Sink Is Not Just A Four-Letter Word
Gravity is the most relentless force on earth, and for soaring pilots it's the least forgiving. The highest performance sailplanes seem to laught at strong headwinds, but sink is SINK for every bird in the sky. Despite all our talk about lift - where to find it, how to use it - there is much more to soaring than that. Half the game of powerless flight is anticipating and avoiding sink, and knowing what to do when it has us in its cold, silent clutches. Because every form of rising air has a matching form of sink, understandging sink can also help us anticipate where lift might be. Whenever we recognize sink, avoiding it or getting through it must be our first priority. The answer to sink is always speed. But how much speed is enough and how much is too much? There is one theoretically perfect speed for every degree of sink, but when you have doubt about the exact speed, a smidge faster is okay. The penalty in altitude is no more than for going too slow, but achieved ground speed will be greater.