This is an edited extract of an article in Fifty Ways to Fly Better, by Bruce Goldsmith and Friends
Thermalling is probably the most important part of flying, as well as the most pleasurable. The feeling of using the natural energy of rising air is a pleasure similar to surfing an invisible wave. But the pleasure of thermalling like a bird is also closely linked to the feeling of being connected to the air through your wing. The better you are in harmony with your equipment the more you will enjoy the feeling of thermalling.
Feeling is what a bird uses to thermal better. It is an instinct, a way of feeling the air and using the information you get to better use the thermal. It is all about the decision to search out new, stronger areas of lift or to stay and climb in the strongest lift you are in. This balance of whether to search or to stay is super important
In your search for the best lift, observation is one of your most important tools. There can be many different visual clues as to where the best lift might be. The most obvious is other gliders or birds climbing better than you, but also insects being swept up in the core of the thermal or even a few stems of grass, a plastic bag or a single dry leaf can give you the vital clue to where the best lift is. My favorite is swallows: they fly super fast and are hard to see, but they constantly search out the best lift, flipping from one updraught to another in their endless quest for insects to eat.
Try to understand where the thermal came from, what was the thermal source. Also look at where the thermal is going to. By that I mean look at the cloud formations above you and try to understand if your thermal will form a new cloud or if it is going to join part of an existing cloud formation. Looking at what the clouds have been doing over that area in the last 15 minutes will give you some good clues about how to answer this question.
Use little brake and more weightshift
Weightshift is a more efficient way of turning than using the brakes. This also means that you will be flying faster in thermals which makes it harder to stay in the core, so more concentration and skill is required to stay in the core using this technique.
Do not use trimmers in the slow position
If you have your trimmers on slow then the glider may tend to sit back a little sometimes and you will not get the best climb rate out of it.
Try to turn in the best lift
It may be a rather obvious statement but you should make every effort to try to turn the sharpest when you are in a surge of lift. This means that you will spend longer in the lift. Also, the surge of lift will go some way to compensate for the reduced sink rate you get when you turn. I often try to imagine that I am grabbing hold of a lump of rising air with my brake when I turn sharply into a bubble of lift.
Never be content with the lift you are in
Thermalling is a never-ending search for stronger lift using all your senses. Never be content with the lift you are in, continually search for better, and search for new areas of lift using all the information at your disposal, what you see and feel through your harness as well as through the brakes. Thermalling is a kind of state of mind, each thermal is different and an invisible puzzle to explore so you get the fastest climb out of it. That’s what makes thermalling such a pleasure.
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