"jóse" wrote:

> I fly a HG, three years from now...(by the way not always as safely as a
> should...) And I've always wonder if it's posibble to fly a thermal
> without a
> vario...It is? In that case...What would be the process to follow...?
> Jóse Ramon Santín Miguel.

Jóse:
As a start, you MUST have enough altitude to circle a few times, fall
out of the side of the thermal, recover, and then, fly to a safe landing
area. You can lose 50 meters of altitude, and maybe more, when you exit a
thermal unexpectedly. When you get too low, it is safer to avoid a
thermal. This is very important to your health.
Now, from a safe altitude, you will be flying along and feel the glider
start to rise. Maybe the nose will go up first. In that case, pull the
nose down enough to fly straight into the thermal. A very strong thermal
can overpower you, raise the nose too high, and reverse your flight path.
You need to turn back to your original course, add more speed, and hit the
thermal again, but harder. This time, keep the nose down until you enter
the thermal.
A wingtip may rise up instead of the nose, telling you that there is a
thermal under that side of the glider. If you can, pull that high wing
down, turn 90 degrees toward the side that lifted, and enter the thermal.
If the thermal overpowers you, so that you cannot turn into it directly, the
glider will want to try to turn away from the thermal. Let the glider turn
away, 90 degrees in the wrong direction, then make a 180 degree turn back to
the thermal and fly straight into it, as described above.
You will need enough thermal (lift) to be behind you, to give you room
enough to circle. So, when the nose lifts, continue to fly straight across
the thermal for several seconds (count to five or more), then begin your
circle by making a hard 90 degree turn. Once you have flown across the
thermal and made the hard turn, let that hard turn flatten out somewhat, so
the hard turn becomes a nice, smooth circle. You want to do all of this
slowly in large thermals, and rapidly in small thermals. This smooth circle
must fit in between the place where the nose went up, and the place where
you made the hard turn. Relax and let the glider circle and climb.
Now you have probably noticed that it is very difficult to tell if you
are climbing or descending, by looking straight down. This just does not
work unless you have a lot of experience, and poorly even then. There is a
better way.
If there is a hill near where you are circling, choose any rock, bush or
landmark on the hill that is exactly at your altitude. Every time you
complete one circle, compare the angle you see your landmark from. If you
find that you are soon looking downward at it, then you have climbed.
Looking up for your landmark tells you that you are descending. In either
case, immediately disregard your old landmark and choose a new one, exactly
at your altitude, and begin again. This works well if there is a hill close
by, whether you are thermalling or just flying around in good lift.
Now suppose that you have thermalled high above your little hill, and
there are no landmarks to be found at your altitude. Here comes the
secret. Picture in your mind a lever and fulcrum system, such as might be
used to move rocks. In the case of thermalling, the "lever" is your line of
sight, and the "fulcrum" is any hilltop or ridgetop that is visible in the
middle distance, as long as some terrain is visible past that hilltop. You
are not interested in the fulcrum, it is only a pivot point. You want to
look at the terrain above (past) the fulcrum. This fulcrum may be a
kilometer away, or even ten kilometers (or more) away. On each circle you
make, you are very interested in the terrain that you can see behind your
high point or fulcrum. As you can see more scenery behind your fulcrum, you
are climbing. As you can see less scenery behind your fulcrum, you are
descending - the fulcrum is now blocking more of your view. As you get even
higher, you can disregard your old fulcrum and choose another, even farther
away - as long as you can see any scenery beyond it. A fulcrum with only
the sky behind it would be useless for our purpose, which is to judge your
increase of altitude.
The best fulcrum is always a high point, at a slightly lower altitude
than you, located less than halfway between you and the farthest scenery
that you can see clearly. This gives you the most noticeable change in
scenery as you climb or descend.
If this procedure was not clear, I will explain more if necessary. You
might want to print this message, because each aspect here is important to
you.
All the best to you,
Red

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