Completely tangential to this technical conversation:
I find it most interesting that the NACA research on early laminar-flow airfoils
found its first implementation in an aircraft designed for the export market. The British were visiting US manufacturers, and as the story goes, they asked NAA to become a second source for the Curtiss Kittyhawk. NAA countered with their own design, the NA-73, incorporating US taxpayer-funded research, and won the British contract.
Glad it all worked out in the end, but did NAA or the British ever compensate the US government for that research? There are modern examples of US manufacturers doing so when government-funded projects are reborn in the civil market (GE paid a royalty on CF6's for their TF39-based content, for example).
(Maybe this is Jet Blast material...)