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Emergency Flotation System
Emergency Flotation Systems (EFS) are emergency systems installed on larger commercial and military helicopters in order to prevent the airframe sinking in the event of a crash landing on water. The floats may be packed within spaces inside the airframe or as externally mounted packs on the helicopter skids. The floats are inflated using gas stored in pressurised cylinders carried on board the helicopter. History By 1979, United States Navy and Marine Corps Boeing Vertol CH-46 Sea Knight helicopters had been involved in 64 emergency landings in water. Of the 64, 47 helicopters sunk after landing, killing 75. A study estimated 50% of those fatalities could have been prevented had the helicopters been equipped with adequate emergency flotation. Because helicopters tend to have a high center of gravity due to the high-mounted engine and transmission, even if they are naturally buoyant in the water with hatches secured, they will tend to overturn in heavy sea conditions. Regulation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicopter
A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of STOL (Short TakeOff and Landing) or STOVL (Short TakeOff and Vertical Landing) aircraft cannot perform without a runway. In 1942, the Sikorsky R-4 became the first helicopter to reach full-scale production.Munson 1968.Hirschberg, Michael J. and David K. Dailey"Sikorsky". ''US and Russian Helicopter Development in the 20th Century'', American Helicopter Society, International. 7 July 2000. Although most earlier designs used more than one main rotor, the configuration of a single main rotor accompanied by a vertical anti-torque tail rotor (i.e. unicopter, not to be confused with the single-blade monocopter) has become the most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airframe
The mechanical structure of an aircraft is known as the airframe. This structure is typically considered to include the fuselage, undercarriage, empennage and wings, and excludes the propulsion system. Airframe design is a field of aerospace engineering that combines aerodynamics, materials technology and manufacturing methods with a focus on weight, strength and aerodynamic drag, as well as reliability and cost.Michael C. Y. Niu (1988). ''Airframe Structural Design''. Conmilit Press LTD. History Modern airframe history began in the United States when a 1903 wood biplane made by Orville and Wilbur Wright showed the potential of fixed-wing designs. In 1912 the Deperdussin Monocoque pioneered the light, strong and streamlined monocoque fuselage formed of thin plywood layers over a circular frame, achieving . First World War Many early developments were spurred by military needs during World War I. Well known aircraft from that era include the Dutch desig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicopter Skids
A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of STOL (Short TakeOff and Landing) or STOVL (Short TakeOff and Vertical Landing) aircraft cannot perform without a runway. In 1942, the Sikorsky R-4 became the first helicopter to reach full-scale production.Munson 1968.Hirschberg, Michael J. and David K. Dailey"Sikorsky". ''US and Russian Helicopter Development in the 20th Century'', American Helicopter Society, International. 7 July 2000. Although most earlier designs used more than one main rotor, the configuration of a single main rotor accompanied by a vertical anti-torque tail rotor (i.e. unicopter, not to be confused with the single-blade monocopter) has become the most com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of its active battle fleet alone exceeding the next 13 navies combined, including 11 allies or partner nations of the United States as of 2015. It has the highest combined battle fleet tonnage (4,635,628 tonnes as of 2019) and the world's largest aircraft carrier fleet, with eleven in service, two new carriers under construction, and five other carriers planned. With 336,978 personnel on active duty and 101,583 in the Ready Reserve, the United States Navy is the third largest of the United States military service branches in terms of personnel. It has 290 deployable combat vessels and more than 2,623 operational aircraft . The United States Navy traces its origins to the Continental Navy, which was established during the American Re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Marine Corps
The United States Marine Corps (USMC), also referred to as the United States Marines, is the maritime land force service branch of the United States Armed Forces responsible for conducting expeditionary and amphibious operations through combined arms, implementing its own infantry, artillery, aerial, and special operations forces. The U.S. Marine Corps is one of the eight uniformed services of the United States. The Marine Corps has been part of the U.S. Department of the Navy since 30 June 1834 with its sister service, the United States Navy. The USMC operates installations on land and aboard sea-going amphibious warfare ships around the world. Additionally, several of the Marines' tactical aviation squadrons, primarily Marine Fighter Attack squadrons, are also embedded in Navy carrier air wings and operate from the aircraft carriers. The history of the Marine Corps began when two battalions of Continental Marines were formed on 10 November 1775 in Philadelphia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing Vertol CH-46 Sea Knight
The Boeing Vertol CH-46 Sea Knight is a medium-lift tandem-rotor transport helicopter powered by twin turboshaft engines. It was designed by Vertol and manufactured by Boeing Vertol following Vertol's acquisition by Boeing. Development of the Sea Knight, which was originally designated by the firm as the Vertol Model 107, commenced during 1956. It was envisioned as a successor to the first generation of rotorcraft, such as the H-21 "Flying Banana", that had been powered by piston engines; in its place, the V-107 made use of the emergent turboshaft engine. On 22 April 1958, the V-107 prototype performed its maiden flight. During June 1958, the US Army awarded a contract for the construction of ten production-standard aircraft, designated as the YHC-1A, based on the V-107; this initial order was later cut down to three YHC-1As though. During 1961, the US Marine Corps (USMC), which had been studying its requirements for a medium-lift, twin-turbine cargo/troop assault helic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Federal Aviation Regulations
The Federal Aviation Regulations (FARs) are rules prescribed by the Federal Aviation Administration (FAA) governing all aviation activities in the United States. The FARs comprise Title 14 of the Code of Federal Regulations (CFR). A wide variety of activities are regulated, such as aircraft design and maintenance, typical airline flights, pilot training activities, hot-air ballooning, lighter-than-air aircraft, man-made structure heights, obstruction lighting and marking, model rocket launches, commercial space operations, model aircraft operations, Unmanned Aircraft Systems (UAS) and kite flying. The rules are designed to promote safe aviation, protecting pilots, flight attendants, passengers and the general public from unnecessary risk. FAR vs. 14 CFR Since 1958, these rules have typically been referred to as "FARs", short for Federal Aviation Regulations. However, another set of regulations (Title 48) is titled "Federal Acquisitions Regulations", and this has led to con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Advisory Circular
__NOTOC__ Advisory circular (AC) refers to a type of publication offered by the Federal Aviation Administration (FAA) to provide guidance for compliance with airworthiness regulations, pilot certification, operational standards, training standards, and any other rules within the 14 CFR Aeronautics and Space Title. They define acceptable means, but not the only means, of accomplishing or showing compliance with airworthiness regulations. Generally informative in nature, Advisory Circulars are neither binding nor regulatory; yet some have the effect of ''de facto'' standards or regulations. Advisory circulars typically refer to industry standards from SAE (ARP) and RTCA (DO). With harmonization of technical content and guidance between EASA and the FAA, later advisory circulars also identify corresponding EUROCAE (ED) publications. Some advisory circulars are only a few pages long and do little more than reference a recommended standard; for example, AC 20-152 referencing DO ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helium
Helium (from el, ἥλιος, helios, lit=sun) is a chemical element with the symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table. Its boiling and melting point are the lowest among all the elements. It is the second lightest and second most abundant element in the observable universe (hydrogen is the lightest and most abundant). It is present at about 24% of the total elemental mass, which is more than 12 times the mass of all the heavier elements combined. Its abundance is similar to this in both the Sun and in Jupiter, due to the very high nuclear binding energy (per nucleon) of helium-4, with respect to the next three elements after helium. This helium-4 binding energy also accounts for why it is a product of both nuclear fusion and radioactive decay. The most common isotope of helium in the universe is helium-4, the vast majority of which was formed during t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen
Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh in total abundance in the Milky Way and the Solar System. At standard temperature and pressure, two atoms of the element bond to form N2, a colorless and odorless diatomic gas. N2 forms about 78% of Earth's atmosphere, making it the most abundant uncombined element. Nitrogen occurs in all organisms, primarily in amino acids (and thus proteins), in the nucleic acids ( DNA and RNA) and in the energy transfer molecule adenosine triphosphate. The human body contains about 3% nitrogen by mass, the fourth most abundant element in the body after oxygen, carbon, and hydrogen. The nitrogen cycle describes the movement of the element from the air, into the biosphere and organic compounds, then back into the atmosphere. Many industrially ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
