In the decades since the Wright brothers' first flights, a body of knowledge and tools, created in an evolutionary process of small steps, had been built up to guide engineers and researchers in developing new aircraft. The early wood-and-fabric biplanes had given way to all-metal monoplanes. Aircraft size, range, and payload had also grown, until the oceans could be spanned in a fraction of the time a ship would take. Speed became the critical factor in both commercial and military operations.
Curtis Peebles
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