I had a little diagram in the Flying Models combat column a few years ago. Essentially its: if you are on the left and your plane went under untangle with an inside AROUND the other plane. Left-Over-Outside Right-Under-Outside Right-Over-Inside. This of course assumes you actually see the tangle coming and can see how you got into it. If you do get into a tangle and can't figure it out. Then the only thing to try is flying around each other a couple times in one direction. If that doesn't work, switch and go the other direction a few more times and hope.