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Here are a few  tips to help improve your thermal flying.

 1. Listen to your variometer. As you hear its pitch increase, indicating stronger lift, straighten up your flight path a bit so that you fly deeper into the strongest part of the thermal. When your vairos pitch decreases, indicating weaker lift, tighten up your turn to get back to where you just came from. If your variometer indicates a constant rate of climb, circle as flat as possible.

Climb rate increases -> Widen your turn
Climb rate decreases -> Tighten your turn
Climb stays the same -> Turn as flat as possible

2. Fly with your GPS zoomed in to about 200m. At this setting you can easily see the circular track log left while coring a thermal. If you inadvertently drift too far in one direction and fall out the side of the thermal simply look at your GPS track log to guide you back into the thermal.

3. If you’re flying downwind and you enter a thermal start your turn immediately.The strongest lift is usually found on the upwind side of a thermal. By doing this you will avoid flying out the back side of the thermal and into strong sink.

4. If you are flying upwind and you enter a thermal continue to fly straight until you either fly into a strong core or fly out the front edge of the thermal. While flying upwind it’s no big deal to flying out the front edge of a thermal as you can simply make a 180 degree turn and with the aid of a tail wind fly back in the thermal. 

5. If you need to reverse your direction in a thermal, wait until you are on the upwind side, then make your direction change by turning into the wind. If you end up flying out of the thermal it will be on the upwind side. As you complete your turn you will have a tailwind to help push you back into the thermal. See the illustration below.

5. Be aware of your chest strap setting while thermaling. In order to feel the thermals better, loosen you chest strap so that your carabineers sit farther apart. If the conditions start to get too turbulent you can tighten your chest strap up a bit which will dampen out the bumps.

There are a few other things to keep in mind in regards to chest strap settings.

Wide setting:

• Less likely to getting riser twists.
• You will be able to feel the thermals better in your seat.
• If you take a asymmetric collapse it is even more important that you lean away from the collapse. If you don’t the wide chest strap setting will cause you to weight shift in the direction of the collapse, which will result in a significant change in heading and in most cases a more violent recovery.

Tight setting:

• Dampens out the bumps.
• Turns less when recovering from a deflation (safer setting for beginners).
• More likely to get riser twists. Counter this by sitting up in your harness and being ready to turn with your glider if you feel a deflation is likely do to excessively turbulent air.  

1. When thermalling, fly deeper in the brakes.. almost carabiner level.  Better pressurizaton, less pitching, occillations.  I was flying right through a bunch of the juicy stuff and getting tossed over the waterfall on the backside. 

2.  When on speedbar, fly with your fingertips on the stabillos.  “Checking” the glider with the stabillo lines in the event of a frontal is apparently a better method than Ds or toggle pressure… all the comp pilots were talking about this “new” technique.

3.  Search upwind for the thermals and don’t be afraid to push out front.  The “yo-yo” technique was mentioned quite a few times, i.e. drifting with the core then pushing back out front if you fall out of lift.

~ Chris C.

So you’ve found your climb – now what’s the best way to use it?
by Jay Rebbeck, Published: 27-Aug-01 X-C Magazine

Centering thermals efficiently, and climbing quickly, are probably the most fundamental skills you need to soar successfully. Even a small improvement in your technique could easily mean an extra few hundred feet in every thermal – or thousands of feet in a typical XC flight of, say, 10 thermals. Come the end of the day, this might even make the difference between getting home and landing out. In a competition, what you gain in improved climb rate could well equate to the points separating the winner and mid-table obscurity.

THINK IT
Before you even reach a thermal, you can start building a mental picture that will help you center and climb quickly when you get there. Typically, you will be approaching a cumulus hoping to climb. You can improve your chances of finding a thermal by assimilating all the experience gained on that day to guess where the thermal might be in relation to the cloud. While on some days, thermals appear to form randomly, there are others when you can find them quite reliably. For example, if a strong wind and bright sunshine were feeding a cloud from one direction, you would expect to find the thermal on that same side.

FEEL IT
As you approach the area where you expect the thermal to be, hold your brakes very lightly. Other than maintaining a good lookout, you should be totally focused on feeling which side the thermal is. If the thermal feels strong enough, turn towards the wing that’s lifted.
After you have rolled and turned into the thermal, one of two things might happen: If the lift steadily improves, great. But what should you do if the lift drops into sink?
The answer depends on how good the surge felt and how desperate you are to climb. If you weren’t confident of the lift when you started to turn and the clouds ahead look good, then simply roll out and get going – if you’ve got the height. However, if the surge felt smooth and solid, but you turn into sink, then you’ve probably turned the wrong way. At this point FORGET any distractions about what techniques to use, and resort to a mental picture. Logically, the quickest way back into the center is to do a tight 270° turn, and then re-center. This maneuver brings you back to where you would have been if you’d turned the right way in the first place! You’re now in a position to maximize your climb.
Despite the enormous importance of climbing quickly in thermals, this is one of most controversial topics in free flying. Most people want to be taught a prescriptive technique for thermalling, and this is where the confusion begins. There are two widely-taught techniques, but they appear to be completely contradictory. The tighten on the surge theory says that when the vario indicates the greatest climb rate, you should increase the angle of bank. In apparent contrast, the second theory says you should widen out when encountering the strongest lift. So how do we resolve this contradiction? The answer is that both theories are right, but they are appropriate in different situations.

TIGHTEN ON THE SURGE
So, having positioned your glider in the thermal, how do you establish yourself in the center and optimize your climb rate? The answer is to use the tighten on the surge technique: when you feel the thermal pushing solidly, or the vario indicates the strongest lift, you should tighten the turn and dig the wing into the thermal. Most pilots don’t turn tightly enough, but of course, if you only tighten up in lift you’ll end up in a spiral dive! To prevent this, when the vario indicates weaker lift or sink, you should widen the turn out to anticipate banking and pulling into the next surge.
The importance of tightening on good surges was brought home to me during the 1997 World Air Games in Turkey, where I was competing in the gliding section. Climbing in hot, blue thermals with massive gaggles in identical-performance gliders, often the only way to achieve an advantage on anyone else was simply to get stuck right in to the core of the thermal. The pair of flying French pilots who went on to win always managed to center on the strongest cores.

WIDEN OUT IN THE STRONGEST LIFT
Tightening on the surge is the technique for staying centered in one core of a thermal. So what is the role of the opposing technique of widening out in the lift? Quite simply, this should be used when you think there is a developing core nearby. But how can you recognize this emerging fresh bubble?
Having centered on one core, there are a few tell-tale signs: first, the average rate of climb drops off and, second, the thermal seems much stronger on one side than the other. Another core has formed, is bumping up the side of the one you are in, and the outflow from that bubble is interfering with yours. Sometimes this is marked by birds or other gliders circling, or tendrils being sucked into cloudbase nearby. In any case, the solution is simple: widen out in the strongest lift, wait a few moments, and then tighten up in the emerging bubble. Then continue to stay centered in the new pulse of lift using the tighten on the surge technique.
The ability to re-center quickly can sometimes be the key to competition success. On a critical day in the Junior Gliding World Championships in Holland, I was able to gain enough height on the gaggle in just one thermal to make it home as the sole finisher. What made the difference that day was simply that I re-centered efficiently and caught a short-lived bubble which the rest of the gaggle missed. That turned out to be the last thermal of the day, giving me enough height to glide home over the unlandable forest, while everyone else hit the deck the wrong side of it.
There is a strong correlation between the width of a cumulus and the number of bubbles feeding that cloud. For example, when arriving under a vast cloud street you should expect loads of bubbles and will probably need to widen out into wind frequently when you feel a fresh surge. On the other hand, climbing under the last isolated cloud of the day, you are likely to have to rely on simply tightening on the surge to get you home.
Whichever style you adopt, if you want to climb fast, you have to keep working it all the way to the top! You’ll also need to be planning where you’ll go when you leave the lift.

So what is a thermal anyway? Well it’s pretty simple, a thermal is created when the sun heats the earth which in turn heats the layer of air directly above it. As this layer of air warms up the molecules spread out causing it to become less dense and therefore lighter than the air surrounding it. When the temperature difference becomes great enough the air breaks away from the surface and begins to rise, much like a hot air balloon.

However as a thermal begins to rise the surrounding air pressure decreases which allows it to spread out and now it’s temperature begins to drop. This drop in temperature do to a decrease in air pressure is known as Adiabatic cooling.

As long as the air temperature inside the thermal remains higher than the temperature of the surrounding air the thermal will continue to rise.  

To read more information about thermals and paragliding weather in general see Understanding the Sky by Dennis Pagen.

When flying in a thermal it is very helpful to have a reliable vario like the Flytec 6005.