The hovercraft kind of sums up some of my memories of the late 60s/early 70s Britain. Patriotic but struggling to find some sort of modern justification for that patriotism. Hey we can invent cool things like ... er ... I know hovercraft! They were the patriotic "I'm backing Britain" answer to everything but turned out to be at best niche, and generally commercially a bit useless.
Maglev trains. Concorde. Hovercraft. Cool ideas that flopped rather.
The Harrier jump jet and the QE2 are also part of my memories of that period although they were probably somewhat more successful.