AH-1Z Viper
Encyclopedia
The Bell AH-1Z Viper is a twin-engine attack helicopter based on the AH-1W SuperCobra, that was developed for the United States Marine Corps
. The AH-1Z features a four-blade, bearingless, composite main rotor system, uprated transmission, and a new target sighting system. The AH-1Z is part of the H-1 upgrade program
. It is also called "Zulu Cobra" in reference to its variant letter.
equipped with the four-blade main rotor system from the Bell 412
. This helicopter demonstrated Bell's Cobra II design at the Farnborough Airshow in 1980. The Cobra II was to be equipped with Hellfire
missiles, a new targeting system and improved engines. Later came the Cobra 2000 proposal which included General Electric T700 engines and a four-blade rotor. This design drew interest from the US Marine Corps, but funding was not available. In 1993, Bell proposed an AH-1W-based version for the UK's new attack helicopter program. The derivative design, named CobraVenom, featured a modern digital cockpit and could carry TOW
s, Hellfire or Brimstone
missiles. The CobraVenom design was altered in 1995 by changing to a four-blade rotor system. The design lost to the AH-64D later that year however.
Bell participated in a joint Bell-Government integrated test team during the engineering manufacturing development (EMD) phase of the H-1 program. The AH-1Z program progressed slowly from 1996 to 2003 largely as a research and development operation. The existing two-blade semi-rigid, teetering rotor system is being replaced with a four-blade, hingeless, bearingless rotor system. The four-blade configuration provides improvements in flight characteristics including increased flight envelope, maximum speed, vertical rate-of-climb, payload and reduced rotor vibration level.
The AH-1Z first flew on 8 December 2000. Bell delivered three prototype aircraft to Naval Air Systems Command
(NAVAIR) at Naval Air Station Patuxent River
in July 2002, for the flight test phase of the program. Low-rate initial production began in October 2003, with deliveries to run through 2018. In February 2008, the United States Navy
adjusted the contract, with the last 40 AH-1Zs to be built as new airframes instead of the previously planned rebuild of AH-1Ws. In September 2008, the Navy requested an additional 46 airframes for the Marine Corps, bringing the total number ordered to 226. In 2010, the Marine Corps plans to order 189 AH-1Zs with 58 of them being new airframes, with deliveries to continue until 2019. On 10 December, the Department of the Navy approved full-rate production.
The AH-1Z incorporates new rotor technology with upgraded military avionics, weapons systems, and electro-optical sensors in an integrated weapons platform. It has improved survivability and can find targets at longer ranges and attack them with precision weapons.
The AH-1Z's new bearingless, hingeless rotor system has 75% fewer parts than that of four-bladed articulated systems. The blades are made of composites, which have an increased ballistic survivability, and there is a semiautomatic folding system for stowage aboard amphibious assault ship
s. Its two redesigned wing stubs are longer, with each adding a wing-tip station for a missile such as the AIM-9 Sidewinder
. Each wing has two other stations for 2.75-inch (70 mm) Hydra 70
rocket pods, or AGM-114 Hellfire
quad missile launchers. The Longbow radar can also be mounted on a wing tip station.
The Z-model's integrated avionics system (IAS) has been developed by Northrop Grumman. The system includes two mission computers and an automatic flight control system. Each crew station has two 8x6-inch multifunction liquid crystal display
s (LCD) and one 4.2x4.2-inch dual function LCD display. The communications suite combines a US Navy RT-1824 integrated radio, UHF/VHF, COMSEC and modem in a single unit. The navigation suite includes an embedded GPS
inertial navigation system (EGI), a digital map system and a low-airspeed air data subsystem, which allows weapons delivery when hovering.
The crew are equipped with the Thales
"Top Owl" helmet-mounted sight and display system. The Top Owl has a 24-hour day/night capability and a binocular display with a 40° field of view. Its visor projection provides forward looking infrared
(FLIR) or video imagery. The AH-1Z has survivability equipment including the Hover Infrared Suppression System (HIRSS) to cover engine exhausts, countermeasure dispensers, radar warning, incoming/on-way missile warning and on-fuselage laserspot warning systems.
The Lockheed Martin
target sight system (TSS) incorporates a third-generation FLIR sensor. The TSS provides target sighting in day, night or adverse weather conditions. The system has various view modes and can track with FLIR or by TV. The same system is also used on the UH-1Y Venom
and the KC-130J Harvest HAWK.
In February 2008, the AH-1Z and UH-1Y began the second and final portion of OPEVAL testing. AH-1Z testing was stopped in 2008 due to issues with its targeting systems. The AH-1Z was finally declared combat-ready in September 2010.
United States Marine Corps
The United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...
. The AH-1Z features a four-blade, bearingless, composite main rotor system, uprated transmission, and a new target sighting system. The AH-1Z is part of the H-1 upgrade program
H-1 upgrade program
The H-1 upgrade program refers to the United States Marine Corps's program to develop the AH-1Z Viper and UH-1Y Venom to replace its aging fleets of AH-1W SuperCobras and UH-1N Twin Hueys. The former is a twin-engine attack helicopter, while the latter is a medium-sized utility helicopter, also...
. It is also called "Zulu Cobra" in reference to its variant letter.
Background
Aspects of the AH-1Z date back to the Bell 249 in 1979, which was basically an AH-1SAH-1 Cobra
The Bell AH-1 Cobra is a two-bladed, single engine attack helicopter manufactured by Bell Helicopter. It shares a common engine, transmission and rotor system with the older UH-1 Iroquois...
equipped with the four-blade main rotor system from the Bell 412
Bell 412
The Bell 412 is a utility helicopter manufactured by Bell Helicopter. It is a development of the Bell 212 model, the major difference being the composite four-blade main rotor.-Design and development:...
. This helicopter demonstrated Bell's Cobra II design at the Farnborough Airshow in 1980. The Cobra II was to be equipped with Hellfire
AGM-114 Hellfire
The AGM-114 Hellfire is an air-to-surface missile developed primarily for anti-armor use. It has multi-mission, multi-target precision-strike capability, and can be launched from multiple air, sea, and ground platforms. The Hellfire missile is the primary 100 lb-class air-to-ground precision...
missiles, a new targeting system and improved engines. Later came the Cobra 2000 proposal which included General Electric T700 engines and a four-blade rotor. This design drew interest from the US Marine Corps, but funding was not available. In 1993, Bell proposed an AH-1W-based version for the UK's new attack helicopter program. The derivative design, named CobraVenom, featured a modern digital cockpit and could carry TOW
Wire-guided missile
A wire-guided missile is a missile that is guided by signals sent to it via thin wires connected between the missile and its guidance mechanism, which is located somewhere near the launch site. As the missile flies, the wires are reeled out behind it...
s, Hellfire or Brimstone
Brimstone missile
Brimstone is an air-launched anti-tank missile developed by MBDA for Britain's Royal Air Force. It was originally intended for "fire and forget" use against mass formations of enemy armour, using a millimetre wave seeker to ensure accuracy even against moving targets...
missiles. The CobraVenom design was altered in 1995 by changing to a four-blade rotor system. The design lost to the AH-64D later that year however.
H-1 upgrade program
In 1996, the USMC launched the H-1 upgrade program by signing a contract with Bell Helicopter for upgrading 180 AH-1Ws into AH-1Zs and upgrading 100 UH-1Ns into UH-1Ys. The H-1 program created completely modernized attack and utility helicopters with considerable design commonality to reduce operating costs. The AH-1Z and UH-1Y share a common tail boom, engines, rotor system, drive train, avionics architecture, software, controls and displays for over 84% identical components.Bell participated in a joint Bell-Government integrated test team during the engineering manufacturing development (EMD) phase of the H-1 program. The AH-1Z program progressed slowly from 1996 to 2003 largely as a research and development operation. The existing two-blade semi-rigid, teetering rotor system is being replaced with a four-blade, hingeless, bearingless rotor system. The four-blade configuration provides improvements in flight characteristics including increased flight envelope, maximum speed, vertical rate-of-climb, payload and reduced rotor vibration level.
The AH-1Z first flew on 8 December 2000. Bell delivered three prototype aircraft to Naval Air Systems Command
Naval Air Systems Command
The Naval Air Systems Command provides material support for aircraft and airborne weapon systems for the United States Navy. NAVAIR was established in 1966 as the successor to the Navy's Bureau of Naval Weapons . Current Commander, Naval Air Systems Command, is Vice Adm. David Architzel since May...
(NAVAIR) at Naval Air Station Patuxent River
Naval Air Station Patuxent River
"Pax River" redirects here. For the river, see Patuxent River.Naval Air Station Patuxent River , also known as NAS Pax River, is a United States Naval Air Station located in St. Mary's County, Maryland on the Chesapeake Bay near the mouth of the Patuxent River. It is home to the U.S...
in July 2002, for the flight test phase of the program. Low-rate initial production began in October 2003, with deliveries to run through 2018. In February 2008, the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
adjusted the contract, with the last 40 AH-1Zs to be built as new airframes instead of the previously planned rebuild of AH-1Ws. In September 2008, the Navy requested an additional 46 airframes for the Marine Corps, bringing the total number ordered to 226. In 2010, the Marine Corps plans to order 189 AH-1Zs with 58 of them being new airframes, with deliveries to continue until 2019. On 10 December, the Department of the Navy approved full-rate production.
Design
The AH-1Z's new bearingless, hingeless rotor system has 75% fewer parts than that of four-bladed articulated systems. The blades are made of composites, which have an increased ballistic survivability, and there is a semiautomatic folding system for stowage aboard amphibious assault ship
Amphibious assault ship
An amphibious assault ship is a type of amphibious warfare ship employed to land and support ground forces on enemy territory by an amphibious assault...
s. Its two redesigned wing stubs are longer, with each adding a wing-tip station for a missile such as the AIM-9 Sidewinder
AIM-9 Sidewinder
The AIM-9 Sidewinder is a heat-seeking, short-range, air-to-air missile carried mostly by fighter aircraft and recently, certain gunship helicopters. The missile entered service with United States Air Force in the early 1950s, and variants and upgrades remain in active service with many air forces...
. Each wing has two other stations for 2.75-inch (70 mm) Hydra 70
Hydra 70
The Hydra 70 rocket is a weapon derived from the 70 mm Mk 4/Mk 40 Folding-Fin Aerial Rocket developed by the United States Navy for use as a free-flight aerial rocket in the late 1940s.-Overview:...
rocket pods, or AGM-114 Hellfire
AGM-114 Hellfire
The AGM-114 Hellfire is an air-to-surface missile developed primarily for anti-armor use. It has multi-mission, multi-target precision-strike capability, and can be launched from multiple air, sea, and ground platforms. The Hellfire missile is the primary 100 lb-class air-to-ground precision...
quad missile launchers. The Longbow radar can also be mounted on a wing tip station.
The Z-model's integrated avionics system (IAS) has been developed by Northrop Grumman. The system includes two mission computers and an automatic flight control system. Each crew station has two 8x6-inch multifunction liquid crystal display
Liquid crystal display
A liquid crystal display is a flat panel display, electronic visual display, or video display that uses the light modulating properties of liquid crystals . LCs do not emit light directly....
s (LCD) and one 4.2x4.2-inch dual function LCD display. The communications suite combines a US Navy RT-1824 integrated radio, UHF/VHF, COMSEC and modem in a single unit. The navigation suite includes an embedded GPS
Global Positioning System
The Global Positioning System is a space-based global navigation satellite system that provides location and time information in all weather, anywhere on or near the Earth, where there is an unobstructed line of sight to four or more GPS satellites...
inertial navigation system (EGI), a digital map system and a low-airspeed air data subsystem, which allows weapons delivery when hovering.
The crew are equipped with the Thales
Thales Group
The Thales Group is a French electronics company delivering information systems and services for the aerospace, defense, transportation and security markets...
"Top Owl" helmet-mounted sight and display system. The Top Owl has a 24-hour day/night capability and a binocular display with a 40° field of view. Its visor projection provides forward looking infrared
Forward looking infrared
Forward looking infrared cameras, typically used on military aircraft, use an imaging technology that senses infrared radiation.The sensors installed in forward looking infrared cameras, as well as those of other thermal imaging cameras, use detection of infrared radiation, typically emitted from a...
(FLIR) or video imagery. The AH-1Z has survivability equipment including the Hover Infrared Suppression System (HIRSS) to cover engine exhausts, countermeasure dispensers, radar warning, incoming/on-way missile warning and on-fuselage laserspot warning systems.
The Lockheed Martin
Lockheed Martin
Lockheed Martin is an American global aerospace, defense, security, and advanced technology company with worldwide interests. It was formed by the merger of Lockheed Corporation with Martin Marietta in March 1995. It is headquartered in Bethesda, Maryland, in the Washington Metropolitan Area....
target sight system (TSS) incorporates a third-generation FLIR sensor. The TSS provides target sighting in day, night or adverse weather conditions. The system has various view modes and can track with FLIR or by TV. The same system is also used on the UH-1Y Venom
UH-1Y Venom
The Bell UH-1Y Venom is a twin-engine medium size utility helicopter, part of the United States Marine Corps' H-1 upgrade program. The helicopter is also called Yankee for its variant letter....
and the KC-130J Harvest HAWK.
Operational history
The AH-1Z completed sea-trial flight testing in May 2005. On 15 October 2005, the USMC, through the Naval Air Systems Command, accepted delivery of the first AH-1Z production helicopter to enter the fleet. The AH-1Z and UH-1Y completed their developmental testing in early 2006. During the first quarter of 2006 the aircraft were transferred to the Operational Test Unit at the NAS Patuxent River, where they began operational evaluation (OPEVAL) testing.In February 2008, the AH-1Z and UH-1Y began the second and final portion of OPEVAL testing. AH-1Z testing was stopped in 2008 due to issues with its targeting systems. The AH-1Z was finally declared combat-ready in September 2010.
Operators
- United States Marine CorpsUnited States Marine CorpsThe United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...
has received all AH-1Zs from its order of 28 as of January 2011.
Specifications (AH-1Z)
See also
External links
- AH-1Z page on Bell Helicopter Textron web site
- AH-1Z Viper page on US Navy RDA site
- AH-1Z page on GlobalSecurity.org
- Bell AH-1Z Super Cobra – Bell 449 on helis.com
- H-1 Upgrade Program (UH-1Y/AH-1Z), U.S. Marine Corps, 2007.
- "First Production H-1 Helicopters Rollout", Bell Helicopter, 27 September 2006
- " AH-1Z Super Cobra Completes Envelope Expansion Testing", U.S. Navy, 9 January 2003.