BP: your summary is close enough. Treasury controlled UK citizens' access to $ until 1959, which is why so few UScraft were UK registered, and some of them via EI-, paid in £. Auster tried to match Piper/Cessna with A.6 Atlantic, but abandoned unflown. Peter Masefield moved from Bristol in 1960 to found BEAGLE, but 206/Basset, Pup/Bulldog were over-engineered so heavy, so uneconomical and the firm failed in 1968. Govt. did help, with Launch Aid (206) and RAF orders (Basset/Bulldog). Big firms chose to ignore genav: Shorts took licences for various Beechcraft, abortively. France, au contraire, sponsored air-mindedness, with subsidies for PPL courses and for club purchase of indigenous types. Cessna therefore made a licence arrangement with Reims Avn. who built/assembled many over 4 decades.