Wheels on LT40 and Senior ARF
 

My LT40 needs some bugger wheels, but I am not sure how big. Currently it is a taildragger with 3" Dubros. I think there is just not enough prop clearence. I am running 11x6 on my 46FX. On the other hand, I have a Senior Kadet ARF I am building right now, that I replaced the main LG with a Dubro and I am planning on changing out the nose gear with a fults. My question is, in theory what is the optimal relationship of main to nose wheel heights? Should the nose be higher or lower than the mains? Or vice-versa? If the Dubro Main is 3.5" from the center of the axel to the underside of the fust, should I buy a fults that is 3.5 from the cetner of the avel to the bottom of the fuse? What size wheels should I use.

I realize I am asking a bunch of stuff here. Help is appreciated.

Wheels on LT40 and Senior ARF
 

I have been told that you don't want the nose of the plane lower than the mains because the angle will try to pin the plane down to the ground on take off. I went with the Dubro composite landing gear on my LT-40 and had to buy a longer nose wheel strut. I was advised to do this rather than use a larger wheel that I had to avoid excess drag. The plans show the distance from the ground to the bottom of the fuse at both the nose wheel and mains to be equal.

Wheels on LT40 and Senior ARF
 

Most trikes are more or less level, or a hair nose down. I've flown them nose down, nose up, whatever, as long as it's not too far off, it's not a huge deal. If it is too far off you can get problems.

If you are too nose down, the plane will "stick" to the runway and be hard to rotate for takeoff. Sometimes guys over-control trying to overcome the nose down, and leap in to the air, a bad thing. Nose down does make it a little easier to land though, since if you can get the wheels down on grass, the plane will usually stick, even if you "hot"

If you are nose high, it becomes really easy to leave the ground before you have flying speed, obviously a bad thing. It also makes it harder to land, as the plane will be more prone to bouncing back up in the air, you have get a good flair.

As for wheel size for grass, whatever it takes to get rolling smoothly. I used to fly off of a rather un-prepared field, and we used 3.5-4" foam wheels on .25 powered airplanes. And wed set them up really nose high to get up in to ground effect fast. Looked silly as all get out, with the wheels sometimes bigger than the fuse on some sticks. But we could get over the potholes and grass, and get airborne. :)

Wheels on LT40 and Senior ARF
 

As long as your low nose does not over ride your wing incidence you will be OK with a low nose. Nose High is OK to as long as you don't end up so high that you unicycle on the nose wheel...