Vertibirds are Enclave helicopter vehicles used as scouts and troop transports. In 2241 one of them crashed near the trapper town of Klamath, and was the first sign of the Enclave encountered by the Chosen One. In 2277, they are still used by the Enclave in the Capital Wasteland area. The Vertibird is a lateral twin-rotor (non-synchronized) helicopter design. An actual experimental prototype for this type of aircraft was the Platt-LePage XR-1/XR-1A tested by the US Army in the 1940's. Others included the German Fa 223 and the McDonnell XHJD-1 "Whirlaway".