AH-1Z Viper
From Wikipedia, the free encyclopedia
| AH-1Z Viper | |
|---|---|
 An USMC AH-1Z "Viper" undergoing testing at NAS Patuxent River |
|
| Type | Attack helicopter |
| Manufacturer | Bell Helicopter |
| Maiden flight | December 8, 2000 |
| Introduction | 2009 |
| Status | In development |
| Primary user | United States Marine Corps |
| Developed from | AH-1 SuperCobra |
The Bell AH-1Z Viper (also called "SuperCobra") is an American 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.[1]
Contents |
[edit] Development
Aspects of the AH-1Z dates back to the Bell 249 in 1979, which was basically an AH-1S equipped with the four-blade rotor system from the Bell 412. This helicopter demonstrated Bell's Cobra II design at the Farnborough Air Show 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 TOWs, 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.[2]
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 (upgrading 100 UH-1Ns into UH-1Ys was also included).[2][3] 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.[4]
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.[2] The existing two-bladed semi-rigid, teetering rotor system is being replaced with a four-bladed, hingeless, bearingless rotor system. The improvement in flight characteristics provided by the four-bladed configuration has led to increases in flight envelope, maximum speed, vertical rate-of-climb, payload and rotor vibration level.[5]
The AH-1Z first flew on December 8, 2000.[6] Three prototype aircraft were delivered to NAVAIR's Naval Air Station Patuxent River in July 2002 for the flight test phase of the program. Low-rate initial production followed beginning in October 2003,[2] with deliveries to run through 2018.[7] On October 15, 2005, the USMC, through the Naval Air Systems Command, accepted delivery of the first AH-1Z production helicopter to enter the fleet.[8]
The AH-1Z completed sea-trial flight testing in May 2005.[9] 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.[10] In February 2008, the AH-1Z and UH-1Y began the second and final portion of OPEVAL testing.[11]
Bell delivered a UH-1Y to the U.S. Marine Corps on February 26, 2008, for February's third H-1 Upgrade delivery. The previous February deliveries were an AH-1Z on February 8, and an UH-1Y on February 13. A full-rate production decision is expected later this year.[1]
[edit] Design
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.[4]
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 ships.[4] 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 70 mm (2.75 in) Hydra 70 rocket pods, or AGM-114 Hellfire quad missile launchers. The Longbow radar can also be mounted on a wing tip station.[2]
The Z-model's integrated avionics system (IAS) has been developed by Northrop Grumman. The system include two mission computers and an automatic flight control system. Each crew station has two 8x6-inch multifunction liquid crystal displays (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.[5]
The crew are equipped with the Thales "Top Owl" helmet-mounted sight and display system.[1] 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 Infared Suppression System (HIRSS) to cover engine exhausts, countermeasure dispensers, radar warning, missile warning and laser warning systems.[4]
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.[4]
[edit] Operators
- United States Marine Corps (180 on Order)
[edit] Specifications
Data from Bell Specifications,[4] The International Directory of Military Aircraft, 2002-2003,[12] Modern Battlefield Warplanes[2]
General characteristics
- Crew: 2: pilot, CPG (co-pilot/gunner)
- Capacity: 6,661 lb (3,021 kg)
- Length: 58 ft 3 in (17.8 m)
- Rotor diameter: 48 ft (14.6 m)
- Height: 14 ft 4 in (4.37 m)
- Disc area: 1,808 ft² (168.0 m²)
- Empty weight: 12,300 lb (5,580 kg)
- Useful load: 5,764 lb (2,620 kg)
- Max takeoff weight: 18,500 lb (8,390 kg)
- Powerplant: 2× General Electric T700-GE-401C turboshaft, 1,800 shp (1,340 kW) each
- Rotor systems: 4 blades on main rotor, 4 blades on tail rotor
Performance
- Never exceed speed: 222 knots (255 mph, 411 km/h)
- Maximum speed: 160 kn (184 mph, 296 km/h)
- Cruise speed: 134 kn (150 mph, 248 km/h)
- Range: 370 nmi (426 mi, 685 km)
- Combat radius: 110 nmi (127 mi, 204 km)
- Service ceiling 20,000+ ft (6,100+ m)
- Rate of climb: 2,790 ft/min (14.2 m/s)
Armament
- M197 3-barreled 20 mm "Gatling-style" cannon in the A/A49E-7 turret (750 rounds ammo capacity)
- 2.75 in (70 mm) Hydra 70 rockets - Mounted in LAU-68C/A (7 shot) or LAU-61D/A (19 shot) launchers
- AGM-114 Hellfire Missiles - Up to 8 missiles mounted in two 4-round M272 missile launchers, one on each outboard hardpoint
- AIM-9 Sidewinder Anti-Aircraft Missiles - 1 mounted on each wing tip station (total of 2)
[edit] See also
Related development
Comparable aircraft
Related lists
[edit] References
- ^ a b Bell AH-1Z page, Bell Helicopter, Retrieved 3 January 2008.
- ^ a b c d e f Donald, David. Modern Battlefield Warplanes. AIRTime Publishing, 2004. ISBN 1-880588-76-5.
- ^ Bishop, Chris. Huey Cobra Gunships. Osprey Publishing, 2006. ISBN 1-84176-984-3.
- ^ a b c d e f Bell AH-1Z Pocket Guide, Bell Helicopter, Retrieved 3 January 2008.
- ^ a b AH-1W/AH-1Z Super Cobra Attack Helicopter, USA, Airforce-Technology.com. Retrieved January 14, 2008.
- ^ "AH-1Z completes first flight", Bell Helicopter, December 7, 2000.
- ^ "AH-1Z/UH-1Y complete developmental testing", US Navy, March 6, 2006.
- ^ "Bell 449 SuperCobra and KingCobra", Jane's Information Group, 7 December 2005.
- ^ "AH-1Z/UH-1Y complete first sea trials", US Navy, June 13, 2005.
- ^ "AH-1Z/UH-1Y Start OPEVAL", US Navy, May 6, 2006.
- ^ Warwick, Graham. "US Marine Corps' Bell AH-1Z and UH-1Y enter final test phase", Flightglobal.com, 20 February 2008.
- ^ Frawley, Gerard: The International Directory of Military Aircraft, page 37. Aerospace Publications Pty Ltd, 2002. ISBN 1-875671-55-2.
[edit] External links
- AH-1Z page on Bell Helicopter Textron web site
- AH-1Z Viper page on US Navy RDA site
- AH-1Z / UH-1Y on U.S. Navy PMA-276 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, September 27, 2006
- "New H-1s reach 3,000 hrs, prep for OpEval", U.S. Marine Corps, June 13, 2005.
- " AH-1Z Super Cobra Completes Envelope Expansion Testing", U.S. Navy, January 9, 2003.
|
||||||||
|
||||||||
|
||||||||||||||
