Listening to R4, a documentary on Roald Dahl had him talking about how a fellow aeromodeller, Stan Wade, who made his own aero engines worked with him to produce a cerebral shunt after he was dissatisfied with those supplied for his baby son after he suffered hydrocephalus after a terrible accident.
I'm sure this is the same Stan Wade who wrote "A Model Plane's Engine" in ME 2338 of 1946.
Both men agreed to accept no profits from the invention.
Neil