AH-1Z SUPERCOBRA
* The AH-1T that was modified to the AH-1T+ demonstrator and AH-1W prototype was later fitted with an advanced composite four-bladed rotor system that provided better performance, less noise, and greater resistance to battle damage. This "Four Bladed Whiskey (4BW)" Cobra didn't lead immediately to a production contract and the rotorcraft was returned to Marine service in a normal AH-1W configuration, but Bell continued development of the concept to come up with a new "AH-1Z" SuperCobra.
With the end of the Cold War, funds for buying new weapons dried up, and the US armed services increasingly had to make do with upgrade programs to bring their current weapons up to date. In 1996, the Marines signed a contract with Bell to upgrade 180 AH-1W SuperCobras to the AH-1Z standard.
The "Zulu Cobra" features a new, quieter four-blade composite rotor with an automatic folding mechanism to make the helicopter easy to store on ship, a 10,000-hour lifetime, and the ability to survive hits by 23 millimeter projectiles, as well as a new gearbox, transmission, and auxiliary power unit (APU). The new APU is the same as that used on the Sikorsky S-70 Black Hawk helicopter. A four-blade tail is also fitted. Fuel capacity is increased by 758 liters (200 US gallons), and the fuel tanks are filled with inert gas as they are emptied to reduce fire hazard.
The AH-1Z upgrade also increases stores capability to six wing stations, including two wingtip stations for missiles like the Sidewinder or Sidearm, and four for unguided rocket packs, or TOW or Hellfire quad missile launchers.
Cockpit and avionics are upgraded as well. The new cockpit features two multifunction 15 by 20 centimeter (6 by 8 inch) flat-panel displays for each crewman; secure radio communications; a tactical digital data system; a inertial-navigation system incorporating a GPS receiver; and a digital map display. Both sets of cockpit controls are largely identical, allowing either crewperson to fly the helicopter or fire its weapons. A rudimentary backup cockpit flight-control panel operated off battery power is also provided for each crewperson so that the AH-1Z can "limp home" if its AC power system is disabled.
The AH-1Z is fitted with a nose-mounted AN/AAQ-30 "Hawkeye" Target Sighting System (TSS), featuring a FLIR imager, low-level-light color zoom TV, a laser rangefinder, and an "eye-safe" laser target designator. The new FLIR imager is the key to the TSS. Earlier FLIRs didn't have the range to allow combat crews to identify a target from more than a few kilometers away, but the third-generation FLIR used in the TSS has large-aperture optics and an extremely effective stabilization system, allowing target identification from beyond the range of the Hellfire missile.
Zulu Cobra flightcrews will be fitted with advanced flight helmets developed by BAE Systems of the UK that are one of the core elements of the flight system. The helmet features a high-resolution projection TV system that can display flight or targeting data and imagery on the visor in a "see-through" fashion, and also can be fitted with snap-in cameras to provide a highly integrated night-vision capability. The helmet weighs only 2.2 kilograms (4.8 pounds) with the cameras in place.
Other system enhancements include a new self-defense suite, airborne target handoff system, an onboard systems monitor, two mission computers, and a mission data loader. The self-defense suite includes four ALE-47 chaff-flare dispensers that can be set to manual, semiautomatic, and fully automatic modes, along with an APR-39A radar warning receiver, an AVR-2 laser-warning unit, and and AAR-47 missile warning unit.
The AH-1Z is stretched to accommodate the new hardware and preserve its center of balance, and the airframe has been "zero-lifed". The upgraded SuperCobra carries 450 kilograms (1,000 pounds) more payload than the AH-1W, and cruises at 290 KPH (180 MPH), 40 KPH faster than the AH-1W. Combat radius for the AH-1Z is 200 kilometers (125 miles), while the combat radius of the AH-1W is only 70 kilometers (44 miles). The AH-1Z has a maximum takeoff weight of 8,390 kilograms (18,500 pounds), compared to 6,690 kilograms (14,750 pounds) for the AH-1W.
http://www.faqs.org/docs/air/avcobra.html