Some of the most significant engineering and technological breakthroughs of the 20th century centered on the development of piston aero engines from 1920 to 1957. This book explains in detailed, well-illustrated, and easy-to-understand terms how these piston-powered radial-engine airliners advanced rapidly. The aircraft originated with fabric-covered fuselages with wooden wings and morphed into all-metal Ford Trimotors as the world's first true "modern...