I must say that as a 3D printing enthusiast I've been following these developments with great interest. I wonder, Dave if you are able to source the LW PLA that I've been playing with down there in Adelaide? Once you've got the printer 'tuned in' it is very nice stuff to work with. It could be just the ticket for fabricating ducts.
The second thought that crosses my mind is that some form of reaction powered R/C might be possible with some of todays minature R/C gear. Types such as the Me163 and the EE Lightning naturally suit an intial full throttle climb out and a coast back to land. I'm no expert on R/C hardware. I'd be interested if you could suggest a configuration that might suit (that doesn't have a battery eliminator circuit as part of a motor speed controller.)
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