 is a PanAmSat and Anik F1R is a Telesat . As with the previous satellites, these are leased services under the FAA's Geostationary Satellite Communications Control Segment contract with Lockheed Martin for WAAS geostationary satellite leased services, who were contracted to provide up to three satellites through
6566-544: The exploratory voyages of Christopher Columbus led to a transatlantic exchange , including migrations of European settlers during the Age of Discovery and the early modern period . Present-day cultural and ethnic patterns reflect interactions between European colonists, indigenous peoples , enslaved Africans , immigrants from Europe, Asia, and descendants of these respective groups. Europe's colonization in North America led to most North Americans speaking European languages, such as English , Spanish , and French , and
6664-419: The fast type of correction data, which includes the corrected satellite position and clock data, and determines its current location using normal GPS calculations. Once an approximate position fix is obtained the receiver begins to use the slow corrections to improve its accuracy. Among the slow correction data is the ionospheric delay. As the GPS signal travels from the satellite to the receiver, it passes through
6762-421: The first American inhabitants sailed from Beringia some 13,000 years ago, with widespread habitation of the Americas during the end of the Last Glacial Period , in what is known as the Late Glacial Maximum , around 12,500 years ago. The oldest petroglyphs in North America date from 15,000 to 10,000 years before present. Genetic research and anthropology indicate additional waves of migration from Asia via
6860-410: The first designer of helicopter WAAS with Localizer Performance (LP) and Localizer Performance with Vertical guidance (LPV) approaches, and the only entity with FAA-approved criteria (which even FAA has yet to develop). This helicopter WAAS criteria offers as low as 250 foot minimums and decreased visibility requirements to enable missions previously not possible. On April 1, 2009, FAA AFS-400 approved
6958-462: The first three helicopter WAAS GPS approach procedures for Hickok & Associates' customer California Shock/Trauma Air Rescue (CALSTAR). Since then they have designed many approved WAAS helicopter approaches for various EMS hospitals and air providers, within the United States as well as in other countries and continents. On December 30, 2009, Seattle-based Horizon Air flew the first scheduled-passenger service flight using WAAS with LPV on flight 2014,
7056-847: The geographic center of either the 50 states, the conterminous United States, or the North American continent." Nonetheless, there is a 4.6-meter (15 ft) field stone obelisk in Rugby claiming to mark the center. The North American continental pole of inaccessibility is located 1,650 km (1,030 mi) from the nearest coastline, between Allen and Kyle, South Dakota at 43°22′N 101°58′W / 43.36°N 101.97°W / 43.36; -101.97 ( Pole of Inaccessibility North America ) . Canada can be divided into roughly seven physiographic divisions: The lower 48 U.S. states can be divided into roughly eight physiographic divisions: Mexico can be divided into roughly fifteen physiographic divisions: North America
7154-419: The indigenous people who lived there, including the bison hunters of the Great Plains and the farmers of Mesoamerica . Native groups also are classified by their language families , which included Athapascan and Uto-Aztecan languages. Indigenous peoples with similar languages did not always share the same material culture , however, and were not necessarily always allies. Anthropologists speculate that
7252-447: The ionosphere. The receiver calculates the location where the signal pierced the ionosphere and, if it has received an ionospheric delay value for that location, corrects for the error the ionosphere created. While the slow data can be updated every minute if necessary, ephemeris errors and ionosphere errors do not change this frequently, so they are only updated every two minutes and are considered valid for up to six minutes. The WAAS
7350-468: The land since its creation, but there is no evidence that humans evolved there. The specifics of the initial settlement of the Americas by ancient Asians are subject to ongoing research and discussion. The traditional theory has been that hunters entered the Bering Land Bridge between eastern Siberia and present-day Alaska from 27,000 to 14,000 years ago. A growing viewpoint is that
7448-604: The mainland in Mexico. With local indigenous allies, the Spanish conquered the Aztec empire in central Mexico in 1521. Spain then established permanent cities in Mexico, Central America, and Spanish South America in the sixteenth century. Once Spaniards conquered the high civilization of the Aztecs and Incas, the Caribbean was a backwater of the Spanish empire. Other European powers began to intrude on areas claimed by Spain, including
7546-874: The middle into the main range of the Rockies and the coast ranges in California , Oregon , Washington , and British Columbia , with the Great Basin—a lower area containing smaller ranges and low-lying deserts—in between. The highest peak is Denali in Alaska. The U.S. Geographical Survey (USGS) states that the geographic center of North America is "6 miles [10 km] west of Balta, Pierce County, North Dakota " at about 48°10′N 100°10′W / 48.167°N 100.167°W / 48.167; -100.167 , about 24 kilometers (15 mi) from Rugby, North Dakota . The USGS further states that "No marked or monumented point has been established by any government agency as
7644-460: The most accurate service possible, thereby increasing availability of the service. These avionics systems will use ionospheric corrections broadcast by WAAS, or self-generated onboard dual frequency corrections, depending on which one is more accurate. Download coordinates as: North America North America is a continent in the Northern and Western Hemispheres . North America
7742-454: The name America to North America. In 1538, Gerardus Mercator used the term America on his world map of the entire Western Hemisphere . On his subsequent 1569 map , Mercator called North America "America or New India" ( America sive India Nova ). The Spanish Empire called its territories in North and South America "Las Indias", and the name given to the state body that oversaw the region
7840-493: The northernmost countries and territories of North America: the U.S., Bermuda , Canada, Greenland, and St. Pierre and Miquelon. Although the term does not refer to a unified region, Middle America includes Mexico, Central America, and the Caribbean. North America's largest countries by land area are Canada and the U.S., both of which have well-defined and recognized subregions. In Canada, these include (from east to west) Atlantic Canada , Central Canada , Canadian Prairies ,
7938-440: The northernmost extent of the island named Newfoundland , has provided unmistakable evidence of Norse settlement. Norse explorer Leif Erikson (c. 970–1020 CE) is thought to have visited the area. Erikson was the first European to make landfall on the continent (excluding Greenland). The Mayan culture was still present in southern Mexico and Guatemala when the Spanish conquistadors arrived, but political dominance in
8036-509: The probability of failure. In addition to lowering implementation costs by "piggybacking" on a planned satellite launch, this also allowed the signal to be broadcast from geostationary orbit , which meant a small number of satellites could cover all of North America. On July 10, 2003, the WAAS signal was activated for general aviation, covering 95% of the United States, and portions of Alaska offering 350 feet (110 m) minimums. On January 17, 2008, Alabama-based Hickok & Associates became
8134-605: The raised but relatively flat plateau of the Canadian Shield in the northeast; and the varied eastern region, which includes the Appalachian Mountains, the coastal plain along the Atlantic seaboard, and the Florida peninsula. Mexico, with its long plateaus and cordilleras , falls largely in the western region, although the eastern coastal plain does extend south along the Gulf. The western mountains are split in
8232-500: The region, and as such rainforest , monsoon , and savanna types can be found, with rains and high temperatures throughout the year. Notable North American fauna include the bison , black bear , jaguar , cougar , prairie dog , turkey , pronghorn , raccoon , coyote , and monarch butterfly . Notable plants that were domesticated in North America include tobacco , maize , squash , tomato , sunflower , blueberry , avocado , cotton , chile pepper , and vanilla . Laurentia
8330-400: The requirements for Category 1 ILS approaches, namely, three-dimensional position information down to 200 feet (60 m) above touchdown zone elevation. Software improvements, to be implemented by September 2008, significantly improve signal availability of vertical guidance throughout the CONUS and Alaska. Area covered by the 95% available LPV solution in Alaska improves from 62% to 86%. And in
8428-481: The requirements for accuracy will go undetected. Specifically, the probability is stated as 1×10, and is equivalent to no more than 3 seconds of bad data per year. This provides integrity information equivalent to or better than Receiver Autonomous Integrity Monitoring (RAIM). Availability is the probability that a navigation system meets the accuracy and integrity requirements. Before the advent of WAAS, GPS specifications allowed for system unavailability for as much as
8526-487: The results of the formation of Pangaea was the Appalachian Mountains , which formed some 480 mya, making it among the oldest mountain ranges in the world. When Pangaea began to rift around 200 mya, North America became part of Laurasia , before it separated from Eurasia as its own continent during the mid- Cretaceous period. The Rockies and other western mountain ranges began forming around this time from
8624-432: The runway centerline, making the implementation of a precision approach both difficult and very expensive. The ILS system is composed of 180 different transmitting antennas at each point built. For some time the FAA and NASA developed a much improved system, the microwave landing system (MLS). The entire MLS system for a particular approach was isolated in one or two boxes located beside the runway, dramatically reducing
8722-529: The table above, PRN is the satellite's actual Pseudo-Random Number code. NMEA is the satellite number sent by some receivers when outputting satellite information (NMEA = PRN - 87). The user segment is the GPS and WAAS receiver, which uses the information broadcast from each GPS satellite to determine its location and the current time, and receives the WAAS corrections from the Space segment. The two types of correction messages received (fast and slow) are used in different ways. The GPS receiver can immediately apply
8820-538: The user segment. The satellites also broadcast the same type of range information as normal GPS satellites, effectively increasing the number of satellites available for a position fix. The space segment currently consists of three commercial satellites: Eutelsat 117 West B , SES-15 , and Galaxy 30 . The original two WAAS satellites, named Pacific Ocean Region (POR) and Atlantic Ocean Region-West (AOR-W), were leased space on Inmarsat III satellites. These satellites ceased WAAS transmissions on July 31, 2007. With
8918-574: The year 2016. A third satellite was later added to the system. From March to November 2010, the FAA broadcast a WAAS test signal on a leased transponder on the Inmarsat-4 F3 satellite. The test signal was not usable for navigation, but could be received and was reported with the identification numbers PRN 133 (NMEA #46). In November 2010, the signal was certified as operational and made available for navigation. Following in orbit testing, Eutelsat 117 West B, broadcasting signal on PRN 131 (NMEA #44),
9016-549: Was called the Council of the Indies . The United Nations and its statistics division recognize North America as including three regions: Northern America, Central America , and the Caribbean . "Northern America" is a distinct term from "North America", excluding Central America, which itself may or may not include Mexico . In the limited context of regional trade agreements, the term is used to reference three nations: Canada,
9114-664: Was certified as operational and made available for navigation on March 27, 2018. The SES 15 satellite was launched on May 18, 2017, and following an in-orbit test of several months, was set operational on July 15, 2019. In 2018, a contract was awarded to place a WAAS L-band payload on the Galaxy 30 satellite. The satellite was successfully launched on August 15, 2020, and the WAAS transmissions were set operational on April 26, 2022, re-using PRN 135 (NMEA #48). After approximately three weeks with four active WAAS satellites, operational WAAS transmissions on Anik F1-R were ended on May 17, 2022. In
9212-817: Was in Jamestown, Virginia in 1607, followed by additional colonial establishments on the east coast from present-day Georgia in the south to Massachusetts in the north, forming the Thirteen Colonies of British America. The English did not establish settlements north or east of the St. Lawrence Valley in present-day Canada until after the conclusion of the American Revolutionary War . Britain's early settlements in present-day Canada included St. John's, Newfoundland in 1630 and Halifax, Nova Scotia in 1749. The first permanent French settlement
9310-499: Was in Quebec City, Quebec in 1608 Footprint (satellite) The footprint of a communications satellite is the ground area that its transponders offer coverage , and determines the satellite dish diameter required to receive each transponder's signal. There is usually a different map for each transponder (or group of transponders), as each may be aimed to cover different areas. Footprint maps usually show either
9408-747: Was jointly developed by the United States Department of Transportation (DOT) and the Federal Aviation Administration (FAA) as part of the Federal Radionavigation Program (DOT-VNTSC-RSPA-95-1/DOD-4650.5), beginning in 1994, to provide performance comparable to category 1 instrument landing system (ILS) for all aircraft possessing the appropriately certified equipment. Without WAAS, ionospheric disturbances, clock drift , and satellite orbit errors create too much error and uncertainty in
9506-402: Was possible with ground-based systems, which were often blocked by terrain of varying elevation. This enables pilots to safely fly at lower altitudes, not having to rely on ground-based systems. For unpressurized aircraft, this conserves oxygen and enhances safety. The above benefits create not only convenience, but also have the potential to generate significant cost savings. The cost to provide
9604-473: Was the first European to suggest that the Americas represented a landmass not then known to the Europeans. In 1507, Waldseemüller published a world map, and placed the word "America" on the continent of present-day South America. The continent north of present-day Mexico was then referred to as Parias. On a 1553 world map published by Petrus Apianus , North America was called "Baccalearum", meaning "realm of
#228771