The Legend of the Spruce Goose: It Flew Once (and We Still Talk about It)
The Time magazine article was titled “It Flies!” It was a note of triumph and vindication, but also an epitaph, of an aircraft that was five years in the making—the “Spruce Goose,” a plane that should not have existed. Many things were against it, even, to a certain degree, its creator.
The week of May 4-10, 1942, saw the loss of 300,000 deadweight tons of Allied shipping to German U-boats, loss rates that were twice new ship launches. Imaginative use of America’s industrial and technological strengths to deal with such problems was the mission of the War Production Board’s planning committee.
On May 22, F.H. Hoge, Jr., a member of the committee, proposed the use of extremely large flying boats, pointing out that current aircraft on transoceanic flights devoted 38 percent of their takeoff weight to fuel and oil, but that a 300,000-pound plane would use only 20 percent, and, that since flying boats did not require landing gear, an additional 15 percent in aircraft weight would be saved.
But it was the industrialist Henry J. Kaiser who saw the opportunity. He approached such problems with big schemes, limitless energy, and a genius for organization and improvisation. He had moved from constructing mammoth hydroelectric dams, such as the Hoover and Grand Coulee, to shipbuilding in 1941.
Faced with the terrible loss of shipping that was threatening the Allies, Kaiser suggested two possible solutions. One was to convert some of his shipyards to the mass production of giant seaplanes. The other was to mass produce antisubmarine aircraft carriers on Liberty Ship hulls. In the latter case, Kaiser facilities would produce some 70 escort carriers during the war.
But in the summer of 1942, after the Germans sank 681 Allied ships in the first seven months of the year, the idea of flying boats captured the nation’s imagination. In July, Kaiser outlined plans for flying boats of 200 to 500 tons and launched a publicity and lobbying campaign telling the press that he envisioned a fleet of 5,000 flying boats.
He followed with a proposal to the Army and Navy. And, though they considered it impractical, they knew that the public and some members of Congress believed otherwise. The Aircraft Division of the War Production Board was asked to review Kaiser’s proposal.
Merrill C. Meigs, deputy director of the board’s Aircraft Division, told Kaiser that it took more than four years to develop a new aircraft, but Kaiser was undaunted. Regarding possible resource requirements, Kaiser said he would build a steel foundry and educate and develop technicians and engineers in support of his proposal.
Meigs then set up a committee of aircraft manufacturers to hear Kaiser’s plans. But the manufacturers were not enthusiastic about the possible entry of another aircraft company into their industry. Donald Douglas, head of Douglas Aircraft, advised that to prepare a preliminary design for a 200-ton aircraft would require at least 100,000 engineering hours.
During July and August, Kaiser made two proposals—mass production of the Martin Mars flying boat and the design and development of the 200-ton flying boat––both taken under consideration by the War Production Board, headed by Donald Nelson. The Mars, first flown in June 1942, was a four-engine, 200-foot wingspan, 75,000-pound aircraft capable of carrying a 32,000-pound payload, or 133 troops, over a range of 5,000 miles. But Nelson was concerned about the possible impact on existing programs by manufacturers working at full capacity.
Kaiser then approached the well-known aviator, Howard Hughes, with a pitch to jointly develop the large flying boat. Though aware of the problems in designing a new aircraft, Hughes was intrigued with the possibility of coming up with the world’s largest airplane, especially after being told that the Douglas, Martin, and Northrup aircraft companies all thought that it couldn’t be done.
By August 22, 1942, after several weeks of discussion, a handshake agreement was reached—Hughes would design the plane and Kaiser would build it. Subsequently, a written contract between Hughes and Kaiser called for the design and construction of 500 aircraft.
The Gigantic Spruce Goose
On September 17, Kaiser-Hughes received authorization to proceed with design engineering and construction of three prototype flying boats. Among the conditions imposed were that all construction would use a minimum of any critical or strategic materials, that no engineers or technicians working for manufacturers already engaged in the war effort could be employed without the permission of their employers, that they could spend no more than $18 million, and that the program would be limited to 24 months. But the Kaiser-Hughes partnership soon dissolved and Hughes proceeded alone. During the first seven months of the project, Hughes acted as general manager. Kaiser, unsuccessful in his attempt at combining forces with Hughes, had nothing more to do with the project except to help out with providing a few personnel.
Design presented several challenges—such a plane would require an overhang wingspan 50 percent greater than the Martin Mars, which would present new torsional, wing flutter, vibration, deflection, and control problems never before tested.
Seven aircraft configurations were drawn up, including twin-hull and single-hull designs with four to eight engines. Hughes settled on a design gross weight of 400,000 pounds. This number was reached based on creating the largest aircraft possible using eight of the largest engines then under development. Eight was considered the maximum number of engines that seemed practical.