I think you are correct, the stock Rotax silencer will have to go! From the perspective of ear comfort during flight I had thought to keep it. I don’t think it’s a tuned exhaust so going to open pipes shouldn’t be a problem. On the other hand I think it might be possible to make/buy some small, light, in line silencers that could package alongside the fuselage, in the airstream, that would take the edge off the noise.
Knowing that the big silencer box is gone allows me to move forwards knowing that there is a solution, but I’ll deal with that another day!
