Thermal generating

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Re: Thermal generating

Postby Bill Cummings » Wed Apr 20, 2016 5:55 pm

Hot spring opportunities (Thanks for reminding me, Joe F.)
Minnesota had a lot of shallow swamps. They gave off heat at the end of the day longer than bare ground would.
Switching to thermaling over these swamps near the end of daylight would have me coming out of the air a half hour before sunset.

How about over a power plant water cooling pond
For years Minnesota Power and Light Co. kept Colby Lake from freezing over all winter long even through minus 30 degrees (F).
Sea Gulls would thermal up over the lake to glide 50 miles to Lake Superior which also seldom froze over during the winter.
Many days during the winter with snow covered ground surrounding Lake Superior the Radio data buoys would indicate the wind moving toward the lake from all directions. Sea Gulls could be seen soaring all day without flapping.
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Re: Thermal generating

Postby Bill Cummings » Thu Jun 16, 2016 6:48 pm

Joe's post, above, reminded me of a 50 plus mile flight from towing at the Las Cruces International Airport and gliding to a town called Hillsboro, NM.
After squeaking over the San de Los Uvas Mountains I made it to the cow ranch on the north side of the mountains. The smell of cow fertilizer had me turning back looking for the stinkiest part of the thermal. :shh: Pilots with a good sense of smell (not me) probably have used smell to initiate a search pattern for lift. (The nose knows.)
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Re: Thermal generating

Postby Bill Cummings » Tue Apr 28, 2020 7:24 pm

Twenty five years ago The Duluth Skyline Sky Dogs signed waivers and a landowner (Tommy Thompson) let us tow
on the dirt roads on the property that he farmed. He had a government grant to drain the peat bogs between
Palisade, Minnesota and McGregor, Minnesota (USA).
For tow roads there were two east/west roads that were half mile apart each four miles long.
Crisscrossing the two parallel east/west roads were three north/south roads each a mile and a half long.
The club pilots named it, "The Black Hole." It put us into the third dimension for many XC flights.
The Black Hole. Minnesota.JPG
The Black Hole. Minnesota.JPG (42.03 KiB) Viewed 4074 times

Some days even though we had a lot of roads we would find ourselves towing up between cloud Streets.
With winds 10 to 15 MPH the thermals would line up like soldiers and form a line of clouds that indicated
the line of lift that we wanted to follow down wind.
As luck would have it many times the roads were not under the cloud streets but under the clear sinky air
between the cloud streets.
Some days we sunk out after several tows then we would tell the tow driver to tow us up and take a left
at the next intersection. Before the driver turned the corner we would have to fly to the right side of the
tow road in anticipation of the slack we would get when the tow vehicle turned left. That turn would
get us under the cloud street where we would release the tow line and leave, "The Black Hole."
In the drawing below the squiggly line is the approximate flight path for the glider that would make the
90°tow-up work.
Once a thermal has been generated you have to find it.
Car tows HG under a cloud street..JPG
Car tows HG under a cloud street..JPG (17.31 KiB) Viewed 4074 times
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Re: Thermal generating

Postby Craig Muhonen » Wed Nov 30, 2022 10:52 am

From my crawlspace perspective.
Crazy questions;
If smoke is released in the top third of a thermal, would it "show" the thermal and stay inside?
Are there drones equipped with temperature sensors
that could relay back a separate "differential", to the pilot's "special head set" like a variometer ?

Here's an analogy from my surfboards point of view;

As I easily paddled, not "thrashed", into a wave on my 9' 7" Jacobs, the board which was awkward to "ground handle", seemed to become weightless and as soon as I started carving a turn I could generate speed, I could do, "no paddle take offs" just as easily,
plus I could put all my body weight on the nose and the "heavy" board retained it's weightless feeling and I could still steer, it's almost like the board became invisible.
The board had good mass to it, and was shaped to maximize these quality's.
Everybody knew exactly who we were when we were driving. Same same for Hang Gliders.
A badge of honor. (that PG could never have}

Hmm....isn't a Hang Glider Wing the exact same thing,
and was developed
to "surf" the sky and just carve long turns and "run the nose", and then be stored on top. :thumbup:

That's where the fun is at.
it becomes weightless at the moment it is launched, but has good mass to allow it to go fast or slow with equal control.
In My mind I see the 1980 shape and mass of those hang gliders as the epidemy of a "performance glider".

Here's an adage that might apply;
A nose heavy air'plane' is hard to fly but a tail heavy airplane, flies once.

1972-1980, 8 years at low dollars, and Lloyds of London,
but maximum efficiency and pure fun. :lol: (which is key).

Soaring is soaring but,
these strong hand made gliders also had the ability to do "dead stick" slow landings (even in trees) with precision.
Being able to always fly your aircraft, 'ALL' the way to a crash landing is a learned trait that HG has developed. bottom line, "Aircraft".

1980-2022, 44 years at high dollars with only small increases in performance but big increases in,
"here's your next performance glider to buy", (from just a few and which are harder to land).
or "here is a great club that you can join for just a few dollars". :yawn: (boring)

2022 onward;
Maybe high tek additions to existing hang gliders (topless excluded)
which make them easier to land on a dime.
couldn't the battens and spoilers (David Cronk used them early) be made to be "electronically controllable"?
couldn't the "pilot pod" have a usable tail like a Hawk?
Sky divers have a fun "wind machine" to train new pilots in, HG could develop a better one that was way more fun, and portable.

I think being able to land in a small space is PG's big advantage but at great cost as to penetrating speed, and then the asymmetrical stall.
Packable or not, the mass and shape of the wing, like the Longboard, makes it cool.


Sometimes you gotta' push the stick forward while you're lookn' at the ground
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