The Bell AH-1Z is an American twin-engine attack helicopter, based on the AH-1W SuperCobra, which was developed for the United States Marine Corps as part of the H-1 upgrade program. The AH-1Z features four blades, no bearings, a composite main rotor system, an upgraded transmission, and a new target sighting system. [3] The AH-1Z, one of the newest members of the prolific Bell Huey family, is also called the Zulu Cobra, based on the military phonetic pronunciation of its letter variants.