WHAT ARE THERMAL CURRENTS.
When a mass of warm air accumulates, it expands and becomes lighter (less density) than the surrounding air mass. The mass of that lighter air rises, but it also cools again due to the expansion. This process continued until that mass of air cools to the same temperature of the air that surrounds it, now that air stops its ascent. It is associated with the surrounding temperature downstream of the thermal column. The external lowering movement is caused by the cooler air that is displaced at the top of the thermal.
The size and strength of thermals are influenced by the properties of the lower atmosphere (the troposphere). Generally, when the air cools, the hot air bubbles formed by the heating of the air floor that is there, can ascend like a hot air balloon. The air is unstable. If there is a higher warm air layer, a reversal of the temperature can stop the hot springs rising, and air is available.
Thermals can sometimes be detected by the visible presence of cumulus clouds. When a gentle wind is a thermal wind, the clusters can be oriented in the wind.
Position of flight.
You have to be comfortable in the chair. I like to be leaning back, with arms resting on the bands, legs together in the most relaxed state possible. Sometimes I support my feet on the accelerator pedal.
Crusaders in general are elements of “antipilotaje" and usually do not recommend its use, included in the thermal flight, since it subtracts sensitivity to the piloting. However, it is an active safety element and some pilots.
Once we have located the thermal focus (we do not imagine where it is) we will go to the center where we “think" the thermal. When we enter the area of influence we can slow down a little to dampen the turbulence.
Normally, we will feel like one of the planes pulls more. So, what I usually do is open the turn a little to the opposite side, say a couple of seconds, and then change the turn to the other side, at first I start a 360 wide first that I’m closing gradually as I define the Core or nuclei of ancestry.
Sometimes it is possible to get a good core in a couple of spins but the normal thing is that it takes some tries and a few spinning investments to get the good. That is why patience is important.
When you lose the core repeat the operation, open the spin and start to close again.
To make good turns the first thing is to anticipate you looking through the path of the turn. Then we must involve the body in the piloting, for this we can help us by loading the weight and even passing one leg over the other. In general, the inner brake is used to fine-tune the turning-closing or opening more-and the outer one to compensate for small pressure losses. It is easy to see how the external brake must continuously operate as a shock absorber, compensating for small changes. This operation must become automatic and unconscious.
Normally it is not necessary to tilt more than 30º unless it is a very narrow and turbulent nucleus.
The ideal is to find the compromise between the size and strength of the ancestry and the rate of decline as inclined as we are.
The more turbulence, stronger ancestors and what we want are better offspring, we will have to get used to them and learn the habit of correctly and continuously compensating the turbulence.
In the vicinity of the thermal and its area of influence there are usually air movements, in some cases so strong that we can get to fold the candle. Therefore we must “extend" the technique of compensating the pressure, applying a brake on the side that loses pressure to the point that we notice that we recover it, and then the hand will practically go up alone when the correct pressure is restored. Sometimes it is necessary to lower the brake to the bottom. It is also possible that abruptly we lose pressure on the inner side, it is a matter of being attentive.
This can be happening continuously during a thermal movidita so we must habituate and turn it into a reflex act and accepted
Strong but with silk hands
There are specific moments in which we must command strongly, but the characteristic of a good pilot is the smoothness and progression in his commands and this is applicable even when it has to be sent with force. The paraglider must be felt as an extension of the pilot himself and act smoothly, interacting with the sail and feeling the nuances it conveys to act accordingly.
Turning with wind.
Another factor to take into account is the drift caused by the wind. As little wind as possible, it will always deform the thermal with its strength. This is not something mathematical, sometimes a thermal becomes so strong that it rises right upwards overcoming the influence of the wind. But it is normal that he bow and that we take this inclination into account as we climb so we do not lose the core.
– He uses his body a lot during riding. Reserve the brakes for corrections.
– If you really want to get to the level of the thermals, try flying the morning thermals and try to take advantage of the first ancestors that are much more difficult.
-When you fly near the ground, never give up a 0-however little it seems to you. Normally, if you endure enough, another thermal will be released.
– It is always better to fly a little fast, with a speed reserve that you can use for a correction that requires agility.
– To initiate you to the thermal flight uses a paraglider that has very easy and that absorbs well the turbulence.
– Adesérate and begin in a place that is characterized by the softness and not by the strength of its thermals.
– Take advantage of the soft hours, Between 12:30 and 4 is usually very strong, sooner and later, better. As you begin to master the technique you can extend the time
(By Daniel Crespo Valdéz, published in Parapente Vuelo Libre magazine)