Which Way is That Thermal?

I was sent a link to a gadget some college engineers-in-the-making
built. http://engenius.sece.rmit.edu.au/Abstracts/Page601.htm. It
tries to detect which way a thermal is based on temperature differences
between wing tips. Bright boys.

I have two questions;

1) Have there been other gadgets created to do the same thing? How
well did they work?

2) What do you use to determine if the thermal is on the left or the
right? This is the wing up or down when its near the thermal debate.

Thanks, John

It's an old idea. Past attempts have failed because the temperature
gradients were too small to be detected reliably. Perhaps modern
sensors will work better.

As for number 2, there's really no debate. For conventional gliders,
the wing that goes up points in the direction of the thermal. Flying
wings may be a different story.



ContestID67 wrote:
I was sent a link to a gadget some college engineers-in-the-making
built. http://engenius.sece.rmit.edu.au/Abstracts/Page601.htm. It
tries to detect which way a thermal is based on temperature differences
between wing tips. Bright boys.

I have two questions;

1) Have there been other gadgets created to do the same thing? How
well did they work?

2) What do you use to determine if the thermal is on the left or the
right? This is the wing up or down when its near the thermal debate.

Thanks, John

Regarding apparent rising wings, that may not indicate anything
regarding the direction of the core of the thermal, other than a turn
may indicated.

That is, there is another school of thought on which way to turn,
especially if the goal is to center as quickly as possible in a
thermal.

Frank Whiteley

wrote:
It's an old idea. Past attempts have failed because the temperature
gradients were too small to be detected reliably. Perhaps modern
sensors will work better.

As for number 2, there's really no debate. For conventional gliders,
the wing that goes up points in the direction of the thermal. Flying
wings may be a different story.



ContestID67 wrote:
I was sent a link to a gadget some college engineers-in-the-making
built. http://engenius.sece.rmit.edu.au/Abstracts/Page601.htm. It
tries to detect which way a thermal is based on temperature differences
between wing tips. Bright boys.

I have two questions;

1) Have there been other gadgets created to do the same thing? How
well did they work?

2) What do you use to determine if the thermal is on the left or the
right? This is the wing up or down when its near the thermal debate.

Thanks, John

Which wing tip goes up? turn that way. Finger tips on the stick.. feel the
pressure...
Use the Force Luke..

BT

"ContestID67" wrote in message
ups.com...
I was sent a link to a gadget some college engineers-in-the-making
built. http://engenius.sece.rmit.edu.au/Abstracts/Page601.htm. It
tries to detect which way a thermal is based on temperature differences
between wing tips. Bright boys.

I have two questions;

1) Have there been other gadgets created to do the same thing? How
well did they work?

2) What do you use to determine if the thermal is on the left or the
right? This is the wing up or down when its near the thermal debate.

Thanks, John

Really? I had never heard of the "turn away from the thermal" school
of thought.



Frank Whiteley wrote:
Regarding apparent rising wings, that may not indicate anything
regarding the direction of the core of the thermal, other than a turn
may indicated.

That is, there is another school of thought on which way to turn,
especially if the goal is to center as quickly as possible in a
thermal.

Frank Whiteley

wrote:
It's an old idea. Past attempts have failed because the temperature
gradients were too small to be detected reliably. Perhaps modern
sensors will work better.

As for number 2, there's really no debate. For conventional gliders,
the wing that goes up points in the direction of the thermal. Flying
wings may be a different story.



ContestID67 wrote:
I was sent a link to a gadget some college engineers-in-the-making
built. http://engenius.sece.rmit.edu.au/Abstracts/Page601.htm. It
tries to detect which way a thermal is based on temperature differences
between wing tips. Bright boys.

I have two questions;

1) Have there been other gadgets created to do the same thing? How
well did they work?

2) What do you use to determine if the thermal is on the left or the
right? This is the wing up or down when its near the thermal debate.

Thanks, John

Yes, Frank, please explain this to us. I never heard that that there
was any other theory than turn toward the uplifted wing. Sure, there's
lots of theories about what to do after that. Bob Wander's "book" has
the 4-circle search method, and it seems like I read something in
Knauff's stuff somewhere, maybe in "Breaking the Apron Strings." I'm
still early in the learning process, and seem to have the best results
with "tighten the turn in decreasing lift, loosen the turn in
increasing lift. This works so well that I'm frequently seeing people
in roughly equal gliders climbing past me, so I'm always looking for a
better way. Enlighten us.

Thanks,
Ed

wrote:
Really? I had never heard of the "turn away from the thermal" school
of thought.



Frank Whiteley wrote:
Regarding apparent rising wings, that may not indicate anything
regarding the direction of the core of the thermal, other than a turn
may indicated.

That is, there is another school of thought on which way to turn,
especially if the goal is to center as quickly as possible in a
thermal.

Frank Whiteley

Suppose I'm flying along straight and level and I feel
the left wingtip rise. Where is the thermal? Is it
on the left and is it lifting the wing?

Or, is the right wing in sink and the wing is being
pushed down?

Does that mean there is a thermal further to the right
and the sink that pushed my wing down is the sink that
surrounds the thermal?

Which way should I turn?

For me, the answer is sometimes straight forward:
Turn the way my friends are turning because they got
there sooner than me!

Ray Lovinggood
Carrboro, North Carolina, USA

At 10:48 06 September 2006, Flying_Monkey wrote:
Yes, Frank, please explain this to us. I never heard
that that there
was any other theory than turn toward the uplifted
wing. Sure, there's
lots of theories about what to do after that. Bob
Wander's 'book' has
the 4-circle search method, and it seems like I read
something in
Knauff's stuff somewhere, maybe in 'Breaking the Apron
Strings.' I'm
still early in the learning process, and seem to have
the best results
with 'tighten the turn in decreasing lift, loosen the
turn in
increasing lift. This works so well that I'm frequently
seeing people
in roughly equal gliders climbing past me, so I'm always
looking for a
better way. Enlighten us.

Thanks,
Ed

wrote:
Really? I had never heard of the 'turn away from
the thermal' school
of thought.



Frank Whiteley wrote:
Regarding apparent rising wings, that may not indicate
anything
regarding the direction of the core of the thermal,
other than a turn
may indicated.

That is, there is another school of thought on which
way to turn,
especially if the goal is to center as quickly as
possible in a
thermal.

Frank Whiteley

"Ray Lovinggood" wrote in
message ...
Suppose I'm flying along straight and level and I feel
the left wingtip rise. Where is the thermal? Is it
on the left and is it lifting the wing?

Or, is the right wing in sink and the wing is being
pushed down?

Does that mean there is a thermal further to the right
and the sink that pushed my wing down is the sink that
surrounds the thermal?

Which way should I turn?

For me, the answer is sometimes straight forward:
Turn the way my friends are turning because they got
there sooner than me!

Ray Lovinggood
Carrboro, North Carolina, USA

At 10:48 06 September 2006, Flying_Monkey wrote:
Yes, Frank, please explain this to us. I never heard
that that there
was any other theory than turn toward the uplifted
wing. Sure, there's
lots of theories about what to do after that. Bob
Wander's 'book' has
the 4-circle search method, and it seems like I read
something in
Knauff's stuff somewhere, maybe in 'Breaking the Apron
Strings.' I'm
still early in the learning process, and seem to have
the best results
with 'tighten the turn in decreasing lift, loosen the
turn in
increasing lift. This works so well that I'm frequently
seeing people
in roughly equal gliders climbing past me, so I'm always
looking for a
better way. Enlighten us.

Thanks,
Ed

wrote:
Really? I had never heard of the 'turn away from
the thermal' school
of thought.



Frank Whiteley wrote:
Regarding apparent rising wings, that may not indicate
anything
regarding the direction of the core of the thermal,
other than a turn
may indicated.

That is, there is another school of thought on which
way to turn,
especially if the goal is to center as quickly as
possible in a
thermal.

Frank Whiteley






The only way is up.

Normally the thermal is the opposite way to the way you turn.

You guys must be coming towards winter tonight we are having our first taste
of summer thunderstorm in Sydney.

Summer bush fires blow fly's dust and 10 knot plus thermals bring it on.

Gee, thanks, Ray. :-)

I think it's safe to assume in this discussion that we're talking about
flying alone. If there are other gliders in a thermal, we're required
for many reasons to turn in the same direction that they're turning,
and the presence of other gliders gives us a good idea where to look
for the center. I have my best performance when I can use my neighbors
as thermal indicators. :-)

But this is a serious question. How can I improve my performance
centering thermals? Are all thermals surrounded by this ring of sink
you mention? And what if I fly straight into the middle of a thermal,
so that there's no lifted wing? What's the best technique to use then?

And what about speeds. Lets say I'm flying a Standard class glider,
with a min sink in the mid 40s and a best L/D of 38 at around 57 kt.
What should I be thermalling at in a typical eastern thermal? And what
angle of bank? I typically try to use around 45 degrees, but it isn't
constant until I get the thermal fairly well centered.

TIA (Thanks in advance),
Ed

Ray Lovinggood wrote:
Suppose I'm flying along straight and level and I feel
the left wingtip rise. Where is the thermal? Is it
on the left and is it lifting the wing?

Or, is the right wing in sink and the wing is being
pushed down?

Does that mean there is a thermal further to the right
and the sink that pushed my wing down is the sink that
surrounds the thermal?

Which way should I turn?

For me, the answer is sometimes straight forward:
Turn the way my friends are turning because they got
there sooner than me!

Ray Lovinggood
Carrboro, North Carolina, USA

"Frank Whiteley" wrote in message
ups.com...
Regarding apparent rising wings, that may not indicate anything
regarding the direction of the core of the thermal, other than a turn
may indicated.

That is, there is another school of thought on which way to turn,
especially if the goal is to center as quickly as possible in a
thermal.

Frank Whiteley

Yup, if you always turn toward the lifted wing, I guarantee you will be
right at least half the time.

Bill D