Well, to let the cat out of the bag, I have been looking at using a Brillelli 46GT or the new 36GT with the rear exhaust for this plane:

http://www.scottellingson.com/brillelli_002.htm

I don't think the 36 will have enough poke, even on a pipe, though. Scott lists the baseline prop as a Xoar 20x8 @ 6800rpm. From what I can tell, that really needs to be a 20x10 or 12 @ 7000+rpm for that stupidly overpowered feeling... The 36 IS 6oz lighter than the 46, though, which is very significant. But, unless it responds amazingly well to a pipe, I don't think it will be enough.

The 46GT is about the same weight as the standard ZDZ40 RE, maybe a few ounces lighter. That will be offset by needing a wrap around header to put the pipe or canister on the centerline of the plane. It should have fantastic power, with the baseline of a Xoar 22x8 @ 6500rpm. This equates to a 20x10 at over 7000rpm on the muffler and should be several hundred rpm higher with a pipe, giving a static thrust around 25lb from Pe Reivers thrust calculator. If that isn't enough to get OOS vertical with an 11lb model, I don't know what is...

I am not competing with this, it is only a sport plane for me, so the 11lb limit is academic. But I would like to keep it close for a nice light wing loading and the excellent flight performance that accompanies it. I figure I will be around 16-18oz heavier than Mark Hunt's 10lb 6oz prototype, powered by an OS 160. If I use a carbon wing tube and take care with the equipment, I should be very close to 11lb when done. I plan to finish with .75oz glass cloth and Minwax Polycryllic, which seems to be coming in right about equivalent with film coverings on weight, from what I have seen.


Mark