Modern (plastic) gliders are painted white (I suppose for thermal reasons), except for some shapes on the fuselage (generally blue or red, but it seems the color does not matter). And the aircraft registration is dark, I suppose for maximizing the contrast.
Now, for the wingtips I noticed that there are two possibilities:
- white (nothing special)
- red marks
My question is: Why red? Is there something special that is preventing the wingtips from being painted in another color?