Last year I did a bit of a survey of what's out there in the small aircraft space as I have a dream of one day building my own basic ultralight (similar rules here to what is called a Light Sport Aircraft in the US).
Most of the aircraft engines out there are based on either the VW bug engine or 1970's snowmobile engines. From what I've read it looks like it's mainly fear of liability that keeps newer designs out of the air. Just about any engine would be reliable if it's rebuilt every 300 hours, so long as it has a dry sump and intake preheat. The Yamaha Genesis series of snowmobile engines look like just the ticket... They have dry sump and preheat, but they also have much higher efficiency and lower emissions. Furthermore they have power density (130HP model is
In the STOL wingplan arena there's been a few experiments comparing full-length leading edge slots to wings with vortex generators. Vortex generators seem to provide almost as much lift at high angles/low speeds, but produce a whole lot less drag in cruise.
There's a few designs out there for propellers for small STOL aircraft that are quiet and efficient. The "Windspoon" by Duc Helices is an example.
Electric would be much lower emissions (especially where I live where almost all comes from hydroelectric or wind), but Lithium Polymer batteries are crazy expensive. A strictly airport-to-airport planned and schedulled service could do well with electric. I want to take my plane camping. Maybe by the time I can afford to build a plane the cost and energy density of batteries will make this possible.
I have an opportunity to shoot christmas photos coming up and I need my assistant to be able to do prints while I'm shooting and uploading via eye-fi.
Unfortunately aperture hot folder includes a nasty piece of code that throws in a "->" keystroke after every import, interrupting the user (although it makes for a nice live slideshow if you don't have someone doing prints and aperture is fullscreen).
"The way of the world is to praise dead saints and prosecute live ones." -- Nathaniel Howe