Exercise Red Flag is an aerial combat training exercise of the US armed forces. It is held at Nellis Air Force Base at Nevada. The Red Flag – Alaska is conducted at the Eielson Air Force Base. This is a successor to the COPE THUNDER exercises which were held in Alaska and the Western Pacific. Conducted since 1975, the exercise draws air crew from the US Air Force, US Navy, US Army, US Marine Corps, and several NATO and/or allied countries’ air forces. The exercise is held once annually and each exercise lasts for 2 weeks.