I rented this from Netflix.
It is a two-part series about the work of John Harrison, a Yorkshire carpenter, in the mid-1700's to devise a precise clock that would work at sea to determine longitude, by comparing solar time and the known precise time at the point of departure. There is also a parallel story about a naval officer subject to nervous breakdowns named Rupert who restored Harrison's clocks in the 1930's. It is fascinating and quite well done. Surely something Plane would enjoy.