 The AH-1 Cobra arrived in 1967 to partially replace the Huey in its gun ship capacity.Other important helicopters in Vietnam included the Boeing CH-47 Chinook, the Hughes OH-6 Cayuse, the Bell OH-58 Kiowa, and the Sikorsky CH-54 Tarhe.Although the concept of air mobility had been developed with a mid-intensity European conflict in mind, Army Aviation and the helicopter had proven themselves during the low intensity conflict in Southeast Asia.