Into Stability

Gregory W. Evans is an engineer, author, and historian whose work bridges technology, family legacy, and the human side of invention. A graduate of Caltech (B.S. 1969) and Stanford (M.S. 1975), Evans spent his career at the intersection of aerospace systems and defense electronics. His latest book, Into Stability: Walter R. Evans and the Story of Root Locus, celebrates the life and legacy of his father, Walter R. Evans-the engineer whose Root Locus Method transformed control-system design and became a cornerstone of modern engineering education. Drawing from decades of correspondence, laboratory reports, and family archives, Evans reconstructs the mid-century world of North American Aviation's Aerophysics Laboratory, where the foundations of modern feedback control were laid. Beyond chronicling a pivotal technical innovation, his earlier works include family and migration histories tracing his ancestors from Wales and England to the American Midwest, combining rigorous research with a storyteller's touch. Evans lives in California, where he continues to write, photograph, and preserve the stories of innovation that shaped both his family and his field.