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Hughes H4 Hercules ‘Spruce Goose’

Hughes H4 Hercules ‘Spruce Goose’   During WWII, U boat raids in the Atlantic were causing heavy losses of shipping, many of which were carrying war supplies to the Allies in Europe and beyond. In 1942 the US War Department issued a specification for an aircraft capable of flying the Atlantic with a large payload. No strategic materials were available for the construction of the plane. The design was the brainchild of Howard Hughes and Henry Kaiser (a leading Liberty ship builder and an expert in the use of plywood in construction).

Originally described as the HK 1 reflecting the collaboration between the two men, the specification required the building of three aircraft in two years. Because there was no aluminium available the plane was constructed largely of birch ply. It was to be capable of carrying 150,000 lb (68039 kg): 750 fully equipped troops, or two 30 ton Sherman tanks.

Development was extremely slow, in part due to Howard Hughes’ obsession with perfection and his attempts to acquire strategic materials. After 16 months Kaiser withdrew from the project.

Hughes renegotiated the contract so that only one plane was to be built. Now designated Hughes H 4, progress was slow. The ‘Duramold’ process (a plywood and resin process of cold moulding plywood) was used. The specialised veneer was made by Roddis Manufacturing.

Due to the slow rate of progress; Howard Hughes was accused of misusing Government money. During the court hearing Hughes stated that the plane was extremely complex, larger than any other airplane (until 2019), complicated in the use of plywood and the requirement to develop hydraulics for surface controls. the list went on…

During a break in the court hearing Hughes returned to California to run the taxiing tests.

Initially there were 36 people on board. Four press reporters left after the first two runs to file their reports. During the final run the plane became airborne at 135 mph (217 kph), flew at 70 ft (21 m) for about 1 mile (1.6 km).

Thus Hughes exposed his detractors; his masterpiece flew, he had not misused Government funds.

Spruce Goose never flew again. It was stored in an air conditioned hanger with a staff of 300  to maintain it in ‘flying’ condition. This was reduced to 50 in 1962 and ceased completely at Hughes’ death in 1976.

The Aero Club of Southern California acquired Spruce Goose in 1980. The Walt Disney Company acquired the plane in 1988 parting with it in 1990 when it became part of the Evergreen Aviation Museum. 

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