ABOUT THE COVER: This month marks the 100th anniversary of powered flight. To commemorate the past and look toward future achievements in aerospace, the cover of this issue is an artist’s representation of powered flight. In the upper left corner is an early conception of manned flight: a flying machine sketched by Leonardo da Vinci. The abstract cityscape represents the technological explosion of the past 100 years. The spiraling timeline signifies aerospace milestones, starting with the Wright Brothers’ 1903 flight and leading to today’s advanced generation of aerospace products. The child represents the future contributions to aerospace that will be designed in forthcoming generations.