The Hughes H-4 Hercules, famously nicknamed the Spruce Goose, remains the largest flying boat ever constructed. Its massive wingspan stretches 320 feet, surpassing the length of many football pitches, which typically measure between 300 and 390 feet.
Design and Intended Purpose
Engineers at Hughes Aircraft Company, led by aviation pioneer Howard Hughes, designed this prototype for transatlantic transport during World War II. The aircraft aimed to carry up to 750 troops or heavy cargo like two Sherman tanks across the ocean.
Constructed primarily from laminated birch wood, the Spruce Goose boasts an empty weight of nearly 113,400 kg and a fuselage exceeding 218 feet. Eight powerful engines, each equipped with 17-foot-diameter four-bladed propellers—four on each side—provided the thrust for this colossal machine.
The Historic Single Flight
The project missed its wartime deadline, so the prototype never served in combat. Howard Hughes piloted its sole flight on November 2, 1947, from Long Beach Harbor in California. The flying boat lifted off, soared about 70 feet above the water for roughly 26 seconds, and covered approximately one mile before splashing down.
Legacy and Display
Despite its brief flight, the Spruce Goose never advanced beyond the prototype phase and became an aviation legend. Today, visitors to the Evergreen Aviation & Space Museum in McMinnville, Oregon, can experience its immense scale firsthand.
For decades, it held the record for the widest wingspan until the Stratolaunch jet’s 385-foot span claimed the title in 2019.
