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Pitot Tube
A pitot tube ( ; also pitot probe) measures fluid flow velocity. It was invented by French engineer Henri Pitot during his work with aqueducts and published in 1732, and modified to its modern form in 1858 by Henry Darcy. It is widely used to determine the airspeed of aircraft; the water speed of boats; and the flow velocity of liquids, air, and gases in industry. Theory of operation The basic pitot tube consists of a tube pointing directly into the oncoming fluid flow. Pressure in the tube can be measured as the moving fluid cannot escape and stagnates. This pressure is the stagnation pressure of the fluid, also known as the total pressure or (particularly in aviation) the pitot pressure. The measured stagnation pressure cannot just by itself be used to determine the fluid flow velocity (airspeed in aviation) directly. However, with a measured static pressure as well it can be determined by the use of Bernoulli's equation which states: :Stagnation pressure = static pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airspeed P1230157
In aviation, airspeed is the speed of an aircraft relative to the air it is flying through (which itself is usually moving relative to the ground due to wind). In contrast, the ground speed is the speed of an aircraft with respect to the surface of the Earth (whether over land or presumed-stationary water). It is difficult to measure the exact airspeed of the aircraft (true airspeed), but other measures of airspeed, such as indicated airspeed and Mach number give useful information about the capabilities and limitations of airplane performance. The common measures of airspeed are: * Indicated airspeed (IAS), what is read on an airspeed gauge connected to a pitot-static system. * Calibrated airspeed (CAS), indicated airspeed adjusted for pitot system position and installation error. * True airspeed (TAS) is the actual speed the airplane is moving through the air. When combined with aircraft direction, wind speed and direction, it can be used to calculate ground speed and direct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indicated Airspeed
Indicated airspeed (IAS) is the airspeed of an aircraft as measured by its pitot-static system and displayed by the airspeed indicator (ASI). This is the pilots' primary airspeed reference. This value is not corrected for installation error, instrument error, or the actual encountered air density, being instead calibrated to always reflect the adiabatic compressible flow of the International Standard Atmosphere at sea level. It uses the difference between total pressure and static pressure, provided by the system, to either mechanically or electronically measure dynamic pressure. The dynamic pressure includes terms for both density and airspeed. Since the airspeed indicator cannot know the density, it is by design calibrated to assume the sea level standard atmospheric density when calculating airspeed. Since the actual density will vary considerably from this assumed value as the aircraft changes altitude, IAS varies considerably from true airspeed (TAS), the relative ve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bureau D'Enquêtes Et D'Analyses Pour La Sécurité De L'Aviation Civile
The Bureau of Enquiry and Analysis for Civil Aviation Safety (, BEA) is an agency of the French government, responsible for investigating aviation accidents and incidents and making safety recommendations based on what is learned from those investigations. Its headquarters are at Paris–Le Bourget Airport in Le Bourget, near Paris. The BEA has 96 employees in 2019, including 30 investigators and 12 investigative assistants."Who are we? " Bureau d'Enquêtes et d'Analyses pour la sécurité de l'aviation civile. Retrieved on 8 June 2009. It is under the authority of the Ministry of Ecology, Sustainable Development, Transport and Housing. The B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-31
The Rockwell-Messerschmitt-Bölkow-Blohm X-31 is an experimental jet aircraft designed to test fighter thrust vectoring technology. It was designed and built by Rockwell and Messerschmitt-Bölkow-Blohm (MBB), as part of a joint United States and German ''Enhanced Fighter Maneuverability'' program to provide additional control authority in pitch and yaw, for significantly more maneuverability than most conventional fighters. An advanced flight control system provided controlled flight at high angles of attack where conventional aircraft would stall or lose control. Two aircraft were built, of which one has survived. Design and development As the first international X-plane program, the Defense Advanced Research Projects Agency (DARPA) was the US Government's top-level management, with the US Navy serving as the military agent through Naval Air Systems Command ( NAVAIR). NASA supported the X-31 program through its Langley Research Center and Dryden Flight Research Center. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birgenair Flight 301
Birgenair Flight 301 was a flight chartered by Turkish-managed Birgenair partner Alas Nacionales from San Felipe de Puerto Plata, Puerto Plata in the Dominican Republic to Frankfurt, Germany, via Gander, Newfoundland and Labrador, Gander, Canada, and Berlin, Germany. On 6 February 1996, the Boeing 757-200 operating the route crashed shortly after take-off from Puerto Plata's Gregorio Luperón International Airport, killing all 189 people on board. The cause was pilot error after receiving incorrect airspeed information from one of the pitot tubes, which investigators believe was blocked by a Sphecidae, wasp nest built inside it. The aircraft had been sitting unused for 20 days, and without Remove before flight, pitot tube covers in place for the two days preceding the crash. Flight 301 is tied with American Airlines Flight 77 as the deadliest aviation incident involving a Boeing 757, having a total of 189 fatalities. Furthermore, Flight 301 is the deadliest aviation accident eve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northwest Airlines Flight 6231
Northwest Orient Airlines Flight 6231 was the fatal crash of a Boeing 727 in the eastern United States on December 1, 1974 in Harriman State Park near Stony Point, New York, just north of the New York City area. The Northwest Airlines 727 had been chartered to pick up the Baltimore Colts professional football team in Buffalo in western New York. All three crew members on board died when the aircraft struck the ground following a stall and rapid descent caused by the crew's reaction to erroneous airspeed readings caused by atmospheric icing. The icing occurred due to failure to turn on the pitot tube heating at the start of the flight. This was one of two Boeing 727s to crash in the eastern U.S. that day; the other was TWA Flight 514 in northern Virginia, northwest of Dulles airport ( to the southwest). Aircraft The Boeing 727-251, registration N274US, was certificated and maintained in accordance with FAA regulations and requirements at the time of the crash. Copy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Austral Líneas Aéreas Flight 2553
Austral Líneas Aéreas Flight 2553 was an Argentine domestic scheduled passenger flight from Posadas to Buenos Aires. On October 10, 1997, the McDonnell Douglas DC-9-32 that was operating the flight crashed on the lands of Estancia Magallanes, Nuevo Berlín, away from Fray Bentos, Uruguay. All 74 passengers and crew died upon impact. The accident remains the deadliest in Uruguayan history. Background Aircraft The aircraft involved was a McDonnell Douglas DC-9-32, registration LV-WEG. It had its maiden flight in 1969, and as of the time of the accident had flown a total of 56,854 hours and 54,800 takeoff and landing cycles. Crew The captain was 40-year-old Jorge Cécere, who had been with the airline since 1989 and logged 9,238 hours, including 223 hours on the DC-9. The first officer was Horacio Núñez, who was also 40. He had been with the airline since 1993 and had 2,910 flight hours. He was more experienced on the DC-9 than Captain Cécere, with 1,384 hours o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertical Speed Indicator
In aviation, a variometer – also known as a rate of climb and descent indicator (RCDI), rate-of-climb indicator, vertical speed indicator (VSI), or vertical velocity indicator (VVI) – is one of the flight instruments in an aircraft used to inform the pilot of the rate of descent or climb.Federal Aviation Administration, ''Glider Flying Handbook'', Skyhorse Publishing Inc., 2007 pages 4-7 and 4-8 It can be calibrated in metres per second, feet per minute (1 ft/min = 0.00508 m/s) or knots (1 kn ≈ 0.514 m/s), depending on country and type of aircraft. It is typically connected to the aircraft's external static pressure source. In powered flight, the pilot makes frequent use of the VSI to ascertain that level flight is being maintained, especially during turning maneuvers. In gliding, the instrument is used almost continuously during normal flight, often with an audible output, to inform the pilot of rising or sinking air. It is usual for gliders to b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Altitude
Altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum (geodesy), datum and a point or object. The exact definition and reference datum varies according to the context (e.g., aviation, geometry, geographical survey, sport, or atmospheric pressure). Although the term ''altitude'' is commonly used to mean the height above sea level of a location, in geography the term elevation is often preferred for this usage. In aviation, altitude is typically measured relative to mean sea level or above ground level to ensure safe navigation and flight operations. In geometry and geographical surveys, altitude helps create accurate topographic maps and understand the terrain's elevation. For high-altitude trekking and sports, knowing and adapting to altitude is vital for performance and safety. Higher altitudes mean reduced oxygen levels, which can lead to altitude sickness if proper acclimatization measures are not taken. Vertical distance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mach Number
The Mach number (M or Ma), often only Mach, (; ) is a dimensionless quantity in fluid dynamics representing the ratio of flow velocity past a boundary to the local speed of sound. It is named after the Austrian physicist and philosopher Ernst Mach. \mathrm = \frac, where: * is the local Mach number, * is the local flow velocity with respect to the boundaries (either internal, such as an object immersed in the flow, or external, like a channel), and * is the speed of sound in the medium, which in air varies with the square root of the thermodynamic temperature. By definition, at Mach1, the local flow velocity is equal to the speed of sound. At Mach0.65, is 65% of the speed of sound (subsonic), and, at Mach1.35, is 35% faster than the speed of sound (supersonic). The local speed of sound, and hence the Mach number, depends on the temperature of the surrounding gas. The Mach number is primarily used to determine the approximation with which a flow can be treated as an i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
System
A system is a group of interacting or interrelated elements that act according to a set of rules to form a unified whole. A system, surrounded and influenced by its open system (systems theory), environment, is described by its boundaries, structure and purpose and is expressed in its functioning. Systems are the subjects of study of systems theory and other systems sciences. Systems have several common properties and characteristics, including structure, function(s), behavior and interconnectivity. Etymology The term ''system'' comes from the Latin word ''systēma'', in turn from Greek language, Greek ''systēma'': "whole concept made of several parts or members, system", literary "composition"."σύστημα" , Henry George Liddell, Robert Scott, ''A Greek–English Lexicon'', on Pers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standard Gravity
The standard acceleration of gravity or standard acceleration of free fall, often called simply standard gravity and denoted by or , is the nominal gravitational acceleration of an object in a vacuum near the surface of the Earth. It is a constant defined by standard as . This value was established by the third General Conference on Weights and Measures (1901, CR 70) and used to define the standard weight of an object as the product of its mass and this nominal acceleration. The acceleration of a body near the surface of the Earth is due to the combined effects of gravity and centrifugal acceleration from the rotation of the Earth (but the latter is small enough to be negligible for most purposes); the total (the apparent gravity) is about 0.5% greater at the poles than at the Equator. Although the symbol is sometimes used for standard gravity, (without a suffix) can also mean the local acceleration due to local gravity and centrifugal acceleration, which varies depending on on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
