Intended as a transatlantic flight transport for use during World War II, it was not completed in time to be used in the war. The aircraft made only one brief flight on November 2, 1947, and the project never advanced beyond the single example produced. Built from wood because of wartime restrictions on the use of aluminum and concerns about weight, the aircraft was nicknamed the Spruce Goose by critics, although it was made almost entirely of birch. The Hercules is the largest flying boat ever built, and it had the largest wingspan of any aircraft that had ever flown until the Scaled Composites Stratolaunch first flew on April 13, 2019. The aircraft remains in good condition. After having been displayed to the public in Long Beach, California, from 1980 to 1991, it is now on display at the Evergreen Aviation & Space Museum in McMinnville, Oregon, United States. In 1942, the U.S. War Department needed to transport war materiel and personnel to Britain. Allied shipping in the Atlantic Ocean was suffering heavy losses to German U-boats, so a requirement was issued for an aircraft that could cross the Atlantic with a large payload. Wartime priorities meant the aircraft could not be made of strategic materials (e.g., aluminum). The aircraft was the brainchild of Henry J. Kaiser, a leading Liberty ship builder and manufacturer. Kaiser teamed with aircraft designer Howard Hughes to create what would become the largest aircraft yet built. It was designed to carry 150,000 pounds (68,000 kg), 750 fully equipped troops or two 30-ton M4 Sherman tanks. The original designation "HK-1" reflected the Hughes and Kaiser collaboration. The HK-1 aircraft contract was issued in 1942 as a development contract and called for three aircraft to be constructed in two years for the war effort. Seven configurations were considered, including twin-hull and single-hull designs with combinations of four, six, and eight wing-mounted engines. The final design chosen was a behemoth, eclipsing any large transport then built. It would be built mostly of wood to conserve metal (its elevators and rudder were fabric-covered), and was nicknamed the Spruce Goose (a name Hughes disliked) or the Flying Lumberyard. For more information on this unique aircraft, click here.
