The Bell (model 206A) OH-58A Kiowa was procured by the U. S. Army when the Light Observation Helicopter (LOH) program was reopened for an additional buy in March 1968. The OH-58A was first deployed to Vietnam in early Autumn 1969. The Kiowa operated with air cavalry, attack helicopter, and field artillery units. The OH-58A could also be configured as a troop transport, MedEvac, or for external lift missions using an external hook. Kiowas were commonly paired with the AH-1G "Huey" Cobra. The Kiowa would fly low to draw enemy fire, "trolling" for fire, mark the target, and call in the Cobra to attack. The OH-58A Kiowa could be armed with the M27 armament subsystem, the port (left) side mounting M134 six-barrel 7.62mm "Minigun". However the vibration from the "minigun" was too great for the frame until it was rebuilt for the OH-58D Kiowa Warrior. The Kiowa could also be armed with the 40mm grenade launcher on the XM8 armament subsystem. The Kiowa had a two-bladed semi-rigid seesaw all metal main rotor and a two-bladed rigid delta hinge all metal tail rotor. The OH-58A was powered by a single Allison 250-C18 317 shp turbine engine and has a speed of 132 mph (115 knots).