Donald Windsor Stephenson, Sr. was born on January 22, 1925, in Lexington, Missouri. His parents were Patrick Charles Stephenson, Sr. and Florence Elsie Stephenson. His middle name was derived from his paternal grandmother's maiden name. He grew up in Lexington and attended its schools, graduating from Lexington High School in May 1943 as the salutatorian of his class. During high school, he participated in sports, playing two years of football and competing in track for four years. He was captain of the track team in his senior year. He had two brothers: an older brother, Patrick Charles Stephenson, Jr., and a younger brother, Meredith Franklin Stephenson.
In June 1943, shortly after graduating from high school, he was drafted into the Army during World War II and served until April 1946, when he was honorably discharged. His service included 15 months overseas in the India-Burma Theater of Operations. At the time of discharge, he held the rank of Technician, 4th Grade (Sergeant) and worked in communications in the Signal Corps. This included an assignment attached to the 20th Air Force (B-29s) in Kharagpur, India, for several months before the 20th Air Force moved to islands in the Pacific closer to Japan. The B-29s were the bombers involved in the atomic bombings in Japan.
Later, he assisted in maintaining a communications center at a small camp called Camp Burns, located between Calcutta and Barrackpore, India. After his Army discharge, Don enrolled at the University of Missouri, where he studied mechanical engineering, earning a bachelor's degree in June 1950 and a mastugust 1951. His grade point average enabled him to join two engineering honor societies: Pi Tau Sigma (mechanical engineering) and Tau Beta Pi (all engineering). He was also a member of the social fraternity Pi Kappa Alpha. President Harry Truman was the speaker at his bachelor's degree commencement.
In December 1947, he married Faye Sommerville of Lexington, Missouri. They had two children, Donald Windsor Stephenson Jr. and Jamie Ann Stephenson. Don and Faye divorced in October 1965 after almost 18 years of marriage. In December 1967, Don married Elaine Ann Ayers in Scottsdale, Arizona. She had two children from a previous marriage, Mark Steen Ayers and Christy Lynn Ayers. Don and Elaine had another child, Stacey Noel Stephenson, born in August 1969. Don and Elaine live in Gilbert, Arizona, and will celebrate 57 years of marriage in 2024. the aircraft's
In the spring of 1951, Don began working for the Trane Company in La Crosse, Wisconsin, as a sales engineer for aircraft heat exchangers. In 1954, he left Trane to join the Marley Company in Kansas City, Missouri, as a designer of industrial heat exchangers. The following year, he moved to Westinghouse in its Aviation Gas Turbine Division in Kansas City, Missouri, where he was employed as an engine performance engineer. When Westinghouse closed that division, he served as the Supervisor of the Engine Performance Group of Preliminary Design. He then began working for the Airesearch Division of Garrett Corporation in June 1960. Garrett later became part of Signal Corporation, then Allied-Signal, and is now integrated into Honeywell International. Initially, Don focused on performance and proposals primarily for auxiliary power gas turbine engines, but he later concentrated on engine performance as Garrett entered the main propulsion engine field. Upon his retirement in June 1992, he held the position of Manager of the Systems and Analysis Department of Allied-Signal, which included approximately 100 engineers, technicians, and support staff.