Geordie Mainland's role in the momentous events of D-Day - the largest ever seaborne invasion - is a key event in his life story. The operations of the 712th Landing Craft Personnel (Survey) Flotilla are not generally known. Theirs is a largely forgotten history and Geordie's single surviving voice is therefore all the more important.
But the Normandy landings apart, Geordie's life spans almost a century of unparalleled and tumultuous technological change.
The world may have changed utterly, but the boy who was always interested in machinery and how things work took it all in his stride - the dizzying speed of technological innovation held no fear, just continued fascination.