National Air and Space Museum curator Bob van der Linden looks at the history of the flying boat, and how infrastructure investments during World War II changed commercial aviation.
Boeing Model 314 Clipper "Atlantic Clipper"Original Source: National Air and Space Museum Archives, Smithsonian Institution
In the late 1930s, Pan American Airways opened air travel across the Atlantic and Pacific Oceans. Earlier, Juan Trippe’s legendary airline blazed new routes from the United States throughout Latin America. With Charles Lindbergh as his friend and technical advisor, Trippe developed a series of magnificent flying ocean liners from Sikorsky, Consolidated, Martin, and Boeing. These graceful flying boats flew air mail, businessmen, and the extremely wealthy to romantic spots around the globe.
Pan Am’s Sikorsky S-42s and Consolidated Commodores plied the airways around the coast of South America, connecting Miami with cities like Caracas, Rio de Janeiro, and Buenos Aires. In the Pacific, the legendary Martin M-130 “China Clipper” began passenger service to the Far East in 1936, opening Hawaii, the Philippines, and Hong Kong to adventurous travelers. By 1939, Pan American flew directly from New York to Europe in the magnificent Boeing 314.
Other nations opened the world to air travel using flying boats, such as Great Britain, with the beautiful Shorts C-class, and France, with the graceful Latécoère series, connecting the cities of Europe to their colonies in Africa, the Middle East, and Asia.
Marine Air TerminalOriginal Source: National Air and Space Museum Archives, Smithsonian Institution
For long distance overseas flight, the flying boat was the obvious solution. As most of the world’s major cities lie along coastlines and have port facilities, expensive conventional airfields were not necessary. Furthermore, large flying boats required long takeoff distances. With the open water, flying boasts had unlimited distances in which to get airborne. As a result, by 1939 flying boats dominated long distance international air travel.
And then they were gone.
Aviation technology advanced by leaps and bounds during the 1930s. Despite the Great Depression, new breakthroughs in design, materials, and construction brought a new generation of all metal airliners, capable of dramatic improvements in range, speed, and capacity than the wood and fabric machines of an earlier time. With more powerful engines, aircraft grew dramatically in size and weight. Unfortunately, the landing fields of most existing airports were either open grass or made from compacted gravel. As late as 1938, the only concrete runway in the U.S. was at Floyd Bennett Field on Long Island, New York. The first generation of modern twin-engine airliners such as the Boeing 247, the Douglas DC-2, and DC-3s could handle these fields, but the next generation of four-engine airliners would be too heavy.
Runway ConstructionOriginal Source: National Archives and Records Administration
Towards the end of the 1930s, the aviation industry was reluctant to confront this problem. Building hard surface concrete runways was the solution to the problem but pouring new runways at airports across the country and around the world was prohibitively expensive.
World War II changed that. The pressing needs of the military outweighed peacetime cost concerns as the nation needed to move people, materiel, and supplies around the world as fast as possible in order to confront the Axis enemy and reinforce our Allies. Wherever America’s forces went, hard runways of concrete and asphalt followed. In the Pacific, the U.S. Navy’s famous “Sea Bees,” construction battalions, paved over countless islands on their relentless drive to Japan. The U.S. Army Corps of Engineers and engineer aviation battalions built hardened runways all over Great Britain, Europe, and across the North Atlantic. Working with Pan American, the Army built airports with concrete runways across the Caribbean, across the northern part of South America, across the South Atlantic, and across north and central Africa to the Middle East and on towards India to bases in China. Domestically, the military built hundreds of new airports while the government upgraded and paved existing municipals airfields.
Douglas C-54EOriginal Source: National Archives and Records Administration
During the war, newer, larger aircraft, fitted with tri-cycle landing gear, rather than the traditional “tail dragger” designs, appeared in great numbers. The United States produced thousands of four-engine Boeing B-29 bombers and Douglas DC-4s and Lockheed Constellation transports that were too heavy for grass or gravel. With hundreds of new concrete and asphalt runways constructed around the globe, these latest bombers and transports could now fly virtually anywhere, unrestricted by grass field and inadequate facilities. Immediately after the war in 1945, the DC-4, and its pressurized big brother, the DC-6, and the Lockheed Constellation and Super Constellation came to dominate international air travel.
Douglas DC-4Original Source: National Air and Space Museum Archives, Smithsonian Institution
And flying boats were then forgotten. With adequate runways the world over, there was little need for the bulky, inefficient flying boat with its high-drag fuselage. Some remained in service, but only on limited niche routes operated by secondary airlines. By 1951 the last of the Boeing 314s sank beneath the waters of Baltimore harbor. The age of the flying boat was over.
Author: Bob van der Linden, curator, Smithsonian National Air and Space Museum
