SeeYou wind calculations

Here in Hood River, Oregon, USA, we usually have lots of wind and
sometimes when I view the flights on SeeYou, it shows the wind very
accurately and sometimes it doesn't. It doesn't seem to matter if
there is a lot of circling on the flight or not. Sometimes when I
first look at the flight it doesn't show any wind and then when I view
the flight again, later there is wind shown. Has anybody else had
this problem? Does anybody have a suggestion for a fix?

Thanks

Hi Gary,

What GPS or flight computer is the PDA and SeeYou Mobile receiving data
from?

Paul Remde

"GARY BOGGS CFIG" wrote in message
...
Here in Hood River, Oregon, USA, we usually have lots of wind and
sometimes when I view the flights on SeeYou, it shows the wind very
accurately and sometimes it doesn't. It doesn't seem to matter if
there is a lot of circling on the flight or not. Sometimes when I
first look at the flight it doesn't show any wind and then when I view
the flight again, later there is wind shown. Has anybody else had
this problem? Does anybody have a suggestion for a fix?

Thanks

On Sep 27, 11:58*am, "Paul Remde" wrote:
Hi Gary,

What GPS or flight computer is the PDA and SeeYou Mobile receiving data
from?

Paul Remde

"GARY BOGGS CFIG" wrote in ...



Here in Hood River, Oregon, USA, we usually have lots of wind and
sometimes when I view the flights on SeeYou, it shows the wind very
accurately and sometimes it doesn't. *It doesn't seem to matter if
there is a lot of circling on the flight or not. *Sometimes when I
first look at the flight it doesn't show any wind and then when I view
the flight again, later there is wind shown. *Has anybody else had
this problem? *Does anybody have a suggestion for a fix?

Thanks

More like how is the .IGC file created? e.g. is it a file from a
Cambridge 302 or is it created by SeeYou Mobile. In the later case
there is TAS data in IGC file that is used by SeeYou to calculate wind
without circling. If you have plain non-TAS enhanced IGC data and
little circling then by definition SeeYou is going to have a tough
time guestimating the wind. Even if there is TAS data in the file and
sufficient heading change to calculate wind without circling it does
seem that SeeYou needs to be run forward in time to pick up that data.
If you carefully advance up to any point I expect SeeYou winds to be
consistent within reason. If not you should send a sample file to
Naviter and describe how to reproduce the problem.

Wind calculated in flight even by the same device as is creating the
IGC file may behave differently from what you see post flight. The in
flight calcs may use TAS data but that may not be available to SeeYou,
and if it is it may be at a much coarser sample rate.


Very coarse sample rates in the IGC file even when circling can also
be a problem. Even the dumbest PDA is reading GPS data many times per
second. If that is reduced to once every 10 or so seconds it can
change the wind calcs.

So what data exactly are you driving SeeYou with?
Darryl

On Sep 27, 4:38*pm, Darryl Ramm wrote:
On Sep 27, 11:58*am, "Paul Remde" wrote:





Hi Gary,

What GPS or flight computer is the PDA and SeeYou Mobile receiving data
from?

Paul Remde

"GARY BOGGS CFIG" wrote in ...

Here in Hood River, Oregon, USA, we usually have lots of wind and
sometimes when I view the flights on SeeYou, it shows the wind very
accurately and sometimes it doesn't. *It doesn't seem to matter if
there is a lot of circling on the flight or not. *Sometimes when I
first look at the flight it doesn't show any wind and then when I view
the flight again, later there is wind shown. *Has anybody else had
this problem? *Does anybody have a suggestion for a fix?

Thanks

More like how is the .IGC file created? e.g. is it a file from a
Cambridge 302 or is it created by SeeYou Mobile. In the later case
there is TAS data in IGC file that is used by SeeYou to calculate wind
without circling. If you have plain non-TAS enhanced IGC data and
little circling then by definition SeeYou is going to have a tough
time guestimating the wind. Even if there is TAS data in the file and
sufficient heading change to calculate wind without circling it does
seem that SeeYou needs to be run forward in time to pick up that data.
If you carefully advance up to any point I expect SeeYou winds to be
consistent within reason. If not you should send a sample file to
Naviter and describe how to reproduce the problem.

Wind calculated in flight even by the same device as is creating the
IGC file may behave differently from what you see post flight. The in
flight calcs may use TAS data but that may not be available to SeeYou,
and if it is it may be at a much coarser sample rate.

Very coarse sample rates in the IGC file even when circling can also
be a problem. Even the dumbest PDA is reading GPS data many times per
second. If that is reduced to once every 10 or so seconds it can
change the wind calcs.

So what data exactly are you driving SeeYou with?
Darryl

On Sep 27, 4:38*pm, Darryl Ramm wrote:
[snip]
Darryl

What I was trying to add to my own post was...

And to be clear in my example the IGC file created by SeeYou Mobile
will contain TAS data if fed by say a Cambridge 302 which outputs TAS
data in the NMEA stream. Obviously if you feed SeeYou Mobile from pure
GPS source you don't get this. Another example is say an SN10 which
although it uses TAS for internal wind calculations does not pass it
to an external PDA for capturing to the PDA generated (unofficial) IGC
file. (Why that is escapes me.) It might capture the TAS or wind data
in it's own (unofficial) IGC file, I'm note sure. The point is the
exact providence of your data has a huge effect on the wind
calculations. For these reasons I'll often capture an official IGC
file in my C302MG (needed for OLC with a motorglider) but use the
SeeYou Mobile generated IGC file at 1 sec sample rate for analysis
because it captures TAS info for better wind calculations by SeeYou.

Darryl

I am getting my .igc file from a Colibri, and my sample rate is every
two seconds. I also removed SeeYou and reloaded a fresh version but
still show no winds sometimes.

On Sep 28, 7:35*am, GARY BOGGS CFIG wrote:
I am getting my .igc file from a Colibri, and my sample rate is every
two seconds. *I also removed SeeYou and reloaded a fresh version but
still show no winds sometimes.

The Collibri IGC file contains no TAS data. If as you say you don't
circle much SeeYou has no data to us to calculate a wind. I'd say
likely working as designed. Play the trace forward through a thermal
for the most accurate then current wind.

Darryl