Libelle thermalling techniques

[AdamLibelle]

Hi,

I have recently started flying a Libelle H201b and I don't think I am
quite making the most out of it's thermalling ability. Can anyone give
me any idea of the best speeds to fly in the thermal and any other
useful info.

Adam

[Fred[_1_]]

Adam:

In my experience, the Libelle 201 thermals like any other sailplane,
except it has light wing loading and climbs like a homesick angel in
light lift. The secret to thermalling that is often overlooked in
instruction is speed control. If you're speeding up and slowing down
you don't know where the lift is -- you just keep making irregular
ovals in the sky. Watch the horizon and keep the it a constant level
on the canopy. Go for it. Fred


AdamLibelle wrote:
> Hi,
>
> I have recently started flying a Libelle H201b and I don't think I am
> quite making the most out of it's thermalling ability. Can anyone give
> me any idea of the best speeds to fly in the thermal and any other
> useful info.
>
> Adam

[Udo Rumpf]

In my experience this is true only if the thermal is
smooth and uniform. If this is not the case then it
may be best to follow the surge as the glider passes
through stronger rising air. This would be indicated
by the glider accelerating, at this point you would
pitch up to your normal best bank/minimum sink speed.
When reversed the speed wants to bleed off, at that
point one would want to pitch down. The later does
not happen to often in a thermal as there is residual
positive lift. The key is to watch for those acceleration
which at times can be pronounced and one has to respond
very quickly to take advantage of that, also there
is the point of maybe opening or tightening up the
turn as the surge may indicate the centre of the thermal.

For an other glider pilot watching from an other point
of view, this may not look as pretty but it is effective.
Regards
Udo
At 14:42 04 September 2006, Fred wrote:
>Adam:
>
>In my experience, the Libelle 201 thermals like any
>other sailplane,
>except it has light wing loading and climbs like a
>homesick angel in
>light lift. The secret to thermalling that is often
>overlooked in
>instruction is speed control. If you're speeding up
>and slowing down
>you don't know where the lift is -- you just keep making
>irregular
>ovals in the sky. Watch the horizon and keep the it
>a constant level
>on the canopy. Go for it. Fred
>
>
>AdamLibelle wrote:
>> Hi,
>>
>> I have recently started flying a Libelle H201b and
>>I don't think I am
>> quite making the most out of it's thermalling ability.
>>Can anyone give
>> me any idea of the best speeds to fly in the thermal
>>and any other
>> useful info.
>>
>> Adam
>
>

[Udo Rumpf]

Ideally this is the case
In my experience this is true only if the thermal is
smooth and uniform. If this is not the case then it
may be best to follow the surge as the glider passes
through stronger rising air. This would be indicated
by the glider accelerating, at this point you would
hold / pitch up to your normal best bank/minimum sink
speed. When reversed the speed wants to bleed off,
at that point one would want to pitch down. The later
does not happen to often in a thermal as there is
residual positive lift. The key is to watch for those
acceleration which at times can be pronounced and one
has to respond very quickly to take advantage of that.
If the response is quickly the flight path can still
look smooth but as a surge becomes stronger the flight
path may become erratic looking. Also there is the
point of maybe opening or tightening up the turn as
the surge may indicate the centre of the thermal. For
an other glider pilot watching from an other point
of view, this may not look as pretty but it is effective.
Regards
Udo




At 14:42 04 September 2006, Fred wrote:
>Adam:
>
>In my experience, the Libelle 201 thermals like any
>other sailplane,
>except it has light wing loading and climbs like a
>homesick angel in
>light lift. The secret to thermalling that is often
>overlooked in
>instruction is speed control. If you're speeding up
>and slowing down
>you don't know where the lift is -- you just keep making
>irregular
>ovals in the sky. Watch the horizon and keep the it
>a constant level
>on the canopy. Go for it. Fred
>
>
>AdamLibelle wrote:
>> Hi,
>>
>> I have recently started flying a Libelle H201b and
>>I don't think I am
>> quite making the most out of it's thermalling ability.
>>Can anyone give
>> me any idea of the best speeds to fly in the thermal
>>and any other
>> useful info.
>>
>> Adam
>
>

[Udo Rumpf]

Please ignore the first message,
the second one expresses it a bit better.
The first one slipped through.
Udo

At 16:24 04 September 2006, Udo Rumpf wrote:
>Ideally this is the case
>In my experience this is true only if the thermal is
>smooth and uniform. If this is not the case then it
>may be best to follow the surge as the glider passes
>through stronger rising air. This would be indicated
>by the glider accelerating, at this point you would
>hold / pitch up to your normal best bank/minimum sink
>speed. When reversed the speed wants to bleed off,
>at that point one would want to pitch down. The later
> does not happen to often in a thermal as there is
>residual positive lift. The key is to watch for those
>acceleration which at times can be pronounced and one
>has to respond very quickly to take advantage of that.
>If the response is quickly the flight path can still
>look smooth but as a surge becomes stronger the flight
>path may become erratic looking. Also there is the
>point of maybe opening or tightening up the turn as
>the surge may indicate the centre of the thermal. For
>an other glider pilot watching from an other point
>of view, this may not look as pretty but it is effective.
>Regards
>Udo
>
>
>
>
>At 14:42 04 September 2006, Fred wrote:
>>Adam:
>>
>>In my experience, the Libelle 201 thermals like any
>>other sailplane,
>>except it has light wing loading and climbs like a
>>homesick angel in
>>light lift. The secret to thermalling that is often
>>overlooked in
>>instruction is speed control. If you're speeding up
>>and slowing down
>>you don't know where the lift is -- you just keep making
>>irregular
>>ovals in the sky. Watch the horizon and keep the it
>>a constant level
>>on the canopy. Go for it. Fred
>>
>>
>>AdamLibelle wrote:
>>> Hi,
>>>
>>> I have recently started flying a Libelle H201b and
>>>I don't think I am
>>> quite making the most out of it's thermalling ability.
>>>Can anyone give
>>> me any idea of the best speeds to fly in the thermal
>>>and any other
>>> useful info.
>>>
>>> Adam
>>
>>
>
>
>
>

[bagmaker]

There is an interesting series of articles on thermal rotation in the last couple of Soaring Australia magazines (www.soaring.com.au) -although I am not sure how you would access them in the USA. They state the difference in circling direction/vs speed/gust roughness/etc in great detail and has caused more than a little debate at recent club get togethers.
My theory is to crank it over hard, go against every gust or deflection and relax.
If your not going up in a Libelle, its not going to be the libelle thats the problem!

Bagmaker

[AdamLibelle]

Thank you very much for your help. I intend to try the ideas out on the
next thermic weekend!!