<text><span class="style10">ircraft (8 of 12)1. Development</span><span class="style7">During the 1920s and 1930s large multi-engined flying boats were widely used for long-distance over-water services, but they rapidly declined with the development of long-range land planes just before and during World War II.</span></text>
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<text><span class="style10">he Vought-Sikorsky VS-300</span><span class="style7">, seen here piloted by designer Igor Sikorsky, was the first successful American helicopter. It made its maiden flight on 13 May 1940.</span></text>