Wind information

Throughout this season I've flown with several friends that use
different instruments that calculate wind information while in flight.

I use a GPS driving a PDA running LK8000 (I don't use the new true
wind function). Ron uses an SN-10, Dan uses a PDA running Seeyou and
getting wind information via GPS and the Tasman FP module, Brian uses
an iPAQ 310 running Seeyou and using only GPS wind (internal GPS
chip).

My observations are that generally we are all within 2 to 7 knots and
5 to 15 degrees of speed and direction off when we report to each
other what we are seeing at that moment. The guys using GPS only have
the widest spread and the guys using pitot/static/GPS seem to be
closer and I feel more accurate. However even with my GPS driven wind
I still feel fairly confident that it is giving me very useful
information. I.E. coming back off the flats in Eastern WA heading into
a strong headwind it was nice to know the ridge up ahead was going to
give me ridge lift when I got to it.

I also think that since when we report the wind info to each other, we
are spread out across a large area of sky and the winds could very
well be different, so maybe there isn't that large of a difference due
to calculation methods after all. In the foothills/mountains there can
be large local airmass difference due to orographic, local flow,
valley flow, etc..............

Anyone have any thoughts on this foggy morning rambling?

Brad

I use a PNA running LK8000 and also an SN10. Sometimes there are quite wide
differences, but generally the two agree fairly well, within 10 deg and 2/3
kts.
Dave


At 16:25 02 October 2010, Brad wrote:
Throughout this season I've flown with several friends that use
different instruments that calculate wind information while in flight.

I use a GPS driving a PDA running LK8000 (I don't use the new true
wind function). Ron uses an SN-10, Dan uses a PDA running Seeyou and
getting wind information via GPS and the Tasman FP module, Brian uses
an iPAQ 310 running Seeyou and using only GPS wind (internal GPS
chip).

My observations are that generally we are all within 2 to 7 knots and
5 to 15 degrees of speed and direction off when we report to each
other what we are seeing at that moment. The guys using GPS only have
the widest spread and the guys using pitot/static/GPS seem to be
closer and I feel more accurate. However even with my GPS driven wind
I still feel fairly confident that it is giving me very useful
information. I.E. coming back off the flats in Eastern WA heading into
a strong headwind it was nice to know the ridge up ahead was going to
give me ridge lift when I got to it.

I also think that since when we report the wind info to each other, we
are spread out across a large area of sky and the winds could very
well be different, so maybe there isn't that large of a difference due
to calculation methods after all. In the foothills/mountains there can
be large local airmass difference due to orographic, local flow,
valley flow, etc..............

Anyone have any thoughts on this foggy morning rambling?

Brad

On Oct 2, 10:55*am, David Salmon wrote:
I use a PNA running LK8000 and also an SN10. Sometimes there are quite wide
differences, but generally the two agree fairly well, within 10 deg and 2/3
kts.
Dave

At 16:25 02 October 2010, Brad wrote:

Throughout this season I've flown with several friends that use
different instruments that calculate wind information while in flight.

I use a GPS driving a PDA running LK8000 (I don't use the new true
wind function). Ron uses an SN-10, Dan uses a PDA running Seeyou and
getting wind information via GPS and the Tasman FP module, Brian uses
an iPAQ 310 running Seeyou and using only GPS wind (internal GPS
chip).

My observations are that generally we are all within 2 to 7 knots and
5 to 15 degrees of speed and direction off when we report to each
other what we are seeing at that moment. The guys using GPS only have
the widest spread and the guys using pitot/static/GPS seem to be
closer and I feel more accurate. However even with my GPS driven wind
I still feel fairly confident that it is giving me very useful
information. I.E. coming back off the flats in Eastern WA heading into
a strong headwind it was nice to know the ridge up ahead was going to
give me ridge lift when I got to it.

I also think that since when we report the wind info to each other, we
are spread out across a large area of sky and the winds could very
well be different, so maybe there isn't that large of a difference due
to calculation methods after all. In the foothills/mountains there can
be large local airmass difference due to orographic, local flow,
valley flow, etc..............

Anyone have any thoughts on this foggy morning rambling?

Brad

david,
which PNA?

At 19:15 02 October 2010, brianDG303 wrote:
On Oct 2, 10:55=A0am, David Salmon wrote:
I use a PNA running LK8000 and also an SN10. Sometimes there are quite
wi=
de
differences, but generally the two agree fairly well, within 10 deg
and
2=
/3
kts.
Dave

At 16:25 02 October 2010, Brad wrote:

Throughout this season I've flown with several friends that use
different instruments that calculate wind information while in
flight.

I use a GPS driving a PDA running LK8000 (I don't use the new true
wind function). Ron uses an SN-10, Dan uses a PDA running Seeyou and
getting wind information via GPS and the Tasman FP module, Brian uses
an iPAQ 310 running Seeyou and using only GPS wind (internal GPS
chip).

My observations are that generally we are all within 2 to 7 knots and
5 to 15 degrees of speed and direction off when we report to each
other what we are seeing at that moment. The guys using GPS only have
the widest spread and the guys using pitot/static/GPS seem to be
closer and I feel more accurate. However even with my GPS driven wind
I still feel fairly confident that it is giving me very useful
information. I.E. coming back off the flats in Eastern WA heading
into
a strong headwind it was nice to know the ridge up ahead was going to
give me ridge lift when I got to it.

I also think that since when we report the wind info to each other,
we
are spread out across a large area of sky and the winds could very
well be different, so maybe there isn't that large of a difference
due
to calculation methods after all. In the foothills/mountains there
can
be large local airmass difference due to orographic, local flow,
valley flow, etc..............

Anyone have any thoughts on this foggy morning rambling?

Brad

david,
which PNA?

An iPAQ 314, though opinion is tending towards a Mio M400 for better
visibility in sunlight. Not much of a problem in the UK these days.
The iPAQ internal gps is not very good in a glider, gives some odd
results at times, so I use a Holux BT gps with.
Dave

Anyone have any thoughts on this foggy morning rambling?

Brad

It's OK, it happens to all old people. Take your Metamucial and go for
a walk.
R

On Oct 3, 8:28*am, hretting wrote:
Anyone have any thoughts on this foggy morning rambling?

Brad

It's OK, it happens to all old people. Take your Metamucial and go for
a walk.
R

geez, no wonder I don't support the youth in soaring movement, unless
the movement is a metamucial induced one on top of this guys head!

Brad

Brad, I thought your come back was funny and I certainly deserve it.

What I get from your opening thread is perhaps your reluctance to
trust the wind information you are seeing or you are looking for
supporting information that would increase your trust in the
information.
Transitioning to ridge would require accurate wind information, but
you write you do this without fear all the time.
If you would elaborate a little more on what you are thinking
regarding wind data , I'm sure others have helpful input and comments.
Myself , operating a 302 with a CAI M-25 backup...they become accurate
as long as I thermal and slowly diverge / degrade with long stretches
of glides. A few turns and I am amaze how quickly they recapture the
wind. I was able to run trials base on observation of smoke coming off
the burning sugarcane fields and learn my instrument.
R

On Oct 3, 10:44*am, hretting wrote:
Brad, I thought your come back was funny and I certainly deserve it.

What I get from your opening thread is perhaps your reluctance to
trust the wind information you are seeing or you are looking for
supporting information that would increase your trust in the
information.
Transitioning to ridge would require accurate wind information, but
you write you do this without fear all the time.
If you would elaborate a little more on what you are thinking
regarding wind data , I'm sure others have helpful input and comments.
Myself , operating a 302 with a CAI M-25 backup...they become accurate
as long as I thermal and slowly diverge / degrade with long stretches
of glides. A few turns and I am amaze how quickly they recapture the
wind. I was able to run trials base on observation of smoke coming off
the burning sugarcane fields and learn my instrument.
R

Hi,

Well, I did delete it after I had my morning coffee................. I
sure had a laugh when I hit send!

To your question:

I do feel confident that the wind information is reliable enough to
use within a certain amount of time/airspace. What I mean by that is
since I only get wind info from circling (with my set-up) it is good
only for a certain amount of time until I start circling again. So, If
I climb up and get wind info X, then start a long glide the wind could
be different when I finish my glide and I'll not know what it is until
I start circling again and get a new fix. Probably not a big deal when
I think about it.

So actually it looks like we are similar in our thoughts on this!

I am an avid observer of all wind indicators (learned from my years as
a hang glider pilot).

And...........I actually do down a few psylliam caps every night
before bed, it does help......

Brad

In general I find all wind calculations appear to be more accurate
when I like what they say, and less accurate when I don't like what
they are telling me.

A grain of salt........

;-)

Bob

On 10/3/2010 11:09 AM, Brad wrote:
On Oct 3, 10:44 am, wrote:

Brad, I thought your come back was funny and I certainly deserve it.

What I get from your opening thread is perhaps your reluctance to
trust the wind information you are seeing or you are looking for
supporting information that would increase your trust in the
information.
Transitioning to ridge would require accurate wind information, but
you write you do this without fear all the time.
If you would elaborate a little more on what you are thinking
regarding wind data , I'm sure others have helpful input and comments.
Myself , operating a 302 with a CAI M-25 backup...they become accurate
as long as I thermal and slowly diverge / degrade with long stretches
of glides. A few turns and I am amaze how quickly they recapture the
wind. I was able to run trials base on observation of smoke coming off
the burning sugarcane fields and learn my instrument.
R
I do feel confident that the wind information is reliable enough to
use within a certain amount of time/airspace. What I mean by that is
since I only get wind info from circling (with my set-up) it is good
only for a certain amount of time until I start circling again. So, If
I climb up and get wind info X, then start a long glide the wind could
be different when I finish my glide and I'll not know what it is until
I start circling again and get a new fix. Probably not a big deal when
I think about it.

It could be a big deal if you are ridge flying, or flying in the
mountains (that's' _in_ not _over_), or wave is present but not strongly
established. Under those conditions, the wind can change significantly
from where you last circled due to valley flows, mountain peaks/ridges
diverting the wind, or wave dipping down into the convection layer (or
coming and going as the speed, direction, and air mass change).

My experience is wind derived from circling is adequate for relatively
open areas, like the Columbia basin in Eastern Washington state, but
"current headwind" derived from an air-data vario like the my 302 is
very useful in the ridge/mountain/wave situations. And, of course,
during long glides (like a final glide), where the glider sinks
thousands of feet lower than the altitudes I at which I was circling and
getting wind measurements.

If wind is important to you, spend the money for an air-data instrument.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm http://tinyurl.com/yb3xywl
- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz