[CH-47A


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) but then 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 a maximum gross weight of 33,000 pounds (15,000 kg). Initial delivery of the CH-47A Chinook to the US Army was in August 1962. A total of 349 were built.

[ ACH-47A


The ACH-47A was originally known as the Armed/Armored CH-47A (or A/ACH-47A). It was officially designated ACH-47A by US Army—Attack Cargo Helicopter—and unofficially "Guns A Go-Go"). Four CH-47A helicopters were converted to gunships by Boeing Vertol in late 1965. Three were assigned to 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 logistical concerns prevented more conversions. It was returned to the United States, and the program stopped.
The ACH-47A carried five M60D 7.62x51 mm machine guns or M2HB .50 caliber machine guns, provided by the XM32 and XM33 armament subsystems, two M24A1 20 mm cannons, two XM159B/XM159C 19-Tube 2.75" rocket launchers or sometimes two M18/M18A1 7.62x51 mm gun pods, and a single M75 40 mm grenade launcher in the XM5/M5 armament subsystem (more commonly seen on the UH-1 series of helicopters). The surviving aircraft, Easy Money, has been restored and is on display at Redstone Arsenal, Alabama.[3][4][5]

[ CH-47B


The CH-47B was an interim solution while Boeing worked on a more substantially improved CH-47C. CH-47B was powered by two Lycoming T55-L-7C 2,850 shp (2,130 kW) engines. It featured 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 the M41 armament subsystem. Some CH-47 "bombers" were equipped to drop tear gas or napalm from the rear cargo ramp onto NLF (aka Việt Cộng) bunkers. The CH-47 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 built.

[ CH-47C


The CH-47C featured more powerful engines and transmissions.^[11] Three versions of the "C model" were built. The first had Lycoming T55-L-7C engines delivering 2,850 shp (2,130 kW). The "Super C" included 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 a pitch stability augmentation system (PSAS). Due to difficulties with the T55-L-11 engines, which were hurriedly brought to war to increase payload, they were temporarily removed from the "Super C" prior to 1970 and the very reliable Lycoming T55-L-7C's were installed until the L-11 engine difficulties could be quantified and corrected. This L-7C engine configuration was affectionately referred to as the "baby C" although it was still a Super C. It distinguished itself from the "C" in that it had PSAS and an uprated maximum gross weight. The CH-47 A, B, and all variants of the C were not able to receive certification from the FAA for civil use due to the non-redundant hydraulic flight boost system drive. A redesign of the hydraulic boost system drive was incorporated in the CH-47D which allowed that model to achieve FAA certification as the Boeing Model 234. 233 CH-47Cs were built.
The CH-47A, B, and all versions of the C saw wide use during the Vietnam war. They replaced the H-21 Shawnee in the combat assault support role.
The Royal Air Force variant of the CH-47C is known as the Chinook HC1.
The export version of the CH-47C Chinook for the Italian Army was designated "CH-47C Plus".

[ CH-47D

Spanish Army in 2009



The CH-47D was originally powered by two T55-L-712 engines, but most are now fitted with the T55-GA-714A. Models CH-47A, CH-47B, and CH-47C, all used the same airframe, but later models featured upgraded engines. With its triple-hook cargo system, the CH-47D can carry heavy payloads internally and up to 26,000 pounds - for example, bulldozers and 40-foot (12 m) containers - externally, at speeds over 155 mph (250 km/h). In air assault operations, it often serves as the principal mover of the 155 mm M198 howitzer, 30 rounds of ammunition, and an 11-man crew. Like most US Army helicopters, the Chinook has advanced avionics and electronics, including the Global Positioning System.
Nearly all of the Army production CH-47D models were conversions from previous US Army A, B, and C models. The last US Army D model built was delivered to the U.S. Army Reserve, located at Fort Hood, Texas, in early 2002.^[12]
The Royal Air Force versions of the CH-47D are known as the Chinook HC2 and HC2A. The CH-47SD is a modified variant of the CH-47D, with extended range fuel tanks and higher payload capacities. It is in use by the Republic of Singapore Air Force, Greek Army and the Republic of China. The CH-47DG is an upgraded version of the CH-47C for the Greek Army. The CH-47D is an upgraded version of the CH-47LR for the Republic of Korea Army.

[ MH-47D

]
A U.S. MH-47D stands ready to receive medical supplies in Feyzabad, Afghanistan.



The MH-47D variant was developed for special forces operations and has in-flight refueling capability, a fast-rope rappelling system and other upgrades. The MH-47D was used by US Army 160th Special Operations Aviation Regiment. 12 MH-47D helicopters were produced. 6 were conversions from CH-47A models and 6 were conversions from CH-47C models.^[13]

[ MH-47E


The current model used by US Army Special Operations is the MH-47E. Beginning with the E model prototype manufactured in 1991, there were a total of 26 Special Operations Aircraft produced. All aircraft were assigned to 2-160th SOAR(A)"Nightstalkers", home based at Fort Campbell Kentucky. E models were conversions from existing CH-47C model airframes. The MH-47E has similar capabilities as the MH-47D, but includes an increased fuel capacity similar to the CH-47SD and terrain following/terrain avoidance radar.^[14]
In 1995, the Royal Air Force ordered eight Chinook HC3s, effectively a low cost version of the MH-47E for the special forces operations role. They were delivered in 2001 but never entered operational service due to technical issues with their avionics fit, unique to the HC3. In 2008, work started to downgrade the HC3s to HC2 standard, to enable them to enter service.^[15]

[ CH-47F

Soldiers prepare to board a CH-47F at the National Training Center, Fort Irwin, Calif., November 2007.



The CH-47F, an upgraded D model, first flew in 2001. The first production model was rolled out on June 15, 2006 at the Boeing facility in Ridley Park, Pennsylvania, and had its maiden flight on October 23, 2006.^[16] The CH-47F was designed to extend the service life of the Chinook class beyond 2030. Among its upgrades are new 4,868 shaft horsepower Honeywell engines, improved avionics, and an upgraded airframe with larger single-piece sections to reduce part count and need for fasteners.^[17] The new milled construction will reduce vibrations, eliminate points of joint flexing, and reduce the need for inspections and repairs, and reduce maintenance costs. It is also expected to increase service life.^[18] The CH-47F can fly at speeds of over 175 mph (282 km/h) with a payload of more than 21,000 lb (9,530 kg).^[19] The improved avionics include a Rockwell Collins Common Avionics Architecture System (CAAS) cockpit, and BAE Systems' Digital Advanced Flight Control System (DAFCS).^[17]
Boeing has delivered 48 F-model helicopters to the United States Army; on August 26, 2008, Boeing announced that the Army has signed a five-year contract, worth over $4.8 billion for 191 more, plus 24 options.^[19] In February 2007, the Netherlands were the first international customer to order the F model; six helicopters were ordered to expand their current fleet to 17. These six helicopters will be equipped with an upgraded version of the Honeywell Avionics Control Management System (ACMS) cockpit.^[20]

-

[ MH-47G


MH-47G Chinook, during the aircraft's rollout ceremony 6 May 2007 at Boeing.



The MH-47G Special Operations Aviation (SOA) version is currently being delivered to the U.S. Army. It is similar to the MH-47E, but features a more sophisticated avionics including a digital Common Avionics Architecture System (CAAS). The CAAS is common glass cockpit used by different helicopters such as MH-60K/Ls, CH-53E/Ks, and ARH-70As.^[21] The MH-47G will also incorporate all of the new sections of the CH-47F.^[22]
Based on operational experience in Afghanistan, the CH-47 was found to be an effective substitute for the UH-60 Black Hawk as an assault helicopter. With its larger payload, range, and higher operating speed, one Chinook can replace up to five UH-60s in this role as an air assault transport.^[23]

[ HH-47


On November 9, 2006, the HH-47, a new variant of the Chinook based on the MH-47G, was selected by the U.S. Air Force as the winner of the Combat Search and Rescue (CSAR-X) competition. Four development HH-47s will be built, with the first of 141 production aircraft to enter service in 2012.^[24][25] However, as of February 2007 this contract award has come under scrutiny by the GAO and the USAF may recompete the CSAR-X project.^[26]

[ Operators

Main article: List of CH-47 Chinook operators


-
CH-47 operators


_]