Screenshot Saturday - New wheels + Ground effect!

This week for Screenshot Saturday I'm showing off 3 new wheels.  Lets start out with the new tractor tires and the flying tractor:

I used the big tires to make the Pigaggio reversible.  Now it can land upside down!

They come in two sizes, large and small.  The third new wheel is the tiny castering wheel, which I immediately used to build a crazy drifting cart thing:

I also fixed the most glaring (to me) problem with the flight model by adding ground effect.  Of course, the first thing I did after implementing it was build an ekranoplan:

Let's keep the ball rolling with what I call the Unnecessarily Amphibious Flying Tractor:

Finally, here are a bunch of renders I made in blender.  I'm searching for both a new icon and a background image for a new in game menu.  I don't think I've found it yet.