1947: Spruce Goose flies

History.com has this for today:

The Hughes Flying Boat (video), the largest aircraft ever built, is piloted by designer Howard Hughes on its first and only flight. Built with laminated birch and spruce, the massive wooden aircraft had a wingspan longer than a football field and was designed to carry more than seven hundred men to battle.
Howard Hughes was a successful Hollywood movie producer when he founded the Hughes Aircraft Company in 1932. He personally tested cutting-edge aircraft of his own design and, in 1937, broke the transcontinental flight-time record. In 1938, he flew around the world in a record three days, nineteen hours, and fourteen minutes.
Following the US entrance into World War Two in 1941, the American government commissioned the Hughes Aircraft Company to build a large flying boat capable of carrying men and materials over long distances. The concept for what would become the Spruce Goose was originally conceived by the industrialist Henry Kaiser, but Kaiser dropped out of the project early, leaving Hughes and his small team to make the H-4 a reality. Because of wartime restrictions on steel, Hughes decided to build his aircraft out of wood, laminated with plastic and covered with fabric. Although it was constructed mainly of birch, the use of spruce (along with its white-gray color) would later earn the aircraft the nickname Spruce Goose. It had a wingspan of three hundred and twenty feet and was powered by eight giant propeller engines.
Development of the Spruce Goose cost a phenomenal twenty-three million dollars and took so long that the war had ended by the time of its completion in 1946. The aircraft had many detractors, and Congress demanded that Hughes prove the plane airworthy. On 2 November 1947, Hughes obliged, taking the H-4 prototype out into the harbor at Long Beach, California for an unannounced flight test. Thousands of onlookers had come to watch the aircraft taxi on the water and were surprised when Hughes lifted his wooden behemoth seventy feet above the water and flew for a mile before landing.
Despite its successful maiden flight, the Spruce Goose never went into production, primarily because critics alleged that its wooden framework was insufficient to support its weight during long flights. Nevertheless, Howard Hughes, who became increasingly eccentric and withdrawn after 1950, refused to neglect what he saw as his greatest achievement in the aviation field. From 1947 until his death in 1976, he kept the Spruce Goose prototype ready for flight in an enormous, climate-controlled hangar at a cost of a million dollars per year. Today, the Spruce Goose is housed at the Evergreen Aviation Museum in McMinnville, Oregon.