Saturday 8 December 2012

3 Best Heavy Transport Chopper In The World


The CH-53 Sea Stallion is the most common name for the Sikorsky S-65 family of heavy-lift transport helicopters. Originally developed for use by the United States Marine Corps, it is also in service with Germany, Iran, Israel, and Mexico. The United States Air Force operated the HH-53 "Super Jolly Green Giant" during the late- and post-Vietnam War era, updating most of them as the MH-53 Pave Low. The dimensionally-similar CH-53E Super Stallion is a heavier-lifting, improved version designated S-80E by Sikorsky. Its third engine makes it more powerful than the Sea Stallion, which it has replaced in the heavy-lift mission.The Sea Stallion has a fuselage design similar to the Sikorsky S-61R/Jolly Green Giant series. It has a passenger door on the right side of the fuselage behind the cockpit and a power-operated rear loading ramp. The fuselage was watertight, though not intended for amphibious use, and only landed on water in emergencies. The Stallion has mechanical flight controls which are backed by three independent hydraulic systems. Armor protects crew and vital systems. The CH-53A carries a crew of four; pilot, copilot, crew chief, and an aerial observer, a load of 38 troops, 24 litters with medical attendants, an internal cargo load of 8,000 pounds (3,600 kg) or an external load of 13,000 pounds (5,900 kg) on the single-point sling hook. The CH-53A is equipped with a pair of 7.62 mm M60 machine guns that point out to each side of the fuselage. The CH-53D features uprated engines, initially T64-GE-412 with 3,695 shp (2,755 kW) then the T64-413 with 3,925 shp (2,927 kW) with an uprated transmission. Its interior added seats to allow for 55 troops. CH-53Ds are generally armed with twin .50 BMG (12.7 mm) M2/XM218 machine guns. In later years, CH-53Ds have been fitted with defensive countermeasures including an AN/ALE-39 chaff dispenser and an AN/ALQ-157 infrared countermeasure. The CH-53A features a six-bladed main rotor and four-bladed tail rotor developed from those used on the S-64 Skycrane. To save space on board naval vessels, the tail boom and the rotors folded. Initially, the CH-53 was powered by twin General Electric T64-6 turboshaft engines providing 2,850 shaft horsepower (2,130 kW) each, each engine being located on the upper fuselage. Later engines included the T64-1 with 3,080 shp (2,300 kW) and the T64-16 with 3,485 shp (2,599 kW). The HH-53B featured T64-3 engines producing 3,080 shp (2,300 kW).
Later production CH-53Ds featured a Blade Inspection Method (BIM) scheme to detect cracks in its metal rotors. BIM involved pressurizing the interior of the rotor blades with nitrogen. If a crack is present pressure is lost and a red indicator on the rotor blade tip was tripped. Later, the BIM system was connected to a cockpit display. BIM reduced the need to swap out rotor blades on a routine basis.



The British Boeing Chinook is a tandem rotor helicopter operated by the Royal Air Force. A series of variants based on the United States Army's Boeing CH-47 Chinook, the RAF Chinook fleet is the largest outside the United States. RAF Chinooks have seen extensive service including fighting in the Falklands War, peace-keeping commitments in the Balkans, and action in the Iraq and Afghanistan wars. The Chinook HC2 aircraft, normally based at RAF Odiham, provides heavy-lift support and transport across all branches of the British armed forces, and is supported by the smaller, medium-lift helicopters such as the AgustaWestland Merlin HC3 and the Westland Puma HC1, based at RAF Benson and RAF Aldergrove. 
In March 1967 an order was placed for fifteen Chinook HC1s, standing for Helicopter, Cargo Mark 1, for the Royal Air Force to replace the Bristol Belvedere. This original HC1 variant was to be based on the CH-47B but the order was cancelled in a review of defence spending in November 1967, UK Chinook procurement ambitions were revived in 1978 with an announced requirement for a new heavy-lift helicopter to replace the Westland Wessex. Thirty Chinooks were ordered at a price of US$200 million. These helicopters, comparable to the CH-47C with Lycoming T55-L-11E engines, were again designated Chinook HC1, and entered service in December 1980. Eight more HC1s were delivered from 1984 to 1986 with the CH-47D's Lycoming T55-L-712 turboshafts. The replacement of the HC1's metal rotor blades with aluminium and glass fibre composite rotor blades saw these aircraft designated Chinook HC1B. All surviving aircraft were later returned to Boeing and updated to the Chinook HC2 standard for further service within the RAF. The US Army's next generation Chinook, the CH-47D, entered service in 1982. Improvements from the CH-47C included upgraded engines, composite rotor blades, a redesigned cockpit to reduce pilot workload, redundant and improved electrical systems, an advanced flight control system (FCS) and improved avionics. The RAF returned their original HC1s to Boeing for upgrading to CH-47D standard, the first of which returned to the UK in 1993.
Three additional HC2 Chinooks were ordered with delivery beginning in 1995. Another six were ordered in 1995 under the Chinook HC2A designation;[11] the main difference between these and the standard HC2 was the strengthening of the front fuselage to allow the fitting of an aerial refueling probe in future. One Argentine CH-47C was captured during the Falklands War, and used by the RAF as a training aid. The rear fuselage was later used to repair a crashed RAF Chinook in 2003. In 2006, the retirement dates for the HC2 and HC2A fleets were scheduled for 2015 and 2025 respectively, but if planned upgrades are made both types could expect to be flying until 2040.



The American Boeing CH-47 Chinook is an American twin-engine, tandem rotor heavy-lift helicopter. With a top speed of 170 knots (196 mph, 315 km/h) it is faster than contemporary utility and attack helicopters of the 1960s. The CH-47 is one of the few aircraft of that era – along with the fixed-wing Lockheed C-130 Hercules cargo aircraft – that is still in production and front line service, with over 1,179 built to date. Its primary roles include troop movement, artillery emplacement and battlefield resupply. It has a wide loading ramp at the rear of the fuselage and three external-cargo hooks. The Chinook was designed and initially produced by Boeing Vertol in the early 1960s. The helicopter is now produced by Boeing Rotorcraft Systems. Chinooks have been sold to 16 nations with the US Army and the Royal Air Force (see Boeing Chinook (UK variants)) being the largest users. The CH-47 is among the heaviest lifting Western helicopters. Improved and more powerful versions of the CH-47 have been developed since the helicopter entered service. The US 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 is the CH-47F, which features several major upgrades to reduce maintenance, digitized flight controls, and is powered by two 4,733-horsepower Honeywell engines. 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. On 15 December 2006, the Columbia Helicopters company of the Salem, Oregon, metropolitan area, purchased the Type Certificate of the Model 234 from Boeing. The Chinook has also been licensed to be built by companies outside of the United States, such as Elicotteri Meridionali (now AgustaWestland) in Italy, Kawasaki in Japan.



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