CALCULATIONS ON SOARING SINK

As discussed in the article 'Dynamic Soaring and Sailplane Energetics', there is just as much energy in the motion of sinking air as in rising air. It is, however, quite a bit more difficult for a glider to get power from downward moving air. Getting energy from sink requires negative g's or inverted flight. The energy a glider gets from sinking air generally appears as extra speed (kinetic energy). There is also frequently a loss of height as the kinetic energy increases. Still, the increase in kinetic energy can far exceed the loss of potential energy due to loss of height. Below are some calculations demonstrating how sailplanes can get energy from sinking air