AH-1 Cobra: Wikis

Advertisements
  
  

Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.

Encyclopedia

From Wikipedia, the free encyclopedia

For an overview of the whole Huey family of aircraft see Bell Huey
AH-1 HueyCobra/Cobra
A Bell AH-1G HueyCobra
Role Attack helicopter
Manufacturer Bell Helicopter
First flight 7 September 1965
Introduction 1967
Status Active service
Primary users United States Army
Japan Self Defense Forces
Republic of Korea Army
Israeli Air Force
Produced 1967-present
Number built 1,116
Unit cost US$11.3 million (1995) (AH-1 HueyCobra)[1]
Developed from UH-1 Iroquois
Variants AH-1 SeaCobra/SuperCobra
Bell 309 KingCobra

The AH-1 Cobra (company designation: Bell 209) is a two-bladed, single engine attack helicopter manufactured by Bell. It shares a common engine, transmission and rotor system with the older UH-1 Iroquois. The AH-1 is also referred to as the HueyCobra or Snake.

The AH-1 was the backbone of the United States Army's attack helicopter fleet, but has been replaced by the AH-64 Apache in Army service. Upgraded versions continue to fly with the militaries of several other nations. The AH-1 twin engine versions remain in service with United States Marine Corps as the service's primary attack helicopter. Surplus AH-1 helicopters have been converted for fighting forest fires. The United States Forest Service refers to their program as the Firewatch Cobra. Garlick Helicopters also converts surplus AH-1s for forest firefighting under the name, FireSnake.[2]

Contents

Development

Advertisements

Background

Closely related with the development of the Bell AH-1 is the story of the Bell UH-1 Iroquois—predecessor of the modern helicopter, icon of the Vietnam War and still one of the most numerous helicopter types in service today.

The UH-1 made the theory of air cavalry practical, as the new tactics called for US forces to be highly mobile across a wide area. Unlike before, they would not stand and fight long battles, and they would not stay and hold positions. Instead, the plan was that the troops carried by fleets of UH-1 Hueys would range across the country, to fight the enemy at times and places of their own choice.[3]

It soon became clear that the unarmed troop helicopters were vulnerable against ground fire from Việt Cộng and North Vietnamese troops, particularly as they came down to drop their troops in a landing zone. Without friendly support from artillery or ground forces, the only way to pacify a landing zone was from the air, preferably with a machine that could closely escort the transport helicopters, and loiter over the landing zone as the battle progressed. By 1962 a small number of armed UH-1As were used as escorts, armed with multiple machine guns and rocket mounts.[4]

The massive expansion of American military presence in Vietnam opened a new era of war from the air. The linchpin of US Army tactics were the helicopters, and the protection of those helicopters became a vital role.[5]

Bell 207 Sioux Scout

Bell Model 207 Sioux Scout

Bell had been investigating helicopter gunships since the late 1950s, and had created a mockup of its D 255 helicopter gunship concept, named "Iroquois Warrior". In June 1962, Bell displayed the mockup to Army officials, hoping to solicit funding for further development. The D 255 Iroquois Warrior was planned to be a purpose-built attack aircraft based on the UH-1B components with a new, slender airframe and a two-seat, tandem cockpit. It featured a grenade launcher in a ball turret on the nose, a 20 mm belly-mounted gun pod, and stub wings for mounting rockets or SS-10 anti-armor missiles.[6]

The Army was interested and awarded Bell a proof of concept contract in December 1962. Bell modified a Model 47 into the sleek Model 207 Sioux Scout which first flew in July 1963.[7] The Sioux Scout had all the key features of a modern helicopter gunship–a tandem cockpit, stub wings for weapons, and a chin-mounted gun turret. After evaluating the Sioux Scout in early 1964, the Army was impressed, but also believed the Sioux Scout was too small, underpowered, unsophisticated, and fragile to be of practical use.[7]

AAFSS

Army's solution to the shortcomings of the Sioux Scout was to launch the Advanced Aerial Fire Support System (AAFSS) competition.[7] The AAFSS requirement would give birth to the Lockheed AH-56 Cheyenne–a heavy battlefield helicopter that would prove to be over-ambitious, over-complex and over-budget, before being canceled 10 years later in 1972.[7] The Cheyenne program developed future technology and demonstrated some impressive performance, but was never made to work as a functional gunship. It served to underline an important rule of the combat helicopter–survival would be ensured only by the right mix of speed, agility and weapons.

Model 209

Bell 209 prototype of the AH-1 Cobra series, with skids retracted (FAA no. N209J).

At the same time, despite the Army's preference for the AAFSS–for which Bell Helicopter was not selected to compete–Bell stuck with their own idea of a smaller and lighter gunship.[7] In January 1965 Bell invested $1 million to proceed with a new design.

Mating the proven transmission, the "540" rotor system of the UH-1C augmented by a Stability Control Augmentation System (SCAS), and the T53 turboshaft engine of the UH-1 with the design philosophy of the Sioux Scout, Bell produced the Model 209.[7] Bell's Model 209 largely resembled its "Iroquois Warrior" mockup.[8]

In Vietnam, events were also advancing in favor of the Model 209. Attacks on US forces were increasing, and by the end of June 1965 there were already 50,000 US ground troops in Vietnam.[7]

1965 was also the deadline for AAFSS selection, but the program was stuck in technical difficulties and political bickering. The U.S. Army needed an interim gunship for Vietnam and it asked five companies to provide a quick solution. Submissions came in for armed variants of the Boeing-Vertol ACH-47A, Kaman HH-2C Tomahawk, Piasecki 16H Pathfinder, Sikorsky S-61, and the Bell 209.[7]

On 3 September 1965 Bell rolled out the prototype, and four days later it made its maiden flight, only eight months from the go-ahead. In April 1966, the Model 209 won an evaluation against the other rival helicopters. Then the Army signed the first production contract for 110 aircraft.[7]

The Bell 209 demonstrator was used for the next six years to test weapons and fit of equipment. It had been modified to the match AH-1 production standard by the early 1970s. The demonstrator was retired to the Patton Museum at Fort Knox, KY and converted to approximately its original appearance.[8]

Into production

The Bell 209 design was modified for production. The retractable skids were replaced by simpler fixed skids. A new wide-blade rotor was featured. For production, a plexiglass canopy replaced the 209's armored glass canopy which was heavy enough to harm performance.[8] Other changes were incorporated after entering service. The main one of these was moving the tail rotor from the helicopter's left side to the right for improved effectiveness of the rotor.[9]

The U.S. Marine Corps was interested in the Cobra and ordered an improved twin-engined version in 1968 under the designation AH-1J. This would lead to more twin-engine variants.[10] In 1972, the Army sought improved anti-armor capability. Under the Improved Cobra Armament Program (ICAP), trials of eight AH-1s fitted with TOW missiles were conducted in 1973. After passing qualification tests the following year, Bell was contracted with upgrading AH-1Gs to the TOW-capable AH-1Q configuration. A more powerful T53 engine and transmission was added from 1976 resulting in the AH-1S version. The AH-1S was upgraded in three steps, culminating with the AH-1F.[7][11]

Operational history

Bell AH-1G over Vietnam
AH-1Q Cobra in Fort Hood, Texas
A late-model AH-1 Cobra at ILA 2006 in Berlin

United States

By June 1967, the first AH-1G HueyCobras had been delivered. Originally designated as UH-1H, the "A" for attack designation was soon adopted and when the improved UH-1D became the UH-1H, the HueyCobra became the AH-1G.[7] The AH-1 was initially considered a variant of the H-1 line, resulting in the G series letter.

AH-1 Cobras were in use by the Army during the Tet offensive in 1968 and through the end of the Vietnam War. Huey Cobras provided fire support for ground forces, escorted transport helicopters and other roles, including aerial rocket artillery (ARA) battalions in the two Airmobile divisions. They also formed "hunter killer" teams by pairing with OH-6A scout helicopters. A team featured one OH-6 flying slow and low to find enemy forces. If the OH-6 drew fire, the Cobra could strike at the then revealed enemy.[8] Bell built 1,116 AH-1Gs for the US Army between 1967 and 1973, and the Cobras chalked up over a million operational hours in Vietnam.[7] Approximately 300 AH-1s were lost to combat and accidents during the war.[8]

The US Marine Corps used AH-1G Cobras in Vietnam for a short time before acquiring twin-engine AH-1J Cobras.

AH-1 Cobras were deployed for Operation Urgent Fury, the invasion of Grenada in 1983, flying close-support and helicopter escort missions. Army Cobras participated in the US invasion of Panama in 1989, during Operation Just Cause.[8]

During Operation Desert Shield (1990) and Operation Desert Storm (Jan-Feb 1991), the Cobras and SeaCobras deployed in a support role. The USMC deployed 91 SeaCobras and the US Army 140 Cobras, generally fitted with engine inlet sand filters and operating from forward, dispersed sites in the desert. Three AH-1s were lost in accidents during fighting and afterward.[8] Cobras destroyed hundreds of Iraqi armored vehicles and other targets in the fighting, though the Army relegated the Cobra to the patrol and scout roles.

Army Cobras provided support for the US humanitarian intervention during Operation Restore Hope in Somalia in 1993. They were also employed during the US invasion of Haiti in 1994. US Cobras were also used in operations throughout the 1990s.[8] In December 1995, Cobras deployed to Bosnia with the U.S. Army's 1st Armored Division as a part of Operation Joint Endeavor.[citation needed]

The US Army phased out the AH-1 during the 1990s and retired the AH-1 from active service in March 1999, offering them to NATO allies.[7][12] The Army retired the AH-1 from reserves in September 2001. The retired AH-1s have been passed to other nations and to the USDA Forest Service.[7] AH-1 Cobras continue to be in service with the US military, by the US Marine Corps, which operate twin-engine AH-1 SuperCobras.

Israel

The Israeli Air Force named its Cobras as the "Tzefa" (צפע), Hebrew for Viper.[13] Since the mid-1970s Lebanon has been Israel's most active front. The Cobra helicopter's unique abilities and its precision weapons have made it perfect for the Lebanese theatre and IAF Cobras have been a constant feature of the fighting for more than 20 years. The first Cobra attack took place on 9 May 1979, near Tyre. Having crossed the border over the Mediterranean at dusk, two AH-1s scored direct hits with 2 missiles fired by each helicopter.

Cobra helicopter gunships were also used widely by the Israeli Air Force in the 1982 Lebanon War to destroy Syrian armor and fortification. IAF Cobras destroyed dozens of Syrian armored fighting vehicles, including many of the modern Soviet T-72 tanks. As part of their service in southern Lebanon the Cobras were very active in Israel's major operations against Hezbullah in operations "Accountability" and "Grapes of Wrath".

Pakistan

Pakistan was supplied with around 20 AH-1F gunships in 1983, these were later upgraded with the C-NITE thermal imaging package. Prior to that Iran had donated some AH-1 helicopters to Pakistan in mid 1970s, which Pakistan used as its main gunship helicopters against insurgents during the Balochistan conflict.[14] The recent insurgencies in the Waziristan regions have seen Pakistani AH-1 gunships in action against Taliban and Al Qaeda fighters as well as their tribal allies. Pakistani gunships have also been used in operations against tribal uprisings in the Balochistan province, supporting the Pakistan Army against well-armed Bugti and Marri tribesmen under the late Nawab Akbar Khan Bugti and the Balochistan Liberation Army, since the mid-2000s.[15]

Pakistan has several AH-1F and AH-1S Cobra attack helicopters. Sustainment of these aircraft is difficult, but possible through commercial channels. Additionally, the U.S. Government will use $75 million in FY 2009 Pakistan Counterinsurgency Funds to update a portion of the existing Cobra fleet. Pakistan will likely seek to replace its current AH-1 Cobras when the AH-1Z becomes available for export, probably in 2015.[16]

US Forest Service

In 2003, the US Forest Service acquired 25 retired AH-1Fs from the US Army.[7] These have been designated Bell 209 and are being converted into Firewatch Cobras with infared and low light sensors and systems for real time fire monitoring.[17][18] The Florida Department of Forestry has also acquired 3 AH-1Ps from US Army. These are called Bell 209 "Firesnakes" and are equipped to carry a water/fire retardant system.[7]

Variants

Single-engine

JGSDF AH-1S
U.S. Forest Service Bell 209 on the Bar Complex Fire in California. USFS photo.
Bell 209 
Original AH-1G prototype with retractable skid landing gear. This model number is also used by the FAA for the civilian registration of former U.S. Army AH-1s used in firefighting service.
AH-1G HueyCobra 
Initial 1966 production model gunship for the US Army, with one 1,400 shp (1,000 kW) Avco Lycoming T53-13 turboshaft.
JAH-1G HueyCobra 
One helicopter for armament testing including Hellfire missiles and multi-barrel cannon.[19]
TH-1G HueyCobra 
Two-seat dual-control trainer.[19]
Z.14 HueyCobra 
Spanish Navy designation of the AH-1G.[19]
YAH-1Q 
Eight AH-1Gs with XM26 Telescopic Sight Unit (TSU) and two M56 TOW 4-pack launchers.[8]
AH-1Q HueyCobra 
Equipped with the M65 TOW/Cobra missile subsystem, M65 Telescopic Sight Unit (TSU), and M73 Reflex sight. All future versions will be equipped with the TSU and be equipped to fire the TOW missile subsystem.
YAH-1R 
AH-1G powered by a T53-L-703 engine without TOW system.[8]
YAH-1S 
AH-1Q upgrade and TOW system.[8]
AH-1S 
The baseline AH-1S is an AH-1Q upgraded with a 1,800 shp (1,300 kW) T53-L-703 turboshaft engine. The AH-1S is also referred to as the "Improved AH-1S", "AH-1S Modified", or "AH-1S(MOD)" prior to 1988. (Prior to 1988, all upgraded aircraft were referred to as variants of the AH-1S.)[8]
AH-1P 
100 production aircraft with composite rotors, flat plate glass cockpit, and improved cockpit layout for nap-of-earth (NOE) flight. The AH-1P is also referred to as the "Production AH-1S", or "AH-1S(PROD)" prior to 1988. These improvements are considered Step 1 of the AH-1S upgrade program.[8]
AH-1E 
98 production aircraft with the Enhanced Cobra Armament System (ECAS) featuring the M97A1 armament subsystem with a three-barreled M197 20 mm cannon. The AH-1E is also referred to as the "Upgunned AH-1S", or "AH-1S(ECAS)" prior to 1988. These improvements are considered Step 2 of the AH-1S upgrade program.[8] AH-1E aircraft included the M147 Rocket Management Subsystem (RMS) to fire 2.75-inch (70 mm) rockets.[20]
AH-1F 
143 production aircraft and 387 converted AH-1G Cobras. The AH-1F incorporates all Step 1 and 2 upgrades to the AH-1S as well an M143 Air Data Subsystem (ADS), a laser rangefinder and tracker, an infrared jammer mounted above the engine exhaust, and an infrared suppressing engine exhaust system. The AH-1F is also referred to as the "Modernized AH-1S", "AH-1S Modernized Cobra", or "AH-1S(MC)" prior to 1988.
Model 249 
Experimental demonstrator version fitted with a four-bladed rotor system, an uprated engine and experimental equipment, including Hellfire missiles.[21]
Bell 309 KingCobra 
Experimental version. One of two 309s produced was powered by a Lycoming T-55-L-7C engine.[22]

Twin-engine

Operators

Operators of the AH-1 single-engined variant are shown in dark blue, the twin-engined variant in green and both variants in light blue.

Current operators

Two Pakistani Army AH-1S Cobras at AVN Base, Multan
Three Israeli AH-1F Cobras over Masada
USFS Bell 209 at Fox Field during the California wildfires of October 2007
 Bahrain
  • Bahrain Air Force acquired 24 AH-1Ps and 6 TAH-1P trainers.[8] Bahrain has 10 AH-1Es, 6 AH-1Ps and 6 TAH-1Ps in inventory as of January 2010.[23]
 Israel
  • Israeli Air Force has 54 AH-1 "Tzefa" צפע ("Viper"), consisting of 5 AH-1G, 30 AH-1S, 6 AH-1E, and 13 AH-1F variants in inventory as of January 2010.[23]
 Japan
 Jordan
 Pakistan
  • Pakistan Army received 20 AH-1S Cobras in the 1980s (later upgraded to AH-1F) and ordered more AH-1Fs in 2004.[8] Pakistan has 18 AH-1S and 8 AH-1F Cobras in use as of January 2010.[23] Pakistan ordered more Cobras in 2008 and received 14 AH-1s from United States in March 2010.[25][26]
 South Korea
 Thailand
 Turkey
  • Turkish Army received 32 used AH-1P/S Cobras. These were upgraded to AH-1F standards.[7] The Turkish Army has 23 AH-1P Cobras in inventory as of 2010.[23]
 United States
  • U.S. Forest Service (25 AH-1Fs, converting to Bell 209 Firewatch Cobras)[17]
  • Florida Department of Forestry (3 AH-1Ps, converting to Bell 209 "Firesnakes")[7]

For operators of AH-1J, AH-1T, AH-1W, AH-1Z and other twin-engine variants, see AH-1 SuperCobra.

Former operators

 Spain
  • Spanish Navy purchased eight new-build AH-1Gs, designating the type the "Z-14". These were equipped with the M35 20 mm cannon system, and were used to support coastal patrol boats. Four of these were lost in accidents. The remaining helicopters were retired in 1985 with three sent back to the US, and one kept in storage in Spain.[27]
 United States

Specifications

AH-1G HueyCobra

AH-1G.jpg

Data from Modern Military Aircraft[28]

General characteristics

  • Crew: 2 - one pilot, one CPG (co-pilot/gunner)
  • Length: 44 ft 5 in (13.4 m)
  • Rotor diameter: 44 ft (13.4 m)
  • Height: 13 ft 5 in (4.1 m)
  • Empty weight: 6,073 lb (2,754 kg)
  • Max takeoff weight: 9,500 lb (4,309 kg)
  • Powerplant:Lycoming T53-L-13 turboshaft, 1,100 shp (820 kW)
  • Rotor system: 2 blades on main rotor

Performance

Armament

  • 2 × 7.62 mm (0.308 in) multi-barrel Miniguns, or 2 × M129 40 mm Grenade launchers, or one of each, in the M28 turret. (When one of each was mounted, the minigun was mounted on the right side of the turret, due to feeding problems.)
  • 2.75 in (70 mm) rockets - 7 rockets mounted in the M158 launcher or 19 rockets in the M200 launcher
  • M18 7.62 mm Minigun pod or XM35 armament subsystem with XM195 20 mm cannon

AH-1F "Modernized" Cobra

Bell AH-1F SUPER COBRA.png

Data from Verier[29]

General characteristics

  • Crew: 2 - one pilot, one CPG (co-pilot/gunner)
  • Length: 53 ft (16.1 m) (with both rotors turning)
  • Rotor diameter: 44 ft (13.6 m)
  • Height: 13 ft 5 in (4.1 m)
  • Empty weight: 6,600 lb (2,993 kg)
  • Max takeoff weight: 10,000 lb (4,500 kg)
  • Powerplant:Lycoming T53-L-703 turboshaft, 1,800 shp (1,300 kW)
  • Rotor system: 2 blades on main rotor
  • Fuselage length: 44 ft 7 in (13.6 m)
  • 'Stub wing span: 10 ft 4 in (3.15 m)

Performance

Armament

  • M197 3-barreled 20 mm Gatling type cannon
  • Hydra 70 2.75 in (70 mm) rockets - 7 rockets mounted in the M260 launcher or 19 rockets in the M261 launcher[30]
  • TOW Missiles - 4 or 8 missiles mounted in two-missile launchers on each hardpoint

See also

Related development

Comparable aircraft

Related lists

References

Notes
  1. ^ Military aircraft prices
  2. ^ Stephens, Ernie. "Recycling helicopters from military service to public service." Rotor & Wing, November 2008. Retrieved on 12 October 2009.
  3. ^ Wheeler 1987, pp. 62-64.
  4. ^ Wheeler 1987, pp. 57-62, 64-65.
  5. ^ Wheeler 1987, pp. 60-61.
  6. ^ Verier 1990, pp. 12-17.
  7. ^ a b c d e f g h i j k l m n o p q r s Donald, David and March, Daniel. Modern Battlefield Warplanes. AIRtime Publishing Inc, 2004. ISBN 1-880588-76-5.
  8. ^ a b c d e f g h i j k l m n o p q r s Bishop, Chris. Huey Cobra Gunships. Osprey Publishing, 2006. ISBN 1-84176-984-3.
  9. ^ Verier 1990, p. 44.
  10. ^ Verier 1990, pp. 86-88.
  11. ^ Verier 1990, pp. 57, 59-61.
  12. ^ Army retires Cobras from active force. U.S. Army, 31 March 1999.
  13. ^ "Bell AH-1 Huey-Cobra". Israeli Air Force. http://www.iaf.org.il/Templates/Aircraft/Aircraft.IN.aspx?lang=EN&lobbyID=69&folderID=82&docfolderID=209&docID=18311&currentPageNumber=3. Retrieved 2007-03-15. 
  14. ^ http://www.surfthechannel.com/episode/63638/411274.html
  15. ^ http://usmanansari.com/id36.html
  16. ^ http://propublica.s3.amazonaws.com/assets/pakistan_contracts/121409_Pakistan_assistance_strategy%20reportFINAL.pdf
  17. ^ a b Firewatch Helicopter page. US Forest Service, 2004.
  18. ^ Bell 209 Firewatch Cobra on USDA Forest Service site
  19. ^ a b c Donald, David. The Complete Encyclopedia of World Aircraft. Barnes & Nobel Books, 1997. ISBN 0-7607-0592-5.
  20. ^ McGowen, Stanley S. Helicopters: An Illustrated History of Their Impact, p. 159. Santa Barbara, Calif.:ABC-CLIO, 2005. ISBN 1-85109-468-7.
  21. ^ Verier 1990, pp. 72-76.
  22. ^ Goebel, Greg. Model 309 Kingcobra / Model 409 AAH (YAH-63). Vectorsite.net, 1 December 2008.
  23. ^ a b c d e f g h "World Military Aircraft Inventory". 2010 Aerospace Source Book. Aviation Week and Space Technology, January 2010.
  24. ^ "Apache wins Japan deal", Flight International, 4 September 2001.
  25. ^ "Pak Army gets fleet of Cobra choppers". Daily Times Monitor, 17 March 2010.
  26. ^ "US delivers Cobra helicopter gunships to Pakistan". Sify News, 16 March 2010.
  27. ^ Goebel, Greg. International Cobra Sales. Vectorsite.net, 1 December 2008.
  28. ^ Gunston, Bill: The Illustrated Encyclopedia of the World's Modern Military Aircraft, p. 205. Crescent Books, New York, NY USA, ca. 1978. ISBN 978-0-517-22477-9
  29. ^ Verier 1990, p. 184.
  30. ^ U.S. Army Helicopter Weapon Systems
Bibliography
  • Gunston, B. and Michael Spick. Modern Fighting Helicopters, pp. 104–05. New York: Crescent Books, 1986. ISBN 0-517-61349-2.
  • International Air Power Review, Volume 12. AIRtime Publishing, 2004. ISBN 1-880588-77-3.
  • Nolan, Keith W. Into Laos: Dewey Canyon II/Lam Son 719, Vietnam 1971. Presidio Press, 1986. ISBN 0891412476.
  • Richardson, Doug. Modern Fighting Aircraft, Volume 13, AH-1 Cobra. New York: Prentice Hall, 1987. ISBN 0-13-020751-9.
  • Verier, Mike. Bell AH-1 Cobra. Osprey Publishing, 1990. ISBN 0-85045-934-6.
  • Wheeler, Howard A. Attack Helicopters, A History of Rotary-Wing Combat Aircraft. The Nautical and Aviation Publishing Company, 1987. ISBN 0933852-52-5.

External links


Advertisements






Got something to say? Make a comment.
Your name
Your email address
Message