True. However we can divide our material up. There is clearly a lot of
room for research. To illustrate the potential benefits of research let
me make a biological statement. Water is 1000 times denser than air (at
2,000m altitude). Dolphins and sharks swim at up to 70km/h. Putting
ther same energy in in air would = 700km/hr. Just a bit slower than a
passenger jet.

The Dolphin/Shark at pek energy will probably rougly equal a modern
250cc motobike engine. This is typical of microlight propulsion.
700km/h - Think about it.

I also feel that aircraft of all types would benefit, not just
microlights although for reasons of cost they make the best
experimental machimes. An airliner would have a lower optimal operating
altitude as induced drag (caused by the fact that the plane has got to
impart 9.81M m/s momentum downwards to fly. Induced drag goes down
with air mass swept.