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Wheel Chock
Wheel chocks (or chocks) are wedges of sturdy material placed closely against a vehicle's wheels to prevent accidental movement. Chocks are placed for safety in addition to setting the brakes. The bottom surface is sometimes coated in rubber to enhance grip with the ground. For ease of removal, a rope may be tied to the chock or a set of two chocks. One edge of the wedge has a concave profile to contour to the wheel and increase the force necessary to overrun the chock. Most commonly, chocks are seen on aircraft and train cars. Automobiles usually have parking brakes on the rear wheels. If the rear axle is jacked off the ground with only the parking brake set, the vehicle may roll on the front wheels and fall. Chocking the front wheels prevents this mishap. Motorcycle and bicycle chocks are bifurcated and fit around the wheel, supporting the bike and preventing its movement. The mining industry uses wheel chocks to protect lubrication trucks and heavy maintenance vehicles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chocks
Chock or Chocks may refer to: Devices for preventing movement * Wheel chock, tool to prevent accidental movement * Chock (climbing), anchor * Chock, component of a sailing block Other uses * Chock (surname) * ''Chock'' (TV series), a Swedish horror television series * Chock, a Swedish-language edition of Chill * Chocks, a children's multivitamin product made by Miles Laboratories See also * Choc (other) * Chok (other) * "''Chocky''", short story * Chock full o'Nuts Chock full o'Nuts is an American brand of coffee that originated from a chain of New York City coffee shops. Its unusual name derives from the 18 nut shops that founder William Black (c. 1902 – 1983) established under that banner in the city ..., coffee brand * Railway wheel stop {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wheel
A wheel is a circular component that is intended to rotate on an axle Bearing (mechanical), bearing. The wheel is one of the key components of the wheel and axle which is one of the Simple machine, six simple machines. Wheels, in conjunction with axles, allow heavy objects to be moved easily facilitating movement or transportation while supporting a load, or performing labor in machines. Wheels are also used for other purposes, such as a ship's wheel, steering wheel, potter's wheel, and flywheel. Common examples are found in transport applications. A wheel reduces friction by facilitating motion by rolling together with the use of Axle, axles. In order for wheels to rotate, a Moment (physics), moment needs to be applied to the wheel about its axis, either by way of gravity or by the application of another external force or torque. Using the wheel, Sumer, Sumerians invented a device that spins clay as a potter shapes it into the desired object. Terminology The English word '':wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brakes
A brake is a mechanical device that inhibits motion by absorbing energy from a moving system. It is used for slowing or stopping a moving vehicle, wheel, axle, or to prevent its motion, most often accomplished by means of friction. Background Most brakes commonly use friction between two surfaces pressed together to convert the kinetic energy of the moving object into heat, though other methods of energy conversion may be employed. For example, regenerative braking converts much of the energy to electrical energy, which may be stored for later use. Other methods convert kinetic energy into potential energy in such stored forms as pressurized air or pressurized oil. Eddy current brakes use magnetic fields to convert kinetic energy into electric current in the brake disc, fin, or rail, which is converted into heat. Still other braking methods even transform kinetic energy into different forms, for example by transferring the energy to a rotating flywheel. Brakes are generally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rope
A rope is a group of yarns, plies, fibres, or strands that are twisted or braided together into a larger and stronger form. Ropes have tensile strength and so can be used for dragging and lifting. Rope is thicker and stronger than similarly constructed cord, string, and twine. Construction Rope may be constructed of any long, stringy, fibrous material, but generally is constructed of certain natural or synthetic fibres. Synthetic fibre ropes are significantly stronger than their natural fibre counterparts, they have a higher tensile strength, they are more resistant to rotting than ropes created from natural fibres, and they can be made to float on water. But synthetic ropes also possess certain disadvantages, including slipperiness, and some can be damaged more easily by UV light. Common natural fibres for rope are Manila hemp, hemp, linen, cotton, coir, jute, straw, and sisal. Synthetic fibres in use for rope-making include polypropylene, nylon, polyesters (e.g. ... [...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 hot-air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parking Brake
In road vehicles, the parking brake, also known as a handbrake or emergency brake (e-brake), is a mechanism used to keep the vehicle securely motionless when parked. Parking brakes often consist of a cable connected to two wheel brakes, which is then connected to a pulling mechanism. In most vehicles, the parking brake operates only on the rear wheels, which have reduced traction while braking. The mechanism may be a hand-operated lever, a straight pull handle located near the steering column or a foot-operated pedal located with the other pedals. Overview While most automatic transmission vehicles have parking brakes, it is often not engaged by American drivers when parking. However, it is recommended to use it, as the parking pawl in the gearbox could fail due to stress or another vehicle striking the car, causing the car to roll. In manual transmission vehicles, the parking brake can be engaged to help keep the vehicle stationary. When parking on an uphill gradient, it is reco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parking Space
A parking space, parking place or parking spot is a location that is designated for parking, either paved or unpaved. It can be in a parking garage, in a parking lot or on a city street. The space may be delineated by road surface markings. The automobile fits inside the space, either by parallel parking, perpendicular parking or angled parking. Depending on the location of the parking space, the time allowed to park may be fixed by regulation, and a fee may be required to use the parking space. It may be designated for free parking. When the demand for spaces outstrips supply, vehicles may overspill park onto the sidewalk, grass verges and other places which were not designed for the purpose. Patterns For most motorised vehicles, there are three commonly used arrangements of parking spaces—parallel parking, perpendicular parking, and angle parking. These are self-park configurations where the vehicle driver is able to access the parking independently. Parallel pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concrete
Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most widely used building material. Its usage worldwide, ton for ton, is twice that of steel, wood, plastics, and aluminum combined. Globally, the ready-mix concrete industry, the largest segment of the concrete market, is projected to exceed $600 billion in revenue by 2025. This widespread use results in a number of environmental impacts. Most notably, the production process for cement produces large volumes of greenhouse gas emissions, leading to net 8% of global emissions. Other environmental concerns include widespread illegal sand mining, impacts on the surrounding environment such as increased surface runoff or urban heat island effect, and potential public health implications from toxic ingredients. Significant research and development is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Airways
British Airways (BA) is the flag carrier airline of the United Kingdom. It is headquartered in London London is the capital and List of urban areas in the United Kingdom, largest city of England and the United Kingdom, with a population of just under 9 million. It stands on the River Thames in south-east England at the head of a estuary dow ..., England, near its main Airline hub, hub at Heathrow Airport. The airline is the second largest UK-based carrier, based on fleet size and passengers carried, behind easyJet. In January 2011 BA merged with Iberia (airline), Iberia, creating the International Airlines Group (IAG), a holding company registered in Madrid, Spain. IAG is the world's third-largest airline group in terms of annual revenue and the second-largest in Europe. It is listed on the London Stock Exchange and in the FTSE 100 Index. British Airways is the first passenger airline to have generated more than US$1 billion on a single air route in a year (from 1 Apr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airbus A321
The Airbus A321 is a member of the Airbus A320 family of short to medium range, narrow-body, commercial passenger twin engine jet airliners; it carries 185 to 236 passengers. It has a stretched fuselage which was the first derivative of the baseline A320 and entered service in 1994, about six years after the original A320. The aircraft shares a common type rating with all other Airbus A320-family variants, allowing previous A320-family pilots to fly the aircraft without the need for further training. In December 2010, Airbus announced a new generation of the A320 family, the A320neo (new engine option). The similarly lengthened fuselage A321neo variant offers new, more efficient engines, combined with airframe improvements and the addition of winglets (called ''Sharklets'' by Airbus). The aircraft delivers fuel savings of up to 15%. The A321neo carries up to 244 passengers, with a maximum range of for the long-range version when carrying no more than 206 passengers. Final ass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airman
An airman is a member of an air force or air arm of a nation's armed forces. In certain air forces, it can also refer to a specific enlisted rank. An airman can also be referred as a soldier in other definitions. In civilian aviation usage, the term airman is analogous to the term ''sailor'' in nautical usage. In the American Federal Aviation Administration usage, an airman is any holder of an airman's certificate, male or female. This certificate is issued to those who qualify for it by the Federal Aviation Administration Airmen Certification Branch. United States Air Force In the U.S. Air Force, airman is a general term which can refer to any member of the United States Air Force, regardless of rank, but is also a specific enlisted rank in the Air Force. The rank of airman (abbreviated "Amn") is the second enlisted rank from the bottom, just above the rank of Airman Basic, and just below that of Airman First Class. Since the Air Force was established in 1947, all of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
F-117 Nighthawk
The Lockheed F-117 Nighthawk is a retired American single-seat, twin-engine stealth attack aircraft developed by Lockheed's secretive Skunk Works division and operated by the United States Air Force (USAF). It was the first operational aircraft to be designed with stealth technology. The F-117 was based on the ''Have Blue'' technology demonstrator. The Nighthawk's maiden flight took place in 1981 at Groom Lake, Nevada, and the aircraft achieved initial operating capability status in 1983. The aircraft was shrouded in secrecy until it was revealed to the public in 1988. Of the 64 F-117s built, 59 were production versions, with the other five being prototypes. The F-117 was widely publicized for its role in the Gulf War of 1991. Although it was commonly referred to as the "Stealth Fighter", it was strictly an attack aircraft. F-117s took part in the conflict in Yugoslavia, where one was shot down by a surface-to-air missile (SAM) in 1999. The U.S. Air Force retired the F-117 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
