The Bell AH-1Z Viper is a modern version of the AH-1 Cobra, the first ever attack helicopter. The modern version is also called Zulu Cobra in reference to its variant letter. Since its introduction in the mid-1960s, the original Cobra has been constantly improved and upgraded. The latest AH-1Z Viper is a result of the H-1 helicopter upgrade program for the US Marine Corps, which was launched by the US Government in 1996. The Bell helicopter company was eventually awarded a contract to deliver both upgraded and newly built AH-1Z Vipers to the US Marine Corps. The Viper gunship was developed alongside the UH-1Y Venom utility helicopter under the same program.

The AH-1Z Viper is a direct derivative of the AH-1W Super Cobra. It is one of the most powerful, capable and advanced helicopters, flying today. The AH-1Z made its first flight back in 2000. It was introduced to the US Marine Corps in 2010. Full-scale production commenced in 2012. Marines plan to receive a total of 189 Vipers until 2019. These include 131 AH-1W upgraded into AH-1Z and 58 newly built AH-1Z helicopters. In 2015 it was announced that 12 of these gunships will be delivered to Pakistan.

Upgrades of the AH-1Z included the implementation of state-of-the-art weapons and digital technology to respond to modern demands for contemporary warfare. The Viper features outstanding flying and combat capabilities.

The AH-1Z has essential changes in propulsion. It is powered by two General Electric T700-GE-401C turboshaft engines and has an uprated transmission. One of the main external differences from the AH-1W is a composite 4-bladed main rotor, instead of the previous 2-bladed rotor. It reduced vibrations by up to 70 percent. It is worth noting that a 2-bladed rotor was a distinctive feature of all previous Bell helicopter models. However, due to these changes flying characteristics improved a lot.

Despite all improvements and upgrades appearance of the AH-1Z remains the same. The pilot is seated at the rear and the co-pilot/gunner at the front. The layout of two integrated digital cockpits is identical and all systems are duplicated.

This helicopter uses off-the-shelf electronic systems. It can operate during the day, at night, or under adverse weather conditions. It has night vision twinned with infrared and new target search and acquisition software. It permits Viper to find and engage targets at long range. It can be fitted with Longbow fire control radar, mounted on a wingtip station. Also, there is an automatic flight control station.

The armament of the Viper is very flexible. It is enhanced by helmet-mounted sight and display system. The AH-1Z carries about 2 t of various ωɛλρσɳs on stub-wings. Typically it carries AGM-114A/B/C Hellfire anti-tank missiles (up to 16) and pods with 70 mm unguided rockets. The Viper can be also fitted with AGM-114F Hellfire anti-ship missiles, and free-fall bombs, including the Mk.77 incendiary bombs. It can also carry two fire-and-forget AIM-9 Sidewinder short-range air-to-air missiles. These a mounted on wingtip stations. Also, there is a 20 mm three-barrel cannon.

A number of improvements were made to the survivability and crashworthiness of the helicopter. It is fitted with an infrared suppression system that covers engine exhausts, laser and radar warning systems, and a radar jammer. It also has smart countermeasures dispenser with a missile warning device.

The latest airframe technologies were implemented, such as crash-worthy seats, energy-absorbing landing gear, self-sealing fuel tanks and fuel systems, and fuel vapor inerting systems.

The fuselage of the helicopter and external components were coated to avoid corrosion during prolonged service at sea. These helicopters typically operate from amphibious assault ships.