For two days in mid-July, 100 miles off the northern coast of Oahu in Hawaii, the U.S. Navy aircraft carrier USS Nimitz played host to the first large-scale demonstration of the Navy's Great Green Fleet. More than 70 aircraft, including F/A-18 Hornet fighter jets, E-2 Hawkeye early warning aircraft, and helicopters, as well as destroyers and other ships, participated in the biannual Rim of the Pacific naval exercises with sailors and pilots from 21 other nations. A 50-50 biofuel/petroleum blend powered virtually all of the Navy's ships and aircraft.