Iv'e noticed that if the plane is far away, you see the plane at an angle and therefore don't see the bottom of the plane any way. Therefore making the bottom of the plane a different color doesn't really make any difference if the plane is way out. I keep it up high and if I am not sure if its inverted or not I pull up elevator. If the plane goes up, its right side up, if it goes down, its inverted and I keep pulling until it circles back to right side up. Make sure you have a bit of altitude before you do this. For colors I like Neon yellow and as someone mentioned you ned at least a 4" wide strip. Smaller than this and the even the yellow turns a muddy brown when it gets further out. I had a Zero that had Metallic blue with Neon Yellow strips and it made it really easy to see what the plane was doing and land. I recently saw that you can buy Monokote with Black and yellow squares. They would be very good for the bottom of the wing. [8D]