A composite material (also called a composition material or shortened to composite , which is the common name) is a material which is produced from two or more constituent materials. These constituent materials have notably dissimilar chemical or physical properties and are merged to create a material with properties unlike the individual elements. Within the finished structure, the individual elements remain separate and distinct, distinguishing composites from mixtures and solid solutions . Composite materials with more than one distinct layer are called composite laminates .
108-486: H47 may refer to : Boeing-Vertol H-47 Chinook , an American helicopter HMS Blanche (H47) , a Royal Navy B-class destroyer HMS H47 , a Royal Navy H-class submarine Hyampom Airport , in Trinity County, California, United States [REDACTED] Topics referred to by the same term This disambiguation page lists articles associated with
216-669: A fast rope -rappelling system, and other upgrades. The MH-47D was used by U.S. Army 160th Special Operations Aviation Regiment . Twelve MH-47D helicopters were produced. Six were converted from CH-47As and six were converted from CH-47C models. The MH-47E has been used by U.S. Army Special Operations. Beginning with the E-model prototype manufactured in 1991, a total of 26 Special Operations Aircraft were produced. All aircraft were assigned to 2–160th SOAR(A) "Nightstalkers", home based at Fort Campbell, Kentucky . E models were converted from CH-47C airframes. The MH-47E has similar capabilities as
324-421: A former ), continuous casting , filament winding , press moulding, transfer moulding , pultrusion moulding, and slip forming . There are also forming capabilities including CNC filament winding, vacuum infusion, wet lay-up, compression moulding , and thermoplastic moulding, to name a few. The practice of curing ovens and paint booths is also required for some projects. The composite parts finishing
432-547: A CH-47 while taxiing. Another had a retention pin shake loose on a 20 mm cannon and was brought down when its own gun fired through the forward rotor blades. The third was grounded by enemy fire and destroyed by enemy mortar rounds after the crew escaped. During the 1970s, the United States and Iran had a strong relationship, in which the Iranian armed forces began to use many American military aircraft, most notably
540-723: A Chinook that was shot down near Kabul in Kunar Province in June 2005 with all aboard killed, including a 16-member U.S. Special Operations team. Chinook helicopters participated in the 2021 Kabul airlift at the close of military operations in Afghanistan. The Chinook's ability to carry large, underslung loads has been of significant value in relief operations in the aftermath of natural disasters . Numerous operators have chosen to deploy their Chinook fleets to support humanitarian efforts in stricken nations overseas. Following
648-413: A central core of end grain balsa wood , bonded to surface skins of light alloy or GRP. These generate low-weight, high rigidity materials. Particulate composites have particle as filler material dispersed in matrix, which may be nonmetal, such as glass, epoxy. Automobile tire is an example of particulate composite. Advanced diamond-like carbon (DLC) coated polymer composites have been reported where
756-551: A chemical reaction) into a rigid structure. Usually, the operation is done in an open or closed forming mould. However, the order and ways of introducing the constituents alters considerably. Composites fabrication is achieved by a wide variety of methods, including advanced fibre placement (automated fibre placement), fibreglass spray lay-up process , filament winding , lanxide process , tailored fibre placement , tufting , and z-pinning . The reinforcing and matrix materials are merged, compacted, and cured (processed) within
864-696: A co-curing or post-curing of the prepreg with many other media, such as foam or honeycomb. Generally, this is known as a sandwich structure . This is a more general layup for the production of cowlings, doors, radomes or non-structural parts. Open- and closed-cell-structured foams like polyvinyl chloride , polyurethane , polyethylene , or polystyrene foams, balsa wood , syntactic foams , and honeycombs are generally utilized core materials. Open- and closed-cell metal foam can also be utilized as core materials. Recently, 3D graphene structures ( also called graphene foam) have also been employed as core structures. A recent review by Khurram and Xu et al., have provided
972-699: A contract for fifteen extensively modified and upgraded CH-47Fs for the Canadian Forces , later delivered in 2013–2014 with the Canadian designation CH-147F. On 15 December 2009, Britain announced its Future Helicopter Strategy, including the purchase of twenty-four new CH-47Fs to be delivered from 2012. Australia ordered seven CH-47Fs in March 2010 to replace its six CH-47Ds between 2014 and 2017. In September 2015, India approved purchase of fifteen CH-47F Chinooks. On 7 November 2016, Singapore announced that
1080-1192: A digital automated flight control system. Composite material Typical engineered composite materials include: There are various reasons where new material can be favoured. Typical examples include materials which are less expensive, lighter, stronger or more durable when compared with common materials, as well as composite materials inspired from animals and natural sources with low carbon footprint. More recently researchers have also begun to actively include sensing, actuation, computation, and communication into composites, which are known as robotic materials . Composite materials are generally used for buildings , bridges , and structures such as boat hulls , swimming pool panels, racing car bodies, shower stalls, bathtubs , storage tanks , imitation granite , and cultured marble sinks and countertops. They are also being increasingly used in general automotive applications. The most advanced examples perform routinely on spacecraft and aircraft in demanding environments. The earliest composite materials were made from straw and mud combined to form bricks for building construction . Ancient brick-making
1188-503: A group of U.S. Navy SEALs. The 38 were members of NATO and allied forces, including 22 Naval Special Warfare operators, five U.S. Army Aviation soldiers, three U.S. Air Force special operations personnel, and seven Afghan National Army commandos. A civilian translator and a U.S. military working dog were also killed in the crash. The crash was the single deadliest during the entire Operation Enduring Freedom campaign. The previous biggest single-day loss for American forces in Afghanistan involved
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#17328008264601296-1061: A high deformation setting and are often used in deployable systems where structural flexing is advantageous. Although high strain composites exhibit many similarities to shape-memory polymers, their performance is generally dependent on the fibre layout as opposed to the resin content of the matrix. Composites can also use metal fibres reinforcing other metals, as in metal matrix composites (MMC) or ceramic matrix composites (CMC), which includes bone ( hydroxyapatite reinforced with collagen fibres), cermet (ceramic and metal), and concrete . Ceramic matrix composites are built primarily for fracture toughness , not for strength. Another class of composite materials involve woven fabric composite consisting of longitudinal and transverse laced yarns. Woven fabric composites are flexible as they are in form of fabric. Organic matrix/ceramic aggregate composites include asphalt concrete , polymer concrete , mastic asphalt , mastic roller hybrid, dental composite , syntactic foam , and mother of pearl . Chobham armour
1404-591: A key operation of the war, Iranian Chinooks were landed behind Iraqi lines, deployed troops that silenced their artillery, and captured an Iraqi headquarters; the attack took the Iraqi forces by surprise. Despite the arms embargo in place upon Iran, it has managed to keep its Chinook fleet operational. Some of the Chinooks have been rebuilt by Panha . As of 2015, 20 to 45 Chinooks were operational in Iran. In 1976,
1512-709: A lightweight but thick core. The core material is normally low strength material, but its higher thickness provides the sandwich composite with high bending stiffness with overall low density . Wood is a naturally occurring composite comprising cellulose fibres in a lignin and hemicellulose matrix. Engineered wood includes a wide variety of different products such as wood fibre board, plywood , oriented strand board , wood plastic composite (recycled wood fibre in polyethylene matrix), Pykrete (sawdust in ice matrix), plastic-impregnated or laminated paper or textiles, Arborite , Formica (plastic) , and Micarta . Other engineered laminate composites, such as Mallite , use
1620-1064: A matrix of cement . Concrete is an inexpensive material, and will not compress or shatter even under quite a large compressive force. However, concrete cannot survive tensile loading (i.e., if stretched it will quickly break apart). Therefore, to give concrete the ability to resist being stretched, steel bars, which can resist high stretching (tensile) forces, are often added to concrete to form reinforced concrete . Fibre-reinforced polymers include carbon-fiber-reinforced polymers and glass-reinforced plastic . If classified by matrix then there are thermoplastic composites , short fibre thermoplastics , long fibre thermoplastics or long-fiber-reinforced thermoplastics . There are numerous thermoset composites, including paper composite panels . Many advanced thermoset polymer matrix systems usually incorporate aramid fibre and carbon fibre in an epoxy resin matrix. Shape-memory polymer composites are high-performance composites, formulated using fibre or fabric reinforcements and shape-memory polymer resin as
1728-699: A maximum gross weight of 33,000 lb (15,000 kg), with a maximum payload about 10,000 lb (4,500 kg) Delivery of the CH-47A Chinook to the U.S. Army began in August 1962. A total of 354 were built. The ACH-47A was known as the Armed/Armored CH-47A (or A/ACH-47A) before being designated ACH-47A as a U.S. Army Attack Cargo Helicopter, and unofficially referred to as Guns A Go-Go . Four CH-47A helicopters were converted to gunships by Boeing Vertol in late 1965. Three were assigned to
1836-464: A more substantially improved CH-47C. The CH-47B was powered by two Lycoming T55-L-7C 2,850 hp (2,130 kW) engines. It had a blunted rear rotor pylon, redesigned asymmetrical rotor blades, and strakes along the rear ramp and fuselage to improve flying characteristics. It could be equipped with two door-mounted M60D 7.62 mm NATO machine guns on the M24 armament subsystem and a ramp-mounted M60D using
1944-402: A mould to undergo a melding event. The part shape is fundamentally set after the melding event. However, under particular process conditions, it can deform. The melding event for a thermoset polymer matrix material is a curing reaction that is caused by the possibility of extra heat or chemical reactivity such as an organic peroxide. The melding event for a thermoplastic polymeric matrix material
2052-695: A new tandem-rotor helicopter, designated as the Vertol Model 107 or V-107. Around the same time, the United States Department of the Army announced its intention to replace the piston-engine –powered Sikorsky CH-37 Mojave with a new, gas turbine –powered helicopter. During June 1958, the U.S. Army ordered a small number of V-107s from Vertol under the YHC-1A designation; following testing, some Army officials considered it to be too heavy for
2160-802: A non-corrosive alternative to galvanized steel. In 2007, an all-composite military Humvee was introduced by TPI Composites Inc and Armor Holdings Inc, the first all-composite military vehicle . By using composites the vehicle is lighter, allowing higher payloads. In 2008, carbon fibre and DuPont Kevlar (five times stronger than steel) were combined with enhanced thermoset resins to make military transit cases by ECS Composites creating 30-percent lighter cases with high strength. Pipes and fittings for various purpose like transportation of potable water, fire-fighting, irrigation, seawater, desalinated water, chemical and industrial waste, and sewage are now manufactured in glass reinforced plastics. Composite materials used in tensile structures for facade application provides
2268-602: A number of lead plates were attached to the floor of each Chinook; even with such measures, pilots had to keep their distance from the reactors while also limiting flight times in the vicinity to a maximum of 45 minutes to avoid excessive radiation exposure. In April 2023, multiple Chinooks conducted the evacuation of the US Embassy in Khartoum, Sudan with Special Forces. (see also Sudanese civil war (2023–present) ) Chinooks have been deployed to Mali for MINUSMA . Since
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#17328008264602376-400: A redesigned cockpit to reduce workload, improved and redundant electrical systems and avionics, and the adoption of an advanced flight control system. It remains one of the few aircraft to be developed during the early 1960s – along with the fixed-wing Lockheed C-130 Hercules cargo aircraft – that has remained in both production and frontline service for over 60 years. The military version of
2484-467: A separate aviation medium helicopter company, the 147th, had arrived in Vietnam on 29 November 1965. This latter company was initially placed in direct support of the 1st Infantry Division . CH-47 crews quickly learned to mount an M60 machine gun in each of the forward doors. Sometimes they also installed an M2 machine gun to fire from the rear cargo door. The most spectacular mission in Vietnam for
2592-543: A single 40 mm M75 grenade launcher in the XM5/M5 armament subsystem (more commonly seen on the UH-1 series of helicopters). Rare newsreel footage shows one of the aircraft in action supporting the 8th Cavalry Regiment during an ambush at Bông Son, South Vietnam. The surviving aircraft, Easy Money , has been restored and is on display at Redstone Arsenal , Alabama. The CH-47B was an interim upgrade while Boeing worked on
2700-510: Is a tandem-rotor helicopter originally developed by American rotorcraft company Vertol and now manufactured by Boeing Defense, Space & Security . The Chinook is a heavy-lift helicopter that is among the heaviest lifting Western helicopters. Its name, Chinook, is from the Native American Chinook people of Oregon and Washington state. The Chinook was originally designed by Vertol, which had begun work in 1957 on
2808-413: Is a solidification from the melted state. The melding event for a metal matrix material such as titanium foil is a fusing at high pressure and a temperature near the melting point. It is suitable for many moulding methods to refer to one mould piece as a "lower" mould and another mould piece as an "upper" mould. Lower and upper does not refer to the mould's configuration in space, but the different faces of
2916-578: Is a special type of composite armour used in military applications. Additionally, thermoplastic composite materials can be formulated with specific metal powders resulting in materials with a density range from 2 g/cm to 11 g/cm (same density as lead). The most common name for this type of material is "high gravity compound" (HGC), although "lead replacement" is also used. These materials can be used in place of traditional materials such as aluminium, stainless steel, brass, bronze, copper, lead, and even tungsten in weighting, balancing (for example, modifying
3024-424: Is also crucial in the final design. Many of these finishes will involve rain-erosion coatings or polyurethane coatings. The mould and mould inserts are referred to as "tooling". The mould/tooling can be built from different materials. Tooling materials include aluminium , carbon fibre , invar , nickel , reinforced silicone rubber and steel. The tooling material selection is normally based on, but not limited to,
3132-469: Is also used in payload adapters, inter-stage structures and heat shields of launch vehicles . Furthermore, disk brake systems of airplanes and racing cars are using carbon/carbon material, and the composite material with carbon fibres and silicon carbide matrix has been introduced in luxury vehicles and sports cars . In 2006, a fibre-reinforced composite pool panel was introduced for in-ground swimming pools, residential as well as commercial, as
3240-441: Is another main factor. To support high capital investments for rapid and automated manufacturing technology, vast quantities can be used. Cheaper capital investments but higher labour and tooling expenses at a correspondingly slower rate assists the small production quantities. Many commercially produced composites use a polymer matrix material often called a resin solution. There are many different polymers available depending upon
3348-410: Is needed at least. The reinforcement receives support from the matrix as the matrix surrounds the reinforcement and maintains its relative positions. The properties of the matrix are improved as the reinforcements impart their exceptional physical and mechanical properties. The mechanical properties become unavailable from the individual constituent materials by synergism. At the same time, the designer of
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3456-415: Is no delamination at the fibre-matrix interface). This isostrain condition provides the upper bound for composite strength, and is determined by the rule of mixtures : where E C is the effective composite Young's modulus , and V i and E i are the volume fraction and Young's moduli, respectively, of the composite phases. For example, a composite material made up of α and β phases as shown in
3564-569: Is planning to buy sixty airframes to boost heavy lift capability. Spain had seventeen CH-47 which it is planning to upgrade CH-47F standard. By 2023, thirteen CH-47D were upgraded to CH-47F, and additionally, four new build CH-47F were acquired. There have been many versions of the Chinook over the decades, there are variants that involve major upgrades such as engines and avionics, ones for certain tasks, such as Special Operation missions, and finally there are version for certain countries, such as
3672-446: Is that they are able to have shape memory behaviour without needing any shape-memory polymers or shape-memory alloys e.g. balsa plies interleaved with hot glue, aluminium plies interleaved with acrylic polymers or PVC and carbon-fiber-reinforced polymer laminates interleaved with polystyrene . A sandwich-structured composite is a special class of composite material that is fabricated by attaching two thin but stiff skins to
3780-687: Is the CH-47F, which features several major upgrades to reduce maintenance, digitized flight controls, and is powered by two 4,733-horsepower (3,529 kW) Honeywell engines. An example of a British upgraded version is the HC.4; the first HC.4 first flew on 9 December 2010. A commercial model of the Chinook, the Boeing-Vertol Model 234, is used worldwide for logging, construction, fighting forest fires, and supporting petroleum extraction operations. In December 2006, Columbia Helicopters Inc purchased
3888-565: Is typically escorted by attack helicopters such as the AH-64 Apache for protection. Its lift capacity has been found of particular value in the mountainous terrain of Afghanistan, where high altitudes and temperatures limit the use of helicopters such as the UH-60 Black Hawk ; reportedly, one Chinook can replace up to five UH-60s in the air assault transport role. The Chinook helicopters of several nations have participated in
3996-618: The 2004 Asian tsunami , the Republic of Singapore Air Force assisted in the relief operations in neighboring Indonesia using its Chinooks; similarly, after the 2005 Kashmir earthquake , the Royal Air Force dispatched several Chinooks to Northern Pakistan to assist in recovery efforts. In August 1992, six CH-47Ds were deployed from Fort Bragg in North Carolina to provide relief in the wake of Hurricane Andrew in what
4104-587: The Argentine Army each deployed two CH-47C helicopters, which were widely used in general transport duties. Of the Army's aircraft, one was destroyed on the ground by 30 mm cannon fire from an RAF GR3 Harrier , while the other was captured by the British and reused after the war. Both Argentine Air Force helicopters returned to Argentina and remained in service until 2002. Three British Chinooks were destroyed on 25 May 1982 when Atlantic Conveyor
4212-584: The Canadian Forces ' surviving CH-147Cs and upgraded them to CH-47D. Six more new CH-47Ds were delivered in 1995 for a total of 13. The Dutch CH-47Ds are improved over U.S. Army CH-47Ds, including a long nose for Bendix weather radar, a " glass cockpit ", and improved T55-L-714 engines. As of 2011, the Netherlands planned upgrading 11 of them to the CH-47F standard at a later date. As of 2011, Singapore has 18 CH-47D/SDs, which includes twelve "Super D" Chinooks, in service. In 2008, Canada purchased 6 CH-47Ds from
4320-563: The F-14 Tomcat , as part of a modernization program. After an agreement signed between Boeing and Agusta , the Imperial Iranian Air Force purchased 20 Agusta-built CH-47Cs in 1971. The Imperial Iranian Army Aviation purchased 70 CH-47Cs from Agusta between 1972 and 1976. In late 1978, Iran placed an order for an additional 50 helicopters with Elicotteri Meridionali, but that order was canceled immediately after
4428-676: The Libyan Air Force purchased 24 Italian-built CH-47C helicopters, 14 of which were transferred to the Libyan Army during the 1990s. The Libyan Air Force recruited Western pilots and technicians to operate the CH-47 fleet. The Libyan Chinooks flew transport and support missions into Chad to supply Libyan ground forces operating there in the 1980s. Chinooks were occasionally used to transport Libyan special forces in assault missions in northern Chad. In 2002, Libya sold 16 helicopters to
H47 - Misplaced Pages Continue
4536-452: The coefficient of thermal expansion , expected number of cycles, end item tolerance, desired or expected surface condition, cure method, glass transition temperature of the material being moulded, moulding method, matrix, cost, and other various considerations. Usually, the composite's physical properties are not isotropic (independent of the direction of applied force) in nature. But they are typically anisotropic (different depending on
4644-505: The revolution ; 11 of them were delivered after multiple requests by Iran. In the 1978 Iranian Chinook shootdown , four Iranian CH-47Cs penetrated 15–20 km (9–12 mi) into Soviet airspace in the Turkmenistan Military District. They were intercepted by a MiG-23M which shot down one CH-47, killing eight crew members, and forced a second helicopter to land. Chinook helicopters were used in efforts by
4752-656: The type certificate of the Model 234 from Boeing. The Chinook has also been licensed to be built by companies outside the United States, such as Agusta (now AgustaWestland ) in Italy and Kawasaki in Japan. The Army finally settled on the larger Chinook as its standard medium-transport helicopter, and by February 1966, 161 aircraft had been delivered to the Army. The 1st Cavalry Division had brought its organic Chinook battalion (three Chinook companies) when it arrived in 1965 and
4860-472: The 53rd Aviation Detachment in South Vietnam for testing, with the remaining one retained in the U.S. for weapons testing. By 1966, the 53rd was redesignated the 1st Aviation Detachment (Provisional) and attached to the 228th Assault Support Helicopter Battalion of the 1st Cavalry Division (Airmobile). By 1968, only one gunship remained, and transport demands prevented more conversions. It was returned to
4968-559: The Afghanistan War, including aircraft from Britain, Italy, the Netherlands, Spain, Canada, and Australia. Despite the age of the Chinook, it is still in heavy demand, in part due its proven versatility and ability to operate in demanding environments such as Afghanistan. In May 2011, an Australian Army CH-47D crashed during a resupply mission in Zabul Province, resulting in one fatality and five survivors. The helicopter
5076-702: The Army procure the Vertol -built medium transport helicopter. However, funding for full-scale development was not then available, and the Army vacillated on its design requirements. Some officials in Army Aviation thought that the new helicopter should be operated as a light tactical transport aimed at taking over the missions of the old piston-engined Piasecki H-21 and Sikorsky H-34 helicopters, and be consequently capable of carrying about 15 troops (one squad ). Another faction in Army Aviation thought that
5184-561: The CH-47F would replace its older Chinooks, which had been in service since 1994, enabling the Republic of Singapore Air Force to meet its requirements for various operations, including Search and Rescue (SAR), Aeromedical Evacuation (AME), and Humanitarian Assistance and Disaster Relief (HADR) operations. The German government announced in June 2022 that the CH-47F Block 2 was selected as the winner of its heavy helicopter program to replace its Sikorsky CH-53G Sea Stallion fleet. Germany
5292-571: The Chinook fleet was used for casualty evacuation, and due to the very heavy demand for the helicopters, they were usually overburdened with wounded. Perhaps the most cost effective use of the Chinook was the recovery of other downed aircraft. At the war's peak the US Army had 21 Chinook companies in Vietnam. Pilots discovered the CH-47A's transmission system could not handle the two gas turbines running at full power, and high humidity and heat reduced
5400-431: The Chinook presented a major problem of "customer education". Commanders and crew chiefs had to be constantly alert that eager soldiers did not overload the temptingly large cargo compartment. It would be some time before troops would be experts at using sling loads. The Chinook soon proved to be such an invaluable aircraft for artillery movement and heavy logistics that it was seldom used as an assault troop carrier. Some of
5508-446: The Chinook was the placing of artillery batteries in perilous mountain positions inaccessible by any other means, and then keeping them resupplied with large quantities of ammunition. The 1st Cavalry Division found that its CH-47s were limited to a 7,000-pound (3,200 kg) payload when operating in the mountains, but could carry an additional 1,000 pounds (450 kg) when operating near the coast. As with any new piece of equipment,
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#17328008264605616-515: The HC-1B was redesignated CH-47A under the 1962 United States Tri-Service aircraft designation system . The Chinook possesses several means of loading various cargoes, including multiple doors across the fuselage, a wide loading ramp located at the rear of the fuselage and a total of three external ventral cargo hooks to carry underslung loads. Capable of a top speed of 170 knots (200 mph; 310 km/h), upon its introduction to service in 1962,
5724-461: The Huey and the Army's tacticians' insistence that initial air assaults be built around the squad. The Army pushed for both the Huey and the Chinook, and this focus was responsible for the acceleration of its air mobility effort. Improved and more powerful versions of the CH-47 have been developed since the helicopter entered service. Often the same airframe was upgraded to later standards, or sometimes
5832-573: The Iranian against Kurdish rebels in 1979. During the Iran–Iraq War , Iran made heavy use of its US-bought equipment, and lost at least eight CH-47s during the 1980–1988 period, most notably during a clash on 15 July 1983, when an Iraqi Mirage F1 destroyed three Iranian Chinooks transporting troops to the front line, and on 25–26 February 1984, when Iraqi MiG-21 fighters shot down two examples. On 22 March 1982, in Operation Fath ol-Mobin ,
5940-495: The J model built by and for Japan. The pre-1962 designation for Model 114 development aircraft that would be redesignated CH-47 Chinook. The all-weather, medium-lift CH-47A Chinook was powered initially by Lycoming T55 -L-5 engines rated at 2,200 horsepower (1,640 kW), which were replaced by the T55-L-7 rated at 2,650 hp (1,980 kW) engines or T55-L-7C engines rated at 2,850 hp (2,130 kW). The CH-47A had
6048-538: The M41 armament subsystem. Some CH-47 "bombers" were equipped to drop tear gas or napalm from the rear cargo ramp onto Viet Cong bunkers. The CH-47B could be equipped with a hoist and cargo hook. The Chinook proved especially valuable in "Pipe Smoke" aircraft recovery missions. The "Hook" recovered about 12,000 aircraft valued at over $ 3.6 billion during the war; 108 were built. The CH-47C featured more powerful engines and transmissions. Three sub-versions were built,
6156-714: The MH-47D, but with increased fuel capacity similar to the CH-47SD and terrain following/terrain avoidance radar. In 1995, the Royal Air Force ordered eight Chinook HC3s , effectively a lower cost MH-47E for special operations. They were delivered in 2001, but never became operational due to technical issues with their avionics fit, unique to the HC3. In 2008, work started to revert the HC3s to HC2 standard, to enable them to enter service. As of 2017 they were upgraded to HC5 standard with
6264-560: The U.S. for the Canadian Helicopter Force Afghanistan for $ 252 million. With 1 CH-47D lost to an accident, the remaining five were sold in 2011 after the end of Canada's Afghanistan mission and replaced with seven CH-147Fs. The U.S. Army is surplusing many of its CH-47Ds for use in FAA restricted category. The MH-47D was developed for special forces operations and has inflight refueling capability,
6372-711: The United Arab Emirates, as due to the Western embargo and lack of funds, maintaining them was difficult. The sale to UAE was a $ 939 million package that included equipment, parts, and training. The number of CH-47s still in existence or operational during the ongoing Libyan civil wars that started in 2011 is not known. The Chinook was used both by Argentina and the United Kingdom during the Falklands War in 1982. The Argentine Air Force and
6480-606: The United States Department of the Army announced its intention to replace the Sikorsky CH-37 Mojave , which was powered by piston engines , with a new, gas turbine-powered helicopter. Turbine engines were also a key design feature of the smaller UH-1 "Huey" utility helicopter. Following a design competition, in September 1958, a joint Army–Air Force source selection board recommended that
6588-517: The United States, and the program stopped. The ACH-47A carried five 7.62 × 51 mm M60D machine guns or .50-caliber (12.7 mm) M2HB heavy machine guns , provided by the XM32 and XM33 armament subsystems, two 20 mm M24A1 cannons , two 19-tube 2.75-inch (70 mm) Folding Fin Aerial Rocket launchers (XM159B/XM159) or sometimes two M18/M18A1 7.62 × 51 mm gun pods , and
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#17328008264606696-667: The advantage of being translucent. The woven base cloth combined with the appropriate coating allows better light transmission. This provides a very comfortable level of illumination compared to the full brightness of outside. The wings of wind turbines, in growing sizes in the order of 50 m length are fabricated in composites since several years. Two-lower-leg-amputees run on carbon-composite spring-like artificial feet as quick as non-amputee athletes. High-pressure gas cylinders typically about 7–9 litre volume x 300 bar pressure for firemen are nowadays constructed from carbon composite. Type-4-cylinders include metal only as boss that carries
6804-459: The airframes were built to the newer upgrade. The U.S. Army's first major design leap was the now-common CH-47D, which entered service in 1982. Improvements from the CH-47C included upgraded engines, composite rotor blades, a redesigned cockpit to reduce pilot workload, improved and redundant electrical systems, an advanced flight control system, and improved avionics. The latest mainstream generation
6912-697: The assault missions and too light for transport purposes. While the YHC-1A would be improved and adopted by the U.S. Marine Corps as the CH-46 Sea Knight , the Army sought a heavier transport helicopter, and ordered an enlarged derivative of the V-107 with the Vertol designation Model 114. Initially designated as the YCH-1B , on 21 September 1961, the preproduction rotorcraft performed its maiden flight . In 1962,
7020-405: The cargo lifting and dropping. While hovering over a specific location, a twin-rotor helicopter has increased stability over a single rotor when weight is added or removed, for example, when troops drop from or begin climbing up ropes to the aircraft, or when other cargo is dropped. If one engine fails, the other can drive both rotors. The "sizing" of the Chinook was directly related to the growth of
7128-428: The case of spider silk, the properties of the material can even be dependent on the size of the crystals, independent of the volume fraction. Ironically, single component polymeric materials are some of the most easily tunable composite materials known. Normally, the fabrication of composite includes wetting, mixing or saturating the reinforcement with the matrix. The matrix is then induced to bind together (with heat or
7236-644: The centre of gravity of a tennis racquet ), vibration damping, and radiation shielding applications. High density composites are an economically viable option when certain materials are deemed hazardous and are banned (such as lead) or when secondary operations costs (such as machining, finishing, or coating) are a factor. There have been several studies indicating that interleaving stiff and brittle epoxy-based carbon-fiber-reinforced polymer laminates with flexible thermoplastic laminates can help to make highly toughened composites that show improved impact resistance. Another interesting aspect of such interleaved composites
7344-941: The coating increases the surface hydrophobicity, hardness and wear resistance. Ferromagnetic composites, including those with a polymer matrix consisting, for example, of nanocrystalline filler of Fe-based powders and polymers matrix. Amorphous and nanocrystalline powders obtained, for example, from metallic glasses can be used. Their use makes it possible to obtain ferromagnetic nanocomposites with controlled magnetic properties. Fibre-reinforced composite materials have gained popularity (despite their generally high cost) in high-performance products that need to be lightweight, yet strong enough to take harsh loading conditions such as aerospace components ( tails , wings , fuselages , propellers ), boat and scull hulls, bicycle frames, and racing car bodies. Other uses include fishing rods , storage tanks , swimming pool panels, and baseball bats . The Boeing 787 and Airbus A350 structures including
7452-470: The designation of HC-1B. On 21 September 1961, the preproduction Boeing Vertol YCH-1B made its initial hovering flight. During 1962, the HC-1B was redesignated the CH-47A under the 1962 United States Tri-Service aircraft designation system ; it was also named "Chinook" after the Chinook people of the Pacific Northwest. The CH-47 is powered by two turboshaft engines, mounted on each side of
7560-577: The development of its Reusable Launch Vehicle Technology Demonstration Program , with Chinook helicopters air-dropping two test vehicles during the RLV-LEX-01 and RLV-LEX-02 conducted on April 2, 2023, and March 22, 2024, respectively. In February 2007, the Royal Netherlands Air Force became the first international customer of the CH-47F model, expanding their Chinook fleet to seventeen. On 10 August 2009, Canada signed
7668-410: The direction of the applied force or load). For instance, the composite panel's stiffness will usually depend upon the orientation of the applied forces and/or moments. The composite's strength is bounded by two loading conditions, as shown in the plot to the right. If both the fibres and matrix are aligned parallel to the loading direction, the deformation of both phases will be the same (assuming there
7776-470: The figure to the right under isostrain, the Young's modulus would be as follows: E C = V α E α + V β E β {\displaystyle E_{C}=V_{\alpha }E_{\alpha }+V_{\beta }E_{\beta }} where V α and V β are the respective volume fractions of each phase. This can be derived by considering that in
7884-514: The final product, or the fibre content is increased. As a rule of thumb, lay up results in a product containing 60% resin and 40% fibre, whereas vacuum infusion gives a final product with 40% resin and 60% fibre content. The strength of the product is greatly dependent on this ratio. Martin Hubbe and Lucian A Lucia consider wood to be a natural composite of cellulose fibres in a matrix of lignin . Several layup designs of composite also involve
7992-413: The first with Lycoming T55-L-7C engines delivering 2,850 shp (2,130 kW). The "Super C" had Lycoming T55-L-11 engines delivering 3,750 shp (2,800 kW), an upgraded maximum gross weight of 46,000 lb (21,000 kg), and pitch stability augmentation. The T55-L-11 engines were less reliable, as they had been hurriedly introduced to increase payload; thus, they were temporarily replaced by
8100-536: The gunners from firing into the rotor blades. Dust filters were also added to improve engine reliability. Of the nearly 750 Chinook helicopters in the U.S. and South Vietnam fleets, about 200 were lost in combat or wartime operational accidents. The U.S. Army CH-47s supported the 1st Australian Task Force as required. Four CH-47s were converted into ACH-47As by adding armor and improved engines. Its armament included two fixed forward firing M24A1 20 mm cannons , one turret with 40 mm automatic grenade launcher on
8208-508: The helicopter has been exported to nations across the world; the U.S. Army and the Royal Air Force (see Boeing Chinook (UK variants) ) have been its two largest users. The civilian version of the Chinook is the Boeing Vertol 234. It has been used by civil operators not only for passenger and cargo transport, but also for aerial firefighting and to support logging , construction , and oil extraction industries. During late 1956,
8316-572: The helicopter was considerably faster than contemporary 1960s utility helicopters and attack helicopters , and is still one of the fastest helicopters in the US inventory. Improved and more powerful versions of the Chinook have also been developed since its introduction; one of the most substantial variants to be produced was the CH-47D, which first entered service in 1982; improvements from the CH-47C standard included upgraded engines, composite rotor blades,
8424-422: The helicopter's rear pylon and connected to the rotors by drive shafts. Initial models were fitted with Lycoming T55 engines rated at 2,200 hp (1,600 kW) each. The counter-rotating rotors eliminate the need for an antitorque vertical rotor, allowing all power to be used for lift and thrust. The ability to adjust lift in either rotor makes it less sensitive to changes in the center of gravity, important for
8532-414: The individual phases are given by Hooke's Law, σ β = E β ϵ {\displaystyle \sigma _{\beta }=E_{\beta }\epsilon } σ α = E α ϵ {\displaystyle \sigma _{\alpha }=E_{\alpha }\epsilon } Combining these equations gives that the overall stress in
8640-651: The isostrain case, ϵ C = ϵ α = ϵ β = ϵ {\displaystyle \epsilon _{C}=\epsilon _{\alpha }=\epsilon _{\beta }=\epsilon } Assuming that the composite has a uniform cross section, the stress on the composite is a weighted average between the two phases, σ C = σ α V α + σ β V β {\displaystyle \sigma _{C}=\sigma _{\alpha }V_{\alpha }+\sigma _{\beta }V_{\beta }} The stresses in
8748-764: The less stiff, amorphous phase. Polymeric materials can range from 0% to 100% crystallinity aka volume fraction depending on molecular structure and thermal history. Different processing techniques can be employed to vary the percent crystallinity in these materials and thus the mechanical properties of these materials as described in the physical properties section. This effect is seen in a variety of places from industrial plastics like polyethylene shopping bags to spiders which can produce silks with different mechanical properties. In many cases these materials act like particle composites with randomly dispersed crystals known as spherulites. However they can also be engineered to be anisotropic and act more like fiber reinforced composites. In
8856-406: The matrix nature, such as solidification from the melted state for a thermoplastic polymer matrix composite or chemical polymerization for a thermoset polymer matrix . According to the requirements of end-item design, various methods of moulding can be used. The natures of the chosen matrix and reinforcement are the key factors influencing the methodology. The gross quantity of material to be made
8964-625: The matrix. Since a shape-memory polymer resin is used as the matrix, these composites have the ability to be easily manipulated into various configurations when they are heated above their activation temperatures and will exhibit high strength and stiffness at lower temperatures. They can also be reheated and reshaped repeatedly without losing their material properties. These composites are ideal for applications such as lightweight, rigid, deployable structures; rapid manufacturing; and dynamic reinforcement. High strain composites are another type of high-performance composites that are designed to perform in
9072-464: The maximum lift by more than 20% in the low lands and 30% in mountain areas. More powerful, improved transmission and strengthened fuselages arrived in 1968 with the CH-47B, followed a few months later by the CH-47C. The CH-47s in Vietnam were generally armed with a single 0.308 in ( 7.62 mm ) M60 machine gun on a pintle mount on either side of the aircraft for self-defense, with stops fitted to keep
9180-510: The more reliable Lycoming T55-L-7C. The Super C was distinguishable from the standard "C" by the uprated maximum gross weight. The type was not approved by the FAA for civil aviation due to the nonredundant hydraulic flight boost system drive. The hydraulic system was redesigned for the succeeding CH-47D, allowing it to achieve certification as the Boeing Model 234. A total of 233 CH-47Cs were built. Canada bought eight CH-47Cs; deliveries of
9288-420: The moulded panel. There is always a lower mould, and sometimes an upper mould in this convention. Part construction commences by applying materials to the lower mould. Lower mould and upper mould are more generalized descriptors than more common and specific terms such as male side, female side, a-side, b-side, tool side, bowl, hat, mandrel, etc. Continuous manufacturing utilizes a different nomenclature. Usually,
9396-451: The moulded product is referred to as a panel. It can be referred to as casting for certain geometries and material combinations. It can be referred to as a profile for certain continuous processes. Some of the processes are autoclave moulding , vacuum bag moulding , pressure bag moulding , resin transfer moulding , and light resin transfer moulding . Other types of fabrication include casting , centrifugal casting, braiding (onto
9504-401: The new helicopter should be much larger, enabling it to airlift large artillery pieces and possess enough internal space to carry the new MGM-31 "Pershing" missile system . During 1957, Vertol commenced work upon a new tandem-rotor helicopter, designated as the Vertol Model 107 or V-107. During June 1958, the U.S. Army awarded a contract to Vertol for the acquisition of a small number of
9612-442: The nose, five .50 in machine guns and two weapon pods on the sides that could carry either XM159B/XM159C 70 mm rocket launchers or 7.62 mm miniguns. They arrived in Vietnam in 1966, and they engaged in six months of operational testing at An Khê Army Airfield . They performed well in combat, but its high maintenance costs and demand for use in troop and cargo transport was stronger. Three ACH-47s were lost. One collided with
9720-441: The principal mover of the 155 mm M198 howitzer , plus 30 rounds of ammunition, and an 11-man crew. The CH-47D has advanced avionics, including Global Positioning System . Nearly all US Army CH-47Ds were converted from previous A, B, and C models, a total of 472 being converted. The last U.S. Army CH-47D built was delivered to the U.S. Army Reserve , located at Fort Hood, Texas , in 2002. The Netherlands acquired all seven of
9828-477: The product or structure receives options to choose an optimum combination from the variety of matrix and strengthening materials. To shape the engineered composites, it must be formed. The reinforcement is placed onto the mould surface or into the mould cavity. Before or after this, the matrix can be introduced to the reinforcement. The matrix undergoes a melding event which sets the part shape necessarily. This melding event can happen in several ways, depending upon
9936-404: The rotorcraft, giving it the YHC-1A designation. As ordered, the YHC-1A possessed the capacity to carry a maximum of 20 troops. Three underwent testing by the Army for deriving engineering and operational data. However, the YHC-1A was considered by many figures within the Army users to be too heavy for the assault role, while too light for the more general transport role. Accordingly, a decision
10044-429: The same airframe as earlier models, with more powerful engines. Early CH-47Ds were powered by two T55-L-712 engines. The most common engine is the later T55-GA-714A. With its triple-hook cargo system, the CH-47D can carry heavy payloads internally and up to 26,000 lb (12,000 kg) (such as 40-foot or 12-meter containers) externally. It was introduced into service in 1979. In air assault operations, it often serves as
10152-540: The same title formed as a letter–number combination. If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=H47&oldid=1085753754 " Category : Letter–number combination disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Boeing-Vertol H-47 Chinook The Boeing CH-47 Chinook
10260-404: The starting raw ingredients. There are several broad categories, each with numerous variations. The most common are known as polyester , vinyl ester , epoxy , phenolic , polyimide , polyamide , polypropylene , PEEK , and others. The reinforcement materials are often fibres but also commonly ground minerals. The various methods described below have been developed to reduce the resin content of
10368-616: The subsequent Operation Desert Storm in 1990–91. The CH-47D has seen wide use in Operation Enduring Freedom in Afghanistan and Operation Iraqi Freedom in Iraq. The Chinook is being used in air assault missions, inserting troops into fire bases , and later bringing food, water, and ammunition. It is also the casualty evacuation aircraft of choice in the British Armed Forces . In combat theaters , it
10476-447: The summary of the state-of-the-art techniques for fabrication of the 3D structure of graphene, and the examples of the use of these foam like structures as a core for their respective polymer composites. Although the two phases are chemically equivalent, semi-crystalline polymers can be described both quantitatively and qualitatively as composite materials. The crystalline portion has a higher elastic modulus and provides reinforcement for
10584-477: The thread to screw in the valve. On 5 September 2019, HMD Global unveiled the Nokia 6.2 and Nokia 7.2 which are claimed to be using polymer composite for the frames. Composite materials are created from individual materials. These individual materials are known as constituent materials, and there are two main categories of it. One is the matrix ( binder ) and the other reinforcement . A portion of each kind
10692-413: The two dozen distribution centers and trucks, proving essential as trucks could not reach the worst hit areas due to downed trees and power lines. They flew everyday for approximately three weeks, moving supplies and personnel around the disaster zone as well as carrying media and government officials, including then Congressman Bill Nelson . Ultimately, the Chinooks supplied 64 distribution sites throughout
10800-476: The type began in 1974. Receiving the Canadian designation "CH-147", these were fitted with a power hoist above the crew door; other changes included a flight engineer station in the rear cabin: operators referred to the configuration as the "Super C". The CH-47C was used widely during the Vietnam War, eventually replacing the older Piasecki H-21 Shawnee in the combat assault support role. The CH-47D shares
10908-624: The type's inception, the Chinook has carried out various secondary missions, including medical evacuation, disaster relief, search and rescue, aircraft recovery, fire fighting, and heavy construction assistance. In February 2020, the Indian Air Force started using Chinooks at theatres such as Ladakh and Siachen Glacier to assist Indian forces deployed at the Indian borders with China and Pakistan . The Indian Space Research Organisation has also enlisted Indian Air Force Chinooks during
11016-414: The wings and fuselage are composed largely of composites. Composite materials are also becoming more common in the realm of orthopedic surgery , and it is the most common hockey stick material. Carbon composite is a key material in today's launch vehicles and heat shields for the re-entry phase of spacecraft . It is widely used in solar panel substrates, antenna reflectors and yokes of spacecraft. It
11124-473: The zone and transported 1.2 million pounds of supplies before the urgent relief phase ended. Three of Japan's CH-47s were used to cool Reactors 3 and 4 of the Fukushima Nuclear power plant following the 9.0 earthquake in 2011 ; they were used to collect sea water from the nearby ocean and drop it over the affected areas. In order to protect the crew from the heightened radiation levels present,
11232-442: Was documented by Egyptian tomb paintings . Wattle and daub is one of the oldest composite materials, at over 6000 years old. Concrete is also a composite material, and is used more than any other synthetic material in the world. As of 2009 , about 7.5 billion cubic metres of concrete are made each year Concrete is the most common artificial composite material of all and typically consists of loose stones (aggregate) held with
11340-455: Was made to procure a heavier transport helicopter, and at the same time, upgrade the UH-1 "Huey" to serve as the needed tactical troop transport. The YHC-1A would be improved and adopted by the Marines as the CH-46 Sea Knight in 1962. As a result, the Army issued a new order to Vertol for an enlarged derivative of the V-107, known by internal company designation as the Model 114, which it gave
11448-750: Was one of the first major helicopter disaster relief operations on US soil. Then President George H. W. Bush ordered the military to assist. The Chinooks arrived at Miami-Opa Locka Executive Airport , just outside of the disaster zone, one day after the President's order; early on, they performed a wide loop over Homestead and Florida City to publicly display their presence, helping to curtail lawlessness and looting. The Chinooks initially flew twelve sorties per day out of Opa Locka, which expanded over time, often supporting distribution operations at Homestead AFB and Opa Locka, as well as delivering relief payloads via internal storage, not using sling loads, supplementing
11556-489: Was struck by an Exocet sea-skimming missile fired by an Argentine Super Étendard . The sole surviving British Chinook, Bravo November , did outstanding service in the Falklands, lifting 81 troops on one occasion. Since April 2022, it has been on display at Royal Air Force Museum Cosford . About 163 CH-47Ds of various operators were deployed to Saudi Arabia , Kuwait , and Iraq during Operation Desert Shield and
11664-572: Was unable to be recovered and was destroyed in place. To compensate for the loss, the ADF added two ex-U.S. Army CH-47Ds to the fleet which are expected to be in service until the introduction of the CH-47Fs in 2016. On 6 August 2011, a Chinook crashed near Kabul, killing all of the 38 aboard. The Chinook was reportedly shot down with a rocket-propelled grenade by the Taliban while attempting to assist
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