56mpg at 138mph?

[elhigh]

Originally Posted by ebacherville

wonder what kind of MPG those powered parachute things get.. at least you could fly from point a to b directly and never stop till you arive..

Their fuel efficiency is atrocious. Speed under full throttle: 30mph, idling: 20mph. The ram wing is a great way to generate lots of lift at low speeds in a low mass form, but it costs at the pump.

[Otto]

That plane has only scratched the surface of aircraft fuel efficiency. Per research and development by aerodynamicists including Bruce Carmichael, Alex Strojnik, and Sig. Hoerner, a much more streamlined plane could be built and go faster on less fuel, using lighter weight and better aerodynamics such as laminar flow.

Consider that the not-too-good Sweitzer 2-32 sailplane is efficient enough with a ~49' wingspan to maintain level flight at ~60 mph on ~2 hp of thrust. That Sweitzer, btw, is a dog compared to current German sailplanes.

Whittle that plane down to half the size, weight, and wetted area, clean up its rough spots, any you'll get substantially better mileage.

In fact, ~30 years ago the Quickie got over 100 mpg flying at better than ~100 mph on an 18 hp Onan engine, like used in Winnebagos for aux generators. The Quickie, btw, was not the end-all and be-all of homebuilt planes. Small and light, though.

[Who]

Imagine the mileage over open water while flying bravely in ground effect.

[Otto]

Originally Posted by Who

Imagine the mileage over open water while flying bravely in ground effect.

I used to be more enthusiastic about ground effect vehicles, until I realized that you have to go to all the trouble and expense of aircraft construction, but then have a vehicle that only goes over water, often in poor visibility and wx conditions.

Better to climb above all that, the bad weather, and terrain, with a real airplane that can go anywhere on the earth's surface.