On the morning of April 18, 2023 Seaforth “Si” MacCallum Lyle passed away at his home in Naples, Florida. He was 86. Seaforth was born in St. Lambert, Quebec to Elizabeth Ahern and Andrew Seaforth Lyle. He attended McGill University in Montreal, Quebec where he received both a Bachelor’s and a Master’s degree in Electrical Engineering. He later attended Imperial College in London where he met and married Joan Leone Gunston in 1962. The couple moved back to Ontario, Canada and had two

children, Katherine and Scott.
In the years that followed Si worked for companies including Westinghouse, Litton Systems and Digital Equipment Corporation’s Canadian headquarters in Ottawa, Ontario. In 1976 Si took a job with Digital Equipment’s US headquarters in Maynard, Massachusetts and the family moved to Sudbury, Massachusetts. In 1979, Si was promoted to Vice President of Engineering for Digital and in the same year he joined NASA’s Technical Advisory Board. In 1984, Si joined Banyan Systems in Westboro, Massachusetts as Executive Vice President.

When he wasn’t blazing trails in the computer industry Si enjoyed model railroading and built an extensive train layout in his Sudbury home. Upon his retirement and subsequent move to Naples,
Florida in 2004 Si volunteered his engineering and marketing skills with the Naples Train Museum. On any given Tuesday one could find Si rewiring the model train layout and coming up with promotional ideas to improve attendance. Si is preceded in death by his granddaughter Erica, survived by his wife Joan, daughter Katherine, son in-law Eric, son Scott, daughter in-law Leah and two grandchildren Keira and Nolan.

Memorial service arrangements to be announced at a later date. In lieu of flowers, please make a donation to the Naples Train Museum 401 10 th Street South, Naples, Florida 34102.