Best performing Vario?

At 16:28 29 September 2012, AGL wrote:

One good reason is fiberglass construction, modern airfoils, and
heavy=20
gliders. Fly slowly at 1-26 or K-6 speeds, and even a pellet vario
can=20
work well. Blast through the thermal at 90-100 knots, full of water ...
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to=20
=20

So, the question becomes, what software is best for what conditions?
This
=
post assumes that the varios input to the software shows true lift
without
=
gusts etc.

The PC SeeYou stats showed that on 200 km of distance yesterday, with
overd=
eveloped cloudbases as low as 2500 ft AGL, average climbs were as low as
1
=
knot or zero, getting blown home on wind. Most "circles" showed lift and
4=
knot gusts at opposite sides of the circle, and sink everywhere else.
Mov=
ing to one direction to the other resulted in the same thing with a
differe=
nt set of short term lift bubbles. That's trying both slow 45 degree
banks=
, or back and forth sniffing in the bubbly area that had more lift than
sin=
k. When you're that low you have to do what you have to do.

Other people's flights on the OLC that day showed pretty mush the same
cond=
itions/results, but I didn't see anyone doing the "sniff around" method.

Sometimes you just have to fly around a bubbly area that has more lift
than=
sink, and a 1 minute average lift option on a very weak bubble day would
h=
elp. That's about the size of a "sniff around" area, which isn't a
thermal=
at all even if there is more lift than sink. "Last thermal" stats on
soft=
ware I've used/seen so far stops working as soon as you go straight for
any=
length of time.

So, what I'm saying is that the software development and discussion seems
t=
o be optimized for classic Texas lift silos on nice days, not for
overdevel=
oped low weak days when you'r relying on the circulation from latent heat
o=
f liquidization just under cloudbase.

The suggested XCSOAR thermal assistant screen
http://bugs.xcsoar.org/raw-at=
tachment/ticket/2148/modifiedthermalassistant.png would work well for
these=
conditions if it would show a one mile sniffing area with bubble
clusters,=
even if you're flying back and forth rather than circling. The outer
ring=
would still work for the classic thermal situation.

So, I would suggest that Tobias' proposal works for more situations than
An=
drzej's objection, since not all of us can assume classic thermal silos
of
=
lift on non-classic lift days.


Try an LX8000 with track set to display vario (colour coding). Great for
sniffing around as you describe, and thermals that shift as you climb.

Mike

On Sat, 29 Sep 2012 20:31:15 +0000, Michael Clarke wrote:

Try an LX8000 with track set to display vario (colour coding). Great for
sniffing around as you describe, and thermals that shift as you climb.

Agreed about the colour coded track. LK8000 uses the same colour coding
scheme for its track display. I find this is more useful for sniffing
round a thermal than the thermal finder, which I've turned off. As my
normal thermalling technique uses the vario audio to re-center every
circle I don't bother looking at LK8000 once I've found the thermal,
though I may occasionally glance at its thermalling history bar.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

not sure what color profile the LX8000 is using, but XCSoar also shows the track color coded to the amount of lift. you can choose between two different color sets (including the Naviter/SeeYou color profile) and a third one that color codes the altitude instead of the lift.

basically that means that there are two types of thermal assistants in XCSoar. the traditional method with the color coded track on the map and the additional thermal assistant gauge that obviously works best for perfect round thermals and a good vario connected to it.

I personally have used the gauge for about two years now with my XCSoar device connected to a Flarm, that only outputs the barometric altitude and no direct vario signal, and I have to say that even with this small setup I am still impressed on how well the assistant already works. I can't even imagine how perfect it would work when connected to the "best performing vario" that this thread was originally about.