The Bell Huey family of helicopters includes a wide range of civil and military aircraft produced since 1956 by Bell Helicopter. This H-1 family of aircraft includes the utility UH-1 Iroquois and the derivative AH-1 Cobra attack helicopter series and ranges from the XH-40 prototype, first flown in October 1956 to the 21st-century UH-1Y Venom and AH-1Z Viper. Although not flown in military service in the USA, the Bell 412 served in Canada and Japan, and like the UH-1Y is a twin engine four rotor design based on the Bell 212.

The H-1 upgrade program is the United States Marine Corps's program to develop the AH-1Z Viper and UH-1Y Venom military helicopters to replace its aging fleets of AH-1W SuperCobras and UH-1N Twin Hueys. The contract was awarded in 1996 to Bell Helicopter, the original manufacturer of both aircraft, to design the new airframes as modernized attack and utility helicopters with considerable design commonality, to reduce operating costs.