I share the concern about the hinges -- it is very easy to nudge the bottom one slightly loose (sideways) if there is any binding at all, and given it takes most of the force of the rudder horn, once it becomes loose there is room for movement. IMHO it needs to be under continuos watch. I also have a concern over the 1/2" or so of exposed hinge shaft -- I know it is tough and there is probably ne reason (and I am not having a go at anyone) but it still worries me. While there is much discussion on the damage flutter can cause on these fuz's, and how to minimise impact of it, the engineer in me wants to remove any possible weak points or possible causes. I am not sure, but I think the Impact may be one of the few/only C-ARF planes with the rudder done this way.

I am just starting builidng a second one (cos I really like how they fly), and am going to replace the provided rudder with a foam/balsa sheeted one, put in a new tail post extending past the back of fuz, bevel the edges of both, and hinge it the proven way (I tend to use Hayes hinges) where there is as little as possible scope for movement. I guess the counterbalance will need to be carved from balsa -- and given it is the Impact scheme I may need to do some paint matching and air brushing! Other than the painting it should be very straightforward.

I may also (once I am set up to do it the way above) have a go at trimming the front of the provided rudder (the round, glass section at the hinge line) and replacing it with a balsa leading edge as suggested above -- it is good idea, but I would like to compare relative weights.

On the u/c and wheel pants I also made some mods. I fly off grass usually and found those big tough bits when the mowing wasn't perfect would get stuck between the pants and the leg, and there really isn't much strength in the very end of the leg -- and one very big tough bit broke the axle out the end of the leg (fortunatley right at the end of the roll-out on landing)! So I shortened the leg 10mm, put a fillet on the end so it snugged right up to pants without any gap to catch things in, and haven't had any issues since. I am using Dave Brown lite wheels on the NMP axles as they are so simple to mount -- but I replace the provided 4-40 screw provided with a standard 4-40 hex headed bolt as I kept stripping the heads on teh provided ones.

David