Winter Thermal Cross-Country

Stefan wrote:
wrote:

have already enjoyed some wonderful thermals in the southwest (USA).
But I think I've had only a few that averaged 10+ knots for more than a
few thousand feet. (I've had a couple that averaged ~8 knots from 1500'


Are you aware that here where I fly the average thermal is between 1 and
4 knots and the average working altitude something like 1500 feet? (If I
get a 30 knotter for a couple of thousand feet, then it's usually within
a cloud.) But nevertheless, we routinely fly 300 km and more.

We feel for you 8^)

Best one I've hooked was 17.5 knots (measured from the IGC file) from
9000 feet (2500 AGL) to 18000 feet, east of Mono Lake on the
California/Nevada border. I've done a few turns here and there at 20+
knots, but the stronger days average 10 to 12 knots, decent days 7 to
10, and weaker days 5 to 7 knots. If it is weaker than that, you
usually can't get high enough to clear the ridges, and there are lots of
places where you don't want to risk being low. We tend to stay close to
home if we can't climb to 12000 feet.

Marc

Yes, Stefan, but you don't have several miles of 5 knot sink in between
your thermals either!

I was noting that at the start of our winter and the traditional end of
the thermal soaring season in Arizona, we had a couple of 300 km plus
flights the other day. I was wondering how many places in the world
have good late fall/winter thermals.

Lots of places (includng Chile) have spectacular conditions during
summer, but I was curious how many folks enjoy winter thermals?

I was driving in Idaho last February in snow showers and there were
snow devils that looked just like our summer dust devils. I suspect
that winter thermals might be more common than we think.

Mike

Mike the Strike wrote:
.../..

I was driving in Idaho last February in snow showers and there were
snow devils that looked just like our summer dust devils. I suspect
that winter thermals might be more common than we think.

Slightly off topic, but....

Many years ago I wanted to check the still air trim of a F1A towline
glider, so when I woke up to see still air and a couple of inches of
snow I thought the time had come, grabbed the model and headed for the
park for a quick before work session. Wrongo: there were thermals a
plenty over the snow. It was fun, but the still air trimming session
didn't happen.

The park was Clapham Common. We don't get much snow in London, hence the
excitement.

--
martin@ | Martin Gregorie
gregorie. |
org | Zappa fan & glider pilot