[philfly]

I live near Brighton Ontario and after 2 seasons of powered flight am really enjoying learning to use my Radian glider. I have been wondering if it is possible to catch a thermal in the winter time, and if so, what conditions or signs should I look for? Any advice would be helpful. Phil

[Giodog2000]

Hi Phil,
Yes of course you can find lift (thermals) in winter. You are basically looking for the same things.
Look for days with Cumulus formation (unstable air) and days where temperature difference from morning to afternoon is high. EX: -15 morning ,
-2 afternoon.

You might not find as much as in summer , but you can definitely fly and once in a while get lucky and catch that winter thermal

I'll be flying for sure , so good luck and report back ....

Gio
crazycanuckgliders.ca

[philfly]

Well, that's great news Gio. Thanks! I have a transmitter glove for the hands so I'll be going out and hope to catch a thermal. I'm also interested in trying slope soaring. I'm in the Brighton area but don't know of any accessible, open hills. Might you have a line on that?
Thanks for your help,
Phil

[FabFlight]

The Radian is a great platform for winter.

Replace the plastic spinner by an aluminium one. Warm your batteries by placing them in your pant's pockets. Clear the snow/ice that packs inside/behind the spinner.

Personnaly, I don't recall seing cumulus in winter. The sky is either clear or mushy.

Here's what I do.

On a warmer day with very low winds, find a large deserted parking, cleared of snow. The sun warming the ashphalt creates light lift that keeps you aloft at around 40 meters for a pretty long time. Did a 30 minutes flight once. Watch out for these darn light posts. I don't trust my depth judgment anymore

Two years ago I flew once or twice a month, through out winter. A shield over your radio and hands really helps tolerate the subzero conditions. HobbyKing used to sell one with openings on the sides for the hands and a clear window in the front.

[FabFlight]

Transmitter muff
http://hobbyking.com/hobbyking/store...uff_Black.html

[Giodog2000]

Originally Posted by FabFlight

Personnaly, I don't recall seing cumulus in winter. The sky is either clear or mushy.

Fab,

To keep it simple...there are many kinds of Cumulus. So I bet you already saw some in winter but never realized it was a Cumulus. And I bet in Brington Ontario, right beside Lake Ontario, He can see some cumulus on a hot winter day.

-Cumulus
-Stratocumulus
-Altocumulus

Oh and maybe you can watch this video of a typical winter day in Alaska
Watch at around 0.45sec.....
https://www.youtube.com/watch?v=xlDi2Apw_RA

[mjohnson]

Whether or not you will encounter lift on any given day will depend on the lapse rate of the airmass at the time. A good but kind of dry explanation:

https://en.wikipedia.org/wiki/Lapse_rate

This is all well and good when dealing with full scale thermal soaring as they are usually dealing with altitudes of over 1000 ft. We on the other hand are usually dealing with altitudes of less than 1000 ft. Therein lies the rub. The mechanics and dynamics of thermal activity under 1000 ft are basically the same but on a micro scale. The presence of cumulus clouds CAN be a good indication of the lapse rate in the upper (above 1000 ft) airmass. Usually in a given cubic kilometer of low level airmass there is upgoing (lift) and downgoing (sink) air.

There are two types of lift that we as modellers deal with. First is orographic or mechanical lift. This is commonly called slope soaring. When a moving air mass encounters any type of rising structure (hill, large buildings and yes even a tree line) the structure forces the air up and generates lift. The strongest lift is typically just in front of the crest of the structure and extends vertically from there. As long as the wind is blowing you can use this lift all day to stay aloft. The other type of lift is called convective lift. This is where through convective heating of a local area causes the lapse rate to become modified. In other words the local air is heated to a warmer temperature compared to the surrounding air. The modified air starts to rise through expansion and creates lift. Voila...a thermal. As we deal with the micro climate I am going to go out on a limb and call it a "heat bubble" but to be sure it is still a mini thermal. These "bubbles" can be caused by, as the previous poster stated, by a warmed parking lot but there are other sources as well. Look for anything on the ground that will cause a difference in temperature. Open ponds of open water can create a difference. A row of houses or warmed buildings can cause a difference. Just do not fly over the buildings or structures but if there is even the slightest of breeze fly downwind of these structures and the "bubbles" should still be there. There are also lots of other places to find a difference in temperature. A task for you to find out! Once again, look for something that will cause a difference in temperature.

You can also use a combination of both orographic and convective lift. If a small mass of air has been warmed but not quite to the point of rising and there is a bit of a breeze, a row of trees can cause the warmer air to start to rise. We locally call this "popping lift". That kind of lift typically does not last very long as the "bubble" cools rapidly but if you go back to the same spot you can generally find another bit of "popping" lift.

There is a lot more to soaring than meets the eye. All the top soaring competitors can look at that cubic km of airspace and dependably predict where the lift will be. This is an aquired talent that comes with years of practice.

Look at is as being like fishing. You know they are there but sometimes it takes all day to catch one!! They are there though.

Cheers

Murray

[FabFlight]

Originally Posted by Giodog2000

Oh and maybe you can watch this video of a typical winter day in Alaska
Watch at around 0.45sec.....
https://www.youtube.com/watch?v=xlDi2Apw_RA

Description says:
Cumulus Clouds over Phoenix, Arizona.
Music by: Alaska in Winter - Balkan Lowrider Anthem

[Giodog2000]

Originally Posted by FabFlight

Description says:
Cumulus Clouds over Phoenix, Arizona.
Music by: Alaska in Winter - Balkan Lowrider Anthem

lol ok ok.

[mark B]

Hi Phil:

I'd like to try some local slope soaring too. have you found or heard of any sites?

Anyone:
Know of a decent area from Peterborough to Kingston (Ideally the Campbellford-Stirling area)?

Better yet, if you're going slope soaring in the area, I'd love to tag along with my 2m glider.

Thanks, Mark