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 as part of the H-1 upgrade program.
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 (USMC). The AH-1Z is part of the H-1 upgrade program.