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Powerback
Powerback is used by aircraft to move backwards on the ground using the power of their engines along with the aircraft's thrust reversal. Propeller driven (turboprop) aircraft tend to use powerbacks as a means of reversing; powerbacking is often prohibited by the manufacturer on jet aircraft (with the exception of some jet aircraft with tail mounted engines). Background While many aircraft are physically capable of performing powerbacks, many companies impose restrictions on the practice, mainly due to the risk of FOD (foreign object damage) from debris propelled into the air. This problem is magnified even more with planes having wing-mounted engines, as their proximity to the ground can exacerbate debris ingestion if powerbacks are used. Small metal objects are particularly dangerous as they can be propelled into terminal windows, employees on the ground or even the aircraft itself. Applying the brakes when backing up also has the potential to cause a tailstrike. During the 1980s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines. Common examples of aircraft include airplanes, helicopters, airships (including blimps), gliders, paramotors, and hot air balloons. The human activity that surrounds aircraft is called ''aviation''. The science of aviation, including designing and building aircraft, is called '' aeronautics.'' Crewed aircraft are flown by an onboard pilot, but unmanned aerial vehicles may be remotely controlled or self-controlled by onboard computers. Aircraft may be classified by different criteria, such as lift type, aircraft propulsion, usage and others. History Flying model craft and stories of manned flight go back many centuries; however, the first manned ascent — and safe descent — in modern times took place by larger h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northwest Airlines
Northwest Airlines Corp. (NWA) was a major American airline founded in 1926 and absorbed into Delta Air Lines, Inc. by a merger. The merger, approved on October 29, 2008, made Delta the largest airline in the world until the American Airlines-US Airways merger on December 9, 2013. Northwest continued to operate under its own name and brand until the integration of the carriers was completed on January 31, 2010. Northwest was headquartered in Eagan, Minnesota near Minneapolis-St. Paul International Airport. After World War II it became dominant in the trans-Pacific market with a hub in Tokyo, Japan (initially Haneda Airport, later Narita International Airport). In response to United Airlines's 1985 acquisition of Pan Ams' Pacific routes, Northwest paid $884 million to purchase Republic Airlines and then established fortress hubs at Detroit Metropolitan Wayne County Airport and Memphis International Airport. With this merger, NWA established the domestic network necessary to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrust Reversal
Thrust reversal, also called reverse thrust, is the temporary diversion of an aircraft engine's thrust for it to act against the forward travel of the aircraft, providing deceleration. Thrust reverser systems are featured on many jet aircraft to help slow down just after touch-down, reducing wear on the brakes and enabling shorter landing distances. Such devices affect the aircraft significantly and are considered important for safe operations by airlines. There have been accidents involving thrust reversal systems, including fatal ones. Reverse thrust is also available on many propeller-driven aircraft through reversing the controllable-pitch propellers to a negative angle. The equivalent concept for a ship is called astern propulsion. Principle and uses A landing roll consists of touchdown, bringing the aircraft to taxi speed, and eventually to a complete stop. However, most commercial jet engines continue to produce thrust in the forward direction, even when idle, acti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxiing
Taxiing (rarely spelled taxying) is the movement of an aircraft on the ground, under its own power, in contrast to towing or pushback where the aircraft is moved by a tug. The aircraft usually moves on wheels, but the term also includes aircraft with skis or floats (for water-based travel). An airplane uses taxiways to taxi from one place on an airport to another; for example, when moving from a hangar to the runway. The term "taxiing" is not used for the accelerating run along a runway prior to takeoff, or the decelerating run immediately after landing, which are called the takeoff roll and landing rollout, respectively. Etymology As early as 1909 aviation journalists envisioned aeroplanes to replace the taxicab in traffic-congested cities. Some aviators and some linguists report that around the year 1911 the slang word "taxi" was in use for an "airplane". They suggest that the way aircraft move under power before they take off or after they land reminded someone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pushback
In aviation, pushback is an airport procedure during which an aircraft is pushed backwards away from its parking position, usually at an airport gate by external power. Pushbacks are carried out by special, low-profile vehicles called ''pushback tractors'' or ''tugs''. Although many aircraft are capable of moving themselves backwards on the ground using reverse thrust (a procedure referred to as a ''powerback),'' the resulting jet blast or prop wash would cause increased noise, damage to the terminal building or equipment, and hurt airport staff due to high-speed debris. This debris would also be sucked into the engine, as it is in normal use, and cause excessive wear - a major cause of wear on aircraft engines is during ground use. A pushback is therefore the preferred method when ground-handling aircraft. Definition IATA defines aircraft pushback as "rearward moving of an aircraft from a parking position to a taxi position by use of specialized ground support equipment." Pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C-17 Globemaster III
The McDonnell Douglas/Boeing C-17 Globemaster III is a large military transport aircraft that was developed for the United States Air Force (USAF) from the 1980s to the early 1990s by McDonnell Douglas. The C-17 carries forward the name of two previous piston-engined military cargo aircraft, the Douglas C-74 Globemaster and the Douglas C-124 Globemaster II. The C-17 is based upon the YC-15, a smaller prototype airlifter designed during the 1970s. It was designed to replace the Lockheed C-141 Starlifter, and also fulfill some of the duties of the Lockheed C-5 Galaxy. Compared to the YC-15, the redesigned airlifter differed in having swept wings, increased size, and more powerful engines. Development was protracted by a series of design issues, causing the company to incur a loss of nearly US$1.5 billion on the program's development phase. On 15 September 1991, roughly one year behind schedule, the first C-17 performed its maiden flight. The C-17 formally entered USAF servic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C-5 Galaxy
The Lockheed C-5 Galaxy is a large military transport aircraft designed and built by Lockheed, and now maintained and upgraded by its successor, Lockheed Martin. It provides the United States Air Force (USAF) with a heavy intercontinental-range strategic airlift capability, one that can carry outsized and oversized loads, including all air-certifiable cargo. The Galaxy has many similarities to the smaller Lockheed C-141 Starlifter and the later Boeing C-17 Globemaster III. The C-5 is among the largest military aircraft in the world. The C-5 Galaxy's development was complicated, including significant cost overruns, and Lockheed suffered significant financial difficulties. Shortly after entering service, cracks in the wings of many aircraft were discovered and the C-5 fleet was restricted in capability until corrective work was completed. The C-5M Super Galaxy is an upgraded version with new engines and modernized avionics designed to extend its service life to 2040 and beyon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C-130 Hercules
The Lockheed C-130 Hercules is an American four-engine turboprop military transport aircraft designed and built by Lockheed (now Lockheed Martin). Capable of using unprepared runways for takeoffs and landings, the C-130 was originally designed as a troop, medevac, and cargo transport aircraft. The versatile airframe has found uses in other roles, including as a gunship (AC-130), for airborne assault, search and rescue, scientific research support, weather reconnaissance, aerial refueling, maritime patrol, and aerial firefighting. It is now the main tactical airlifter for many military forces worldwide. More than 40 variants of the Hercules, including civilian versions marketed as the Lockheed L-100, operate in more than 60 nations. The C-130 entered service with the U.S. in 1956, followed by Australia and many other nations. During its years of service, the Hercules has participated in numerous military, civilian and humanitarian aid operations. In 2007, the C-130 beca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Federal Aviation Administration
The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic management, certification of personnel and aircraft, setting standards for airports, and protection of U.S. assets during the launch or re-entry of commercial space vehicles. Powers over neighboring international waters were delegated to the FAA by authority of the International Civil Aviation Organization. Created in , the FAA replaced the former Civil Aeronautics Administration (CAA) and later became an agency within the U.S. Department of Transportation. Major functions The FAA's roles include: *Regulating U.S. commercial space transportation *Regulating air navigation facilities' geometric and flight inspection standards *Encouraging and developing civil aeronautics, including new aviation technology *Issuing, suspending, or revoki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
McDonnell Douglas MD-80
The McDonnell Douglas MD-80 is a series of five-abreast single-aisle airliners developed by McDonnell Douglas. It was produced by the developer company until August 1997 and then by Boeing Commercial Airplanes. The MD-80 was the second generation of the DC-9 family, originally designated as the DC-9-80 (DC-9 Series 80) and later stylized as the DC-9 Super 80 (short ''Super 80''). Stretched, enlarged wing and powered by higher bypass Pratt & Whitney JT8D-200 engines, the aircraft program was launched in October 1977. The MD-80 made its first flight on October 18, 1979 as the Super 80 and was certified on August 25, 1980. The first airliner was delivered to launch customer Swissair on September 13, 1980, which introduced it into commercial service on October 10, 1980. Keeping the fuselage cross-section, longer variants are stretched by 14 ft (4.3 m) from the DC-9-50 and have a 28% larger wing. The larger variants (MD-81/82/83/88) are 148 ft (45.1 m) long to sea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Power (physics)
In physics, power is the amount of energy transferred or converted per unit time. In the International System of Units, the unit of power is the watt, equal to one joule per second. In older works, power is sometimes called ''activity''. Power is a scalar quantity. Power is related to other quantities; for example, the power involved in moving a ground vehicle is the product of the aerodynamic drag plus traction force on the wheels, and the velocity of the vehicle. The output power of a motor is the product of the torque that the motor generates and the angular velocity of its output shaft. Likewise, the power dissipated in an electrical element of a circuit is the product of the current flowing through the element and of the voltage across the element. Definition Power is the rate with respect to time at which work is done; it is the time derivative of work: P =\frac where is power, is work, and is time. If a constant force F is applied throughout a distance x, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing 727s
The Boeing 727 is an American narrow-body airliner that was developed and produced by Boeing Commercial Airplanes. After the heavy 707 quad-jet was introduced in 1958, Boeing addressed the demand for shorter flight lengths from smaller airports. On December 5, 1960, the 727 was launched with 40 orders each from United Airlines and Eastern Air Lines. The first 727-100 rolled out November 27, 1962, first flew on February 9, 1963, and entered service with Eastern on February 1, 1964. The only trijet aircraft to be produced by Boeing, the 727 is powered by Pratt & Whitney JT8D low-bypass turbofans below a T-tail, one on each side of the rear fuselage and a center one fed through an S-duct. It shares its six-abreast upper fuselage cross-section and cockpit with the 707. The long 727-100 typically carries 106 passengers in two classes over , or 129 in a single class. Launched in 1965, the stretched 727-200 flew in July 1967 and entered service with Northeast Airlines that Dece ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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