Obituary: John David Borthwick-Leslie, 1935-2022 

John David Alexander Borthwick-Leslie died peacefully after a long illness, at the age of 87, on August 26, 2022, in Shelburne, Vermont, surrounded by his family. The only child of Dr. Kathleen Borthwick and Dr. Walter Leslie, David was born in February 1935, in Fort Garry, Manitoba, Canada.

Raised for the most part by his mother, he attended boarding school while she was a major with the Canadian army during the Second World War. He graduated from Viscount Alexander High School in Fort Garry in 1952 and went on to graduate with a BS in engineering from the University of Manitoba in 1957. During college, he was an aerospace engineering officer with the Canadian Air Force.

After graduation, he relocated to Longueuil, Québec, to work for Pratt & Whitney Canada. He stayed with P&WC for 33 years, after starting as a junior engineer, helping to design and test aircraft engines. In 1971, he relocated his family to Wichita, Kan., where he inaugurated a branch office. In 1980, he lived in Cambridge, Mass., while completing the Harvard advanced management program. He became the manager of North American marketing before returning to Longueuil in 1981 as the director of airline support. When returning to work in Canada, he and his wife, Joyce, chose to buy 12 acres of lakeshore property in Grand Isle, Vt., where they designed and built a solar home. He retired from P&WC in 1990 then worked for five years in Fort Lauderdale, Fla., as a manager for Embraer. His final corporate job was with Atlantic Turbine Canada in Prince Edward Island from 1995 to 1999.

During his long career in the aviation industry, Dave traveled extensively internationally. He loved telling stories about his business and travel adventures in Europe, China and South America and made friends easily wherever he roamed.

He loved camping, hiking, and wandering with his wife and children through the Canadian and American Rockies and along both coasts of the continent — and everywhere in between. During scenic train rides, mountain jeep tours or other escapades, he could be found conversing with the guides and engineers. Learning and adventure were synonyms for Dave.

Even after beginning his semi-retirement, Dave could never slow down. His love of science, engineering, the outdoors, learning and his proclivity for forming friendships with every kind of human would compel him to action on his property, in his community and in the aircraft industry. Dave could spend the day clearing brush, building a stone staircase to the lake, tinkering with one of several forlorn European-make sports cars then go off to a town planning meeting. With the encouragement of his wife, Joyce, Dave became a member of multiple boards, committees and organizations, including  the Vermont Flight Academy, the Grand Isle Planning Commission, the Grand Isle Water District, the Grand Isle Development Review Board, the Friends of Northern Lake Champlain and the Northwest Regional Planning Commission. Every challenge Dave met during each of his endeavors would inevitably become a story that he would tell his friends and family when they visited him at the home he so proudly designed and built on Lake Champlain.

He is survived by his adventure partner and wife, Joyce (Heath); his daughter, Jennifer; his son, Andrew, and his husband, James Lynes; his sisters, Joyce (nee Leslie) Coffin and Trudi Leslie; his friend and brother-in-law, Arthur Heath; and many nieces and nephews.

Donations in his memory can be made to the Friends of Northern Lake Champlain, P.O. Box 1145, St. Albans, VT 05478, or online at friendsofnorthernlakechamplain.org.