First designated HK- I, later changed to H-4 when Henry Kaiser withdrew from the project, The Hughes Flying Boat is commonly called the "Spruce Goose". The aircraft is a cargo-type flying boat
designed to transport men and materials over long distances. Originally conceived by Henry Kaiser (famous for the production of liberty ships) the aircraft
was designed and constructed by Howard Hughes and his staff . The Hughes Flying Boat is of a single hull
design, with a single vertical tail
, fixed wing-tip floats, and full cantilever wing
and tail surfaces. The entire airframe
and surface structures are composed of laminated wood
(primarily birch). All primary control surfaces except the flaps are fabric covered. The "Spruce Goose" hull is divided into two areas: a flight deck for the operating crew and a large cargo deck. Access between the two decks
is provided bv a circular stairway. Below the cargo deck are fuel
bays divided by watertight bulkheads.
It was born of a critical national need to fly over the enemy submarines ravaging shipping lanes during World War II. First designated the HK-1 for the Howard Hughes and Henry Kaiser venture that responded to the government requirement, it was later called the H-4 Hercules.
The Hughes Flying Boat was to be the biggest airplane ever built and probably the most prodigious aviation project of all time. Only the courage and solitary dedication of Howard Hughes and his small development group caused this project to advance what a disgruntled U.S Senator dubbed the "flying lumberyard" resulting in its historic flight in November 1947.
Wingspan: 319.92' (97.54m)
Fuselage: 219' (66-75m)
Vertical Tailspan: 49.5'
Gross Weight: Approx. 400,000 lbs. (181,440 kg.)
Fuselage Height: Approx. 30' (9.14m.)
Design Cruising Speed: Approx. 200 mph (322kml/h)
Landing Speed at Sea Level: 10% above stall with 45' flap 81 to 87 mph.
Maximum Range: Approx. 3,000 miles
Endurance in Hours at Best Cruising Speed: 20.9 hrs.
Maximum Service Ceiling: 20,900 ft.
Maximum Rate of Climb at Sea Level: Approx. 1,000 ft/min
Engines: 8 Pratt and Whitney R-4360's rated at 3,000 h.p. each. Largest radial reciprocating engines ever built.
Propellers: 8 four-bladed Hamilton Standards, diameter 17' 2". The four inboard propellers have reverse pitch capability.