SN-10 vs CAI 302

[Frank[_1_]]

Hi,

I have been using a SN-10B/Volkslogger combination in my LS-4 for the
last 5 years and have loved it. However, I just acquired a glider with
a CAI-302/PDA combination and am contemplating swapping the systems
before selling my LS-4.

I like the presumed flexibiity of taking the PDA with me at the end of
the day, having the flight log on the SD card as opposed to having to
upload to a laptop, and having the option of running different flight
software on the PDA. I also like the idea of having it with me at the
pilot's meeting and being able to set up the task and/or do what-ifs
for AATs without having to be at the glider.

However, I'm not sure about giving up the SN-10's simplicity and its
superior (I think) wind calculations.

At the risk of starting a religious war, I would like input on the
strengths/weaknesses of the CAI-302/PDA (running GPS Glide Navigator II
or similar) for competition use as compared to the SN-10, especially
from those of you who have used both for competitions.

TIA,

Frank

[Udo]

Frank,
keep both.
I fly an Lnav/GPSnav with a 1550 and a 302A with a 39xx as a backup.
Udo

Frank wrote:
> Hi,
>
> I have been using a SN-10B/Volkslogger combination in my LS-4 for the
> last 5 years and have loved it. However, I just acquired a glider with
> a CAI-302/PDA combination and am contemplating swapping the systems
> before selling my LS-4.
>
> I like the presumed flexibiity of taking the PDA with me at the end of
> the day, having the flight log on the SD card as opposed to having to
> upload to a laptop, and having the option of running different flight
> software on the PDA. I also like the idea of having it with me at the
> pilot's meeting and being able to set up the task and/or do what-ifs
> for AATs without having to be at the glider.
>
> However, I'm not sure about giving up the SN-10's simplicity and its
> superior (I think) wind calculations.
>
> At the risk of starting a religious war, I would like input on the
> strengths/weaknesses of the CAI-302/PDA (running GPS Glide Navigator II
> or similar) for competition use as compared to the SN-10, especially
> from those of you who have used both for competitions.
>
> TIA,
>
> Frank

[Frank[_1_]]

Udo,

Cant do that - have to have something in the glider when I sell it ;-)

Frank

Udo wrote:
> Frank,
> keep both.
> I fly an Lnav/GPSnav with a 1550 and a 302A with a 39xx as a backup.
> Udo
>
> Frank wrote:
> > Hi,
> >
> > I have been using a SN-10B/Volkslogger combination in my LS-4 for the
> > last 5 years and have loved it. However, I just acquired a glider with
> > a CAI-302/PDA combination and am contemplating swapping the systems
> > before selling my LS-4.
> >
> > I like the presumed flexibiity of taking the PDA with me at the end of
> > the day, having the flight log on the SD card as opposed to having to
> > upload to a laptop, and having the option of running different flight
> > software on the PDA. I also like the idea of having it with me at the
> > pilot's meeting and being able to set up the task and/or do what-ifs
> > for AATs without having to be at the glider.
> >
> > However, I'm not sure about giving up the SN-10's simplicity and its
> > superior (I think) wind calculations.
> >
> > At the risk of starting a religious war, I would like input on the
> > strengths/weaknesses of the CAI-302/PDA (running GPS Glide Navigator II
> > or similar) for competition use as compared to the SN-10, especially
> > from those of you who have used both for competitions.
> >
> > TIA,
> >
> > Frank

[[email protected]]

Buy a Garmin GPS 16-HVS ($129 us) for the SN-10 and keep the
Volkslogger to run the PDA.

That will give you an easy way to download flights and a backup logger.

Frank wrote:
> Udo,
>
> Cant do that - have to have something in the glider when I sell it ;-)
>
> Frank
>
> Udo wrote:
> > Frank,
> > keep both.
> > I fly an Lnav/GPSnav with a 1550 and a 302A with a 39xx as a backup.
> > Udo
> >
> > Frank wrote:
> > > Hi,
> > >
> > > I have been using a SN-10B/Volkslogger combination in my LS-4 for the
> > > last 5 years and have loved it. However, I just acquired a glider with
> > > a CAI-302/PDA combination and am contemplating swapping the systems
> > > before selling my LS-4.
> > >
> > > I like the presumed flexibiity of taking the PDA with me at the end of
> > > the day, having the flight log on the SD card as opposed to having to
> > > upload to a laptop, and having the option of running different flight
> > > software on the PDA. I also like the idea of having it with me at the
> > > pilot's meeting and being able to set up the task and/or do what-ifs
> > > for AATs without having to be at the glider.
> > >
> > > However, I'm not sure about giving up the SN-10's simplicity and its
> > > superior (I think) wind calculations.
> > >
> > > At the risk of starting a religious war, I would like input on the
> > > strengths/weaknesses of the CAI-302/PDA (running GPS Glide Navigator II
> > > or similar) for competition use as compared to the SN-10, especially
> > > from those of you who have used both for competitions.
> > >
> > > TIA,
> > >
> > > Frank

[Mark Hawkins]

Hi Frank,
Why do you think the SN10's wind calcs are that much more (if any)
superior than the 302's? I've never seen anything empirical comparing
them. I don't think I've ever read anything even written that was
hear-say. I have seen a 302 in action and it's wind calcs seem pretty
good to me. You also can't beat the size; good vario, certified logger
and GPS all in one nice, small package.

However, the suggestion made to split the volkslogger from the sn10 and
thus have a backup system does have merit. As I said at Fairfield, the
SN10 can also now drive a PDA passing the GPS data through and adding
other info to it.

Just my 2 cents

-Mark
Frank wrote:
> Hi,
>
> I have been using a SN-10B/Volkslogger combination in my LS-4 for the
> last 5 years and have loved it. However, I just acquired a glider with
> a CAI-302/PDA combination and am contemplating swapping the systems
> before selling my LS-4.
>
> I like the presumed flexibiity of taking the PDA with me at the end of
> the day, having the flight log on the SD card as opposed to having to
> upload to a laptop, and having the option of running different flight
> software on the PDA. I also like the idea of having it with me at the
> pilot's meeting and being able to set up the task and/or do what-ifs
> for AATs without having to be at the glider.
>
> However, I'm not sure about giving up the SN-10's simplicity and its
> superior (I think) wind calculations.
>
> At the risk of starting a religious war, I would like input on the
> strengths/weaknesses of the CAI-302/PDA (running GPS Glide Navigator II
> or similar) for competition use as compared to the SN-10, especially
> from those of you who have used both for competitions.
>
> TIA,
>
> Frank

[Thomas Knauff]

Some years ago, I was given a PDA and one of the popular software programs
to add to my SN-10 information.

At first, I thought, Wow, this is really neat!
But after flying with the two systems for awhile, I took stock of what I was
being presented.

There are two kinds of information - interesting and useful. As a
competition pilot, all that "interesting" information is a distraction and
detracts from my soaring performance.

I then wrote down what I need to know (emphasis on "need") at any moment
before, during and after a flight. After doing this, I discovered the ILEC
SN-10 has everything I need in an easy to use, non-distracting, easy to see
display save a few things found on a sectional chart.

So I removed the PDA, (far less distracting) and carry a sectional chart I
never have needed to look at.

I will admit there probably are places in the soaring world a sectional
chart is required and will serve me well. As for the PDA, I prefer to spend
most of my time looking outside the cockpit.

Tom Knauff



"Mark Hawkins" > wrote in message
ups.com...
> Hi Frank,
> Why do you think the SN10's wind calcs are that much more (if any)
> superior than the 302's? I've never seen anything empirical comparing
> them. I don't think I've ever read anything even written that was
> hear-say. I have seen a 302 in action and it's wind calcs seem pretty
> good to me. You also can't beat the size; good vario, certified logger
> and GPS all in one nice, small package.
>
> However, the suggestion made to split the volkslogger from the sn10 and
> thus have a backup system does have merit. As I said at Fairfield, the
> SN10 can also now drive a PDA passing the GPS data through and adding
> other info to it.
>
> Just my 2 cents
>
> -Mark
> Frank wrote:
> > Hi,
> >
> > I have been using a SN-10B/Volkslogger combination in my LS-4 for the
> > last 5 years and have loved it. However, I just acquired a glider with
> > a CAI-302/PDA combination and am contemplating swapping the systems
> > before selling my LS-4.
> >
> > I like the presumed flexibiity of taking the PDA with me at the end of
> > the day, having the flight log on the SD card as opposed to having to
> > upload to a laptop, and having the option of running different flight
> > software on the PDA. I also like the idea of having it with me at the
> > pilot's meeting and being able to set up the task and/or do what-ifs
> > for AATs without having to be at the glider.
> >
> > However, I'm not sure about giving up the SN-10's simplicity and its
> > superior (I think) wind calculations.
> >
> > At the risk of starting a religious war, I would like input on the
> > strengths/weaknesses of the CAI-302/PDA (running GPS Glide Navigator II
> > or similar) for competition use as compared to the SN-10, especially
> > from those of you who have used both for competitions.
> >
> > TIA,
> >
> > Frank
>

[[email protected]]

Frank,
I have flown with both the SN-10 and the 302/PDA combination using
Winpilot in sports class competition. I can't back up my claim with
data, but my impression is that the SN-10 does a better job with wind
and final glide calculations. I believe the PDA with Winpilot has a
far superior moving map, and is a bit easier to enter tasks, but if I
had to choose I'd still go with the SN-10 over the 302/PDA combination.
Happily, I actually now use both. I was able to build a cable and
toggle switch which allows the GPS engine in my 302 feed both my SN-10
and the PDA, plus I have the option of downloading flights either to
the PDA or from the SN-10 to a laptop. I typically use the SN-10 as my
primary navigation and flight data computer and keep the PDA as a
backup. I only turn it on every now and then when I need to see the
moving map.
I'd keep the SN-10.
Clay

[Andy[_1_]]

Frank wrote:
> However, I'm not sure about giving up the SN-10's simplicity and its
> superior (I think) wind calculations.

The SN10 computes the wind and uses it. The 302 just computes wind and
makes it available for use. How the wind estimate is used depends on
what PDA software you run. Some PDA software provides non intuitive
(to put it kindly) task estimates in presence of strong winds.

Andy

[[email protected]]

Andy wrote:
> Frank wrote:
> > However, I'm not sure about giving up the SN-10's simplicity and its
> > superior (I think) wind calculations.
>
> The SN10 computes the wind and uses it. The 302 just computes wind and
> makes it available for use. How the wind estimate is used depends on
> what PDA software you run. Some PDA software provides non intuitive
> (to put it kindly) task estimates in presence of strong winds.
>
> Andy

I have a lot less experience than most of the postings but while I was
renting a variety of gliders it was my opinion that the lease user
friendly was the SN10. I would not want to try to find a landout site
from its moving map and/or indications until I had a few flights under
my belt. I am sure once you have used it for a period of time it is
great.

I use winpilot with the 302 and I find many of the features helpful to
beginning xc pilots. It helps finding thermals and maximizing the lift
when you are in it. Loading multiple tasks and the trace and goto
buttons are also very helpful. Winpilot can get complicated I have a
long way to go before I will be confortable with all its options.

Like a lot of thing in life people like what they get use to.

[Kilo Charlie]

> wrote in message
ups.com...

> I have a lot less experience than most of the postings but while I was
> renting a variety of gliders it was my opinion that the lease user
> friendly was the SN10. I would not want to try to find a landout site
> from its moving map and/or indications until I had a few flights under
> my belt. I am sure once you have used it for a period of time it is
> great.

Interesting since the SN-10 has an entire page devoted to nothing but
closest/nearest landing points. It allows you to order them wrt nearest or
an easy scroll through names for one that you may know you would rather land
at. I use it frequently during racing or other XC and rarely use the map.
It automatically gives distances to the fields and considers the current
winds and Mc setting and also puts in a 150 meter arrival altitude along
with displaying how far over or under a glide to the field you are. I don't
see how something could be much easier to use than that.

Casey Lenox
KC
Phoenix

[Jeremy Zawodny]

Kilo Charlie wrote:
> > wrote in message
> ups.com...
>
> Interesting since the SN-10 has an entire page devoted to nothing but
> closest/nearest landing points. It allows you to order them wrt nearest or
> an easy scroll through names for one that you may know you would rather land
> at. I use it frequently during racing or other XC and rarely use the map.
> It automatically gives distances to the fields and considers the current
> winds and Mc setting and also puts in a 150 meter arrival altitude along
> with displaying how far over or under a glide to the field you are. I don't
> see how something could be much easier to use than that.

Does it include terrain obstructions as well?

Jeremy

[Udo]

I fly with a 1530 and GN II.
I do not have to turn to a different page. The airports and out
landing
fields are displayed at all times. If I have a need for an out
landing
port or field I touch the port on the screen and all relevant info is
displayed,
about that port, including the final glide. I like the one screen one
page display.
Udo






> Interesting since the SN-10 has an entire page devoted to nothing but
> closest/nearest landing points. It allows you to order them wrt nearest or
> an easy scroll through names for one that you may know you would rather land
> at. I use it frequently during racing or other XC and rarely use the map.
> It automatically gives distances to the fields and considers the current
> winds and Mc setting and also puts in a 150 meter arrival altitude along
> with displaying how far over or under a glide to the field you are. I don't
> see how something could be much easier to use than that.
>
> Casey Lenox
> KC
> Phoenix

[Kilo Charlie]

"Jeremy Zawodny" > wrote in message
...

> Does it include terrain obstructions as well?
>
> Jeremy

No but I've always found those quite interesting in concept for glider
pilots.....if you are talking about making it around a mountain on the way
home I'd rather be looking out the window at what's in front of me and not
relying upon an instrument to tell me its there.....head in vs out of the
cockpit idea I guess. Otherwise I can think of nothing that having a moving
map of terrain does to assist me in flying my glider in VFR conditions.

Casey

[Eric Greenwell]

Kilo Charlie wrote:
> "Jeremy Zawodny" > wrote in message
> ...
>
>> Does it include terrain obstructions as well?
>>
>> Jeremy
>
> No but I've always found those quite interesting in concept for glider
> pilots.....if you are talking about making it around a mountain on the way
> home I'd rather be looking out the window at what's in front of me and not
> relying upon an instrument to tell me its there.....head in vs out of the
> cockpit idea I guess. Otherwise I can think of nothing that having a moving
> map

When I fly in the mountains, I find the "obstructions" feature and the
terrain map on SeeYou Mobile quite useful, because looking out the
window towards a landing place I can't see doesn't help me. I know the
mountain(s) is there (that's the usual reason I can't see the landing
place, besides distance), but "can I clear it" isn't something I can
eyeball reliably. The nearest mountain might not be the one that is
blocking me, for example.

Flat lands, low hills, or areas I am totally familiar with - the terrain
feature is of no use to me.

--
Eric Greenwell - Washington State, USA
Change "netto" to "net" to email me directly

"Transponders in Sailplanes" on the Soaring Safety Foundation website
www.soaringsafety.org/prevention/articles.html

"A Guide to Self-launching Sailplane Operation" at www.motorglider.org

[Jeremy Zawodny]

Eric Greenwell wrote:
> Kilo Charlie wrote:
>> "Jeremy Zawodny" > wrote in message
>> ...
>>
>>> Does it include terrain obstructions as well?
>>>
>>> Jeremy
>>
>> No but I've always found those quite interesting in concept for glider
>> pilots.....if you are talking about making it around a mountain on the
>> way home I'd rather be looking out the window at what's in front of me
>> and not relying upon an instrument to tell me its there.....head in vs
>> out of the cockpit idea I guess. Otherwise I can think of nothing
>> that having a moving map
>
> When I fly in the mountains, I find the "obstructions" feature and the
> terrain map on SeeYou Mobile quite useful, because looking out the
> window towards a landing place I can't see doesn't help me. I know the
> mountain(s) is there (that's the usual reason I can't see the landing
> place, besides distance), but "can I clear it" isn't something I can
> eyeball reliably. The nearest mountain might not be the one that is
> blocking me, for example.

Exactly.

On one flight this summer I found myself a bit north of Spooner Lake
trying to decide if I could clear Brockway Pass and make Truckee. I
decided to go for it and after a few miles noticed that SeeYou was
warning me that I'd impact terrain on the way.

Of course, it didn't know that I planned to divert a bit, since the
straight course isn't over the lowest point. But I sure was glad to
know it was thinking of me. :-)

Jeremy

[Kilo Charlie]

"Jeremy Zawodny" > wrote in message
...
> Eric Greenwell wrote:
>> Kilo Charlie wrote:
>>> "Jeremy Zawodny" > wrote in message
>>> ...
>>>
>>>> Does it include terrain obstructions as well?
>>>>
>>>> Jeremy
>>>
>>> No but I've always found those quite interesting in concept for glider
>>> pilots.....if you are talking about making it around a mountain on the
>>> way home I'd rather be looking out the window at what's in front of me
>>> and not relying upon an instrument to tell me its there.....head in vs
>>> out of the cockpit idea I guess. Otherwise I can think of nothing that
>>> having a moving map
>>
>> When I fly in the mountains, I find the "obstructions" feature and the
>> terrain map on SeeYou Mobile quite useful, because looking out the window
>> towards a landing place I can't see doesn't help me. I know the
>> mountain(s) is there (that's the usual reason I can't see the landing
>> place, besides distance), but "can I clear it" isn't something I can
>> eyeball reliably. The nearest mountain might not be the one that is
>> blocking me, for example.
>
> Exactly.
>
> On one flight this summer I found myself a bit north of Spooner Lake
> trying to decide if I could clear Brockway Pass and make Truckee. I
> decided to go for it and after a few miles noticed that SeeYou was warning
> me that I'd impact terrain on the way.
>
> Of course, it didn't know that I planned to divert a bit, since the
> straight course isn't over the lowest point. But I sure was glad to know
> it was thinking of me. :-)
>
> Jeremy

Maybe we're mixing things up a bit. I agree that knowing if I can make a
glide into a landable place is a good thing and the SN-10 does that. I
would still say given that, you should be looking outside to see what
mountains you need to go around in order to get there is a better idea than
looking at an instrument heads down. Also I would not find the instrument
much help unless it could calculate the required deviation from my current
position around the mountain then home. At least for me I would not want to
leave my margins flying in the mountains so thin that I could just clear a
pass.

Finally all of the instrument manufacturers that feature terrain maps state
emphatically that they should NOT be used as terrain avoidance instruments.
My guess is that is due to the inaccuracies of the terrain altitude data.
I'm not willing to bet my life on that.

Casey

[hans]

Flying in mountains I select the next potential landing site quite often
when 50km or more away from the site. For this it is quite helpful to
have the terrain avoidance feature, to select only sites where I don't
have to tunnel through a mountain range.

When I select the next potential landing site, which might be still 50
km away, I might be already below the rims of the surrounding mountain
ranges.


Kilo Charlie schrieb:
> "Jeremy Zawodny" > wrote in message
> ...
>> Eric Greenwell wrote:
>>> Kilo Charlie wrote:
>>>> "Jeremy Zawodny" > wrote in message
>>>> ...
>>>>
>>>>> Does it include terrain obstructions as well?
>>>>>
>>>>> Jeremy
>>>> No but I've always found those quite interesting in concept for glider
>>>> pilots.....if you are talking about making it around a mountain on the
>>>> way home I'd rather be looking out the window at what's in front of me
>>>> and not relying upon an instrument to tell me its there.....head in vs
>>>> out of the cockpit idea I guess. Otherwise I can think of nothing that
>>>> having a moving map
>>> When I fly in the mountains, I find the "obstructions" feature and the
>>> terrain map on SeeYou Mobile quite useful, because looking out the window
>>> towards a landing place I can't see doesn't help me. I know the
>>> mountain(s) is there (that's the usual reason I can't see the landing
>>> place, besides distance), but "can I clear it" isn't something I can
>>> eyeball reliably. The nearest mountain might not be the one that is
>>> blocking me, for example.
>> Exactly.
>>
>> On one flight this summer I found myself a bit north of Spooner Lake
>> trying to decide if I could clear Brockway Pass and make Truckee. I
>> decided to go for it and after a few miles noticed that SeeYou was warning
>> me that I'd impact terrain on the way.
>>
>> Of course, it didn't know that I planned to divert a bit, since the
>> straight course isn't over the lowest point. But I sure was glad to know
>> it was thinking of me. :-)
>>
>> Jeremy
>
> Maybe we're mixing things up a bit. I agree that knowing if I can make a
> glide into a landable place is a good thing and the SN-10 does that. I
> would still say given that, you should be looking outside to see what
> mountains you need to go around in order to get there is a better idea than
> looking at an instrument heads down. Also I would not find the instrument
> much help unless it could calculate the required deviation from my current
> position around the mountain then home. At least for me I would not want to
> leave my margins flying in the mountains so thin that I could just clear a
> pass.
>
> Finally all of the instrument manufacturers that feature terrain maps state
> emphatically that they should NOT be used as terrain avoidance instruments.
> My guess is that is due to the inaccuracies of the terrain altitude data.
> I'm not willing to bet my life on that.
>
> Casey
>
>

[Eric Greenwell]

Kilo Charlie wrote:

> Maybe we're mixing things up a bit. I agree that knowing if I can make a
> glide into a landable place is a good thing and the SN-10 does that. I
> would still say given that, you should be looking outside to see what
> mountains you need to go around in order to get there is a better idea than
> looking at an instrument heads down.

The terrain warning doesn't require you to stare at the PDA, anymore the
Ilec requires you to stare at it. Just glance at it, see the red square
indicating the place where your glide slope is too low, and by how much.
Go back to looking out the window while you decide how to get around or
over the obstacle.

> Also I would not find the instrument
> much help unless it could calculate the required deviation from my current
> position around the mountain then home.

That would be ideal, and I've suggested it to SeeYou, but it's not been
implemented. Maybe the next release. In the meantime, I've found the
warning is more useful than no warning.

> At least for me I would not want to
> leave my margins flying in the mountains so thin that I could just clear a
> pass.

SeeYou uses a "clearance" altitude above the ridge equal to the
"arrival" height chosen for getting to a landing place. I usually use
1000 feet. So, when the red square first appears, it means my projected
glide slope is 999 feet above the terrain.

> Finally all of the instrument manufacturers that feature terrain maps state
> emphatically that they should NOT be used as terrain avoidance instruments.
> My guess is that is due to the inaccuracies of the terrain altitude data.
> I'm not willing to bet my life on that.

Did anything I said sound like I was flying with my eyes closed? The
pilot must use his judgement about reaching a landing place, whether
there is a mountain between it or not. I'm sure you don't head for a
landing place over a national forest at a zero McCready setting, just
because the Ilec says you are 50 feet above glide slope. Come on, give
us PDA users some credit.

--
Eric Greenwell - Washington State, USA
Change "netto" to "net" to email me directly

"Transponders in Sailplanes" on the Soaring Safety Foundation website
www.soaringsafety.org/prevention/articles.html

"A Guide to Self-launching Sailplane Operation" at www.motorglider.org

[Michael Huber]

"Eric Greenwell" wrote:

>> Also I would not find the instrument much help unless it could calculate
>> the required deviation from my current position around the mountain then
>> home.
>
> That would be ideal, and I've suggested it to SeeYou, but it's not been
> implemented. Maybe the next release. In the meantime, I've found the
> warning is more useful than no warning.

GPS-LOG (Freeware!) is once more ahead of its commercial competitors: It can
display an outline of the reachable area taking terrain into account.

Good work Henryk!
Michael

[Kilo Charlie]

"Eric Greenwell" > wrote in message
news:UAG5h.2306$T_.2002@trndny06...
> Kilo Charlie wrote:
> Did anything I said sound like I was flying with my eyes closed? The pilot
> must use his judgement about reaching a landing place, whether there is a
> mountain between it or not. I'm sure you don't head for a landing place
> over a national forest at a zero McCready setting, just because the Ilec
> says you are 50 feet above glide slope. Come on, give us PDA users some
> credit.
>
> --
> Eric Greenwell - Washington State, USA
> Change "netto" to "net" to email me directly

I'm not knocking the "PDA users" Eric. In fact for the record I have a PDA
running SeeYou mobile too as an entirely separate system (in addition to the
SN-10/VL) attached to another VL. I like some of the features of SeeYou but
have found it to be unreliable re altitudes at times. The best way I've
found to keep it within tolerances is to place it in the GPS mode and
unlinked. Do you have a better way of doing it? I haven't noted that
SeeYou gives me clearance heights over terrain but maybe its because I'm
conservative and haven't had it alarm due to that.

Also for the record one of our local pilots was flying in the hills a couple
of years back and did exactly what I stated.....had a Mc zero setting in for
a landable strip and hit huge sink on the way there causing him to have to
land in a very bad area.....large paloverdes and cactus. He was very lucky
to walk away unhurt. The glider was a mess but repairable.

Here in AZ we have encountered some very heavy sink over extended periods in
the mountains and so my point overall is that I would suggest keeping extra
altitude as a safety margin. There are a lot of people that read this
newsgroup and even though some may be a very experienced mountain pilots
others may not be. Squeaking a glide into a strip around mountains sounds
like a setup for problems when hitting bad sink.

Casey

[Stewart Kissel]

There are a lot of people that read this newsgroup
and even though some may be a very experienced mountain
pilots others may not be. Squeaking a glide into a
strip around mountains sounds like a setup for problems
when hitting bad sink.

>Casey

I like PDA's for freeing up my bandwith for analyzing
conditions...but what Casey writes is soooo true.
Time of day, what the wind is doing over the terrain
ahead, cloud cover...are not going to be analyzed and
displayed. At the same altitutude and wind direction/speed,
the computer does not know/care if a decaying Cu-Nim
is on course, or if the day is dying or for that matter
just starting to boom.

[Eric Greenwell]

Kilo Charlie wrote:
..
>
> Here in AZ we have encountered some very heavy sink over extended periods in
> the mountains and so my point overall is that I would suggest keeping extra
> altitude as a safety margin.

I don't just suggest it, I strongly recommend it. The trick is learning
what amounts should be used, where to use them, and when. Extra is
required when wave is about, also. I don't think anyone suggested all
you needed was a terrain warning to keep you safe in the mountains. It's
just an additional tool to help the pilot with his soaring, and I hope
no one thinks they will learn the nuances of mountain soaring from a
thread on ras.

> There are a lot of people that read this
> newsgroup and even though some may be a very experienced mountain pilots
> others may not be. Squeaking a glide into a strip around mountains sounds
> like a setup for problems when hitting bad sink.

I think squeaking a glide into a strip is a setup for problems, flat
land or mountains.

--
Eric Greenwell - Washington State, USA
Change "netto" to "net" to email me directly

"Transponders in Sailplanes" on the Soaring Safety Foundation website
www.soaringsafety.org/prevention/articles.html

"A Guide to Self-launching Sailplane Operation" at www.motorglider.org

[[email protected]]

> Also for the record one of our local pilots was flying in the hills a couple
> of years back and did exactly what I stated.....had a Mc zero setting in for
> a landable strip and hit huge sink on the way there causing him to have to
> land in a very bad area.....large paloverdes and cactus. He was very lucky
> to walk away unhurt. The glider was a mess but repairable.


The same would have happened if he had used the SN10 landable places at
MC 0.

People do not set your glide computer to MC0 as you are not flying the
polar you are flying the conditions.

Al

[Cliff Hilty]

That is a problem with most computers. I want to fly
the 0 Mcready (especially downwind) when trying to
strech to a landable spot, but want to arrive there
higher than 150 meters that the SN10 gives you. The
only way to change that is to abandon the task and
'goto' the alternate on the alternate page and then
change the arrival altitude on the stats page. Too
much to do when in a high stress mode. I would like
to be able to set a ' user set default' for arrival
altitude to alternates that would show the glide to
any selected alternate plus what I have set as a 'user
default'. That way I do not have to abandon the task
and can see the arrival altitude just by going to the
alternates page. Simply less math in my head. While
were at it put the alternates page at the end of the
menu so I can just spin the knob and be there, and
not have to come back 3 small clicks that mowt of the
time takes a few times to get to. Are you reading this
DRN:) Other than that the SN10 is superb! Keep up the
good work. Oh yea PS, put in a USB port and a auto
download to a thumb drive that I can pull and walk
away after flight!))

At 07:01 13 November 2006, wrote:
>
>> Also for the record one of our local pilots was flying
>>in the hills a couple
>> of years back and did exactly what I stated.....had
>>a Mc zero setting in for
>> a landable strip and hit huge sink on the way there
>>causing him to have to
>> land in a very bad area.....large paloverdes and cactus.
>> He was very lucky
>> to walk away unhurt. The glider was a mess but repairable.
>
>
>The same would have happened if he had used the SN10
>landable places at
>MC 0.
>
>People do not set your glide computer to MC0 as you
>are not flying the
>polar you are flying the conditions.
>
>Al
>
>

[[email protected]]

Winpilot Pro basically gives you what you are asking for here.
It will also adjust glide for wind without having to mess with your MC
setting.

As a rule I typically fly with MC set to 3.
It gives about the right glides flying out of Minden

Al



Cliff Hilty wrote:
> That is a problem with most computers. I want to fly
> the 0 Mcready (especially downwind) when trying to
> strech to a landable spot, but want to arrive there
> higher than 150 meters that the SN10 gives you. The
> only way to change that is to abandon the task and
> 'goto' the alternate on the alternate page and then
> change the arrival altitude on the stats page. Too
> much to do when in a high stress mode. I would like
> to be able to set a ' user set default' for arrival
> altitude to alternates that would show the glide to
> any selected alternate plus what I have set as a 'user
> default'. That way I do not have to abandon the task
> and can see the arrival altitude just by going to the
> alternates page. Simply less math in my head. While
> were at it put the alternates page at the end of the
> menu so I can just spin the knob and be there, and
> not have to come back 3 small clicks that mowt of the
> time takes a few times to get to. Are you reading this
> DRN:) Other than that the SN10 is superb! Keep up the
> good work. Oh yea PS, put in a USB port and a auto
> download to a thumb drive that I can pull and walk
> away after flight!))
>
> At 07:01 13 November 2006, wrote:
> >
> >> Also for the record one of our local pilots was flying
> >>in the hills a couple
> >> of years back and did exactly what I stated.....had
> >>a Mc zero setting in for
> >> a landable strip and hit huge sink on the way there
> >>causing him to have to
> >> land in a very bad area.....large paloverdes and cactus.
> >> He was very lucky
> >> to walk away unhurt. The glider was a mess but repairable.
> >
> >
> >The same would have happened if he had used the SN10
> >landable places at
> >MC 0.
> >
> >People do not set your glide computer to MC0 as you
> >are not flying the
> >polar you are flying the conditions.
> >
> >Al
> >
> >

[BB]

> That is a problem with most computers. I want to fly
> the 0 Mcready (especially downwind) when trying to
> strech to a landable spot,

This comment reflects a big misunderstanding of glide computers and how
to use them.

First of all, the SN10 and other computers all include wind in the
calculation of gliding distances. In fact, there is a danger of using
the high altitude winds to think you can stretch much further than you
will be able to when you get lower and the tailwind component is less.

More importantly, calculating glides to landable spots at Mc 0 is
guaranteed to fail. The only time you will glide all the way to the
landable spot is if you miss all the thermals along the way, meaning
you glide there in sink. Catch 22.

The calculator is set up for final glides, over landable terrain. It
assumes lift = sink, which is a reasonable assumption for flying as
fast as possible on average, while taking a risk of landing short if
you hit sink all the way.

For safety, you want to assume the worst possible sink all the way to
landing. Since compters do not now let you set up "give me a glide at
Mc 0 but 5 knot sink" you have to do this by hand. Usually, setting the
glide at Mc 3-4 plus a reserve is a good approximation, but that
depends on weather, how bad terrain really is below you, and so forth.

The only hitch on many computers is you would like to input a higher
MacCready setting for glides to safe fields than you want to fly at.
When in danger, you might want to fly at Mc 0-1 (60 knots) but leave
Mc3-4 glides to your landing areas. Some computers let you do this. For
example, GNII lets you turn off Mc exchange, so you can set GNII to
Mc3-4 for landing calcuations but manually set the speed to fly vario
at Mc0-1. Otherwise, turn up the MacCready for glides and ignore the
instrument screaming at you to fly 90 knots.

John Cochrane

[Eric Greenwell]

BB wrote:

>
> The only hitch on many computers is you would like to input a higher
> MacCready setting for glides to safe fields than you want to fly at.
> When in danger, you might want to fly at Mc 0-1 (60 knots) but leave
> Mc3-4 glides to your landing areas. Some computers let you do this. For
> example, GNII lets you turn off Mc exchange, so you can set GNII to
> Mc3-4 for landing calcuations but manually set the speed to fly vario
> at Mc0-1.

I'm so glad to read it's not just me that wants to do this. I did as
John suggests when I used GNII, and I now do the same with SeeYou
Mobile, which also allows blocking the Mc exchange. I used to do it even
before flight computers, where I set the Mc ring on the vario lower than
the Mc setting on the plastic "prayer wheel".

For the ASW 20 and now the ASH 26 E, I find myself typically using a 2
knot Mc setting on the vario, a 4 knot setting on the flight computer,
and 5 knot thermals.

--
Eric Greenwell - Washington State, USA
Change "netto" to "net" to email me directly

"Transponders in Sailplanes" on the Soaring Safety Foundation website
www.soaringsafety.org/prevention/articles.html

"A Guide to Self-launching Sailplane Operation" at www.motorglider.org

[kirk.stant]

Or try a different tack: I've been using L/D to the landing field
instead of an MC-adjusted altitude. This does require one to know what
his glider will do under various conditions (no/tail/headwind, bugs,
etc) but allows a quick and easy analysis of the fields in (or not in!)
range.

I use to do this using my Garmin Pilot 3 (the vnav L/D feature), and
now use SeeYou Mobile for the same thing. By setting the MC high
enough, the L/D boxes change from yellow to green at about 30/1, which
is when I start to consider an alternate safe in my LS6. Makes it easy
to glance at the PDA to see where the closest possible alternate is (or
isn't).

I use my SN10 for "real" final glides, set for wind and bugs and etc.,
and if I have to divert will use it to the divert,if possible,
especially if wind is a factor. But have made final glides using L/D
only, and it works fine - especially for a short range low altitude
last minute landout - you know, the kind when you realize 10 miles out
that you aren't going to make it home and have to take a snap vector to
some field you have never been to before...

Like Tom, I get all my tactical data from the SN10; my PDA is limited
to the moving map with alternates and task line - essentially a
simplified glass sectional. And it is my backup (independent
GPS/logger) in case all the blue smoke leaks out of my SN10.

Re the original subject, I have no experience with the 302 (other than
being beaten by guys using them, and vice versa), but I do think the
SN10 is an excellent bit of kit!

Kirk
66

[HL Falbaum]

I use a 302/Winpilot Pro/3955--which does everything I want on one page. I
can "disconnect" the MC setting and thus set MC in the 302 speed command for
one setting, and the MC in Winpilot final glide gets another. I have flown
with SN10 and LX7000---I find they are all nice. I have been told by experts
that the SN10 has the best variiometer, but without side-by-side comparison
in the same glider, it's hard to tell. Winpilot Pro has a "thermal history"
graphic presenting similar info to the SN10. The only drawback is that the
Winpilot has so many features, it takes a while to sort out the useful from
the merely interesting. The program will take at least a season to learn to
use effectively. The variometry of the 302 is at least good-to-excellent.
The 302 has a backup battery--does the SN10? I have had the 302 several
years--it's been back to the shop twice--once to replace the polarization
screen so I could read it with polarized sunglasses, and once to convert it
to a motorglider version.

--
Hartley Falbaum


"kirk.stant" > wrote in message
ups.com...
> Or try a different tack: I've been using L/D to the landing field
> instead of an MC-adjusted altitude. This does require one to know what
> his glider will do under various conditions (no/tail/headwind, bugs,
> etc) but allows a quick and easy analysis of the fields in (or not in!)
> range.
>
> I use to do this using my Garmin Pilot 3 (the vnav L/D feature), and
> now use SeeYou Mobile for the same thing. By setting the MC high
> enough, the L/D boxes change from yellow to green at about 30/1, which
> is when I start to consider an alternate safe in my LS6. Makes it easy
> to glance at the PDA to see where the closest possible alternate is (or
> isn't).
>
> I use my SN10 for "real" final glides, set for wind and bugs and etc.,
> and if I have to divert will use it to the divert,if possible,
> especially if wind is a factor. But have made final glides using L/D
> only, and it works fine - especially for a short range low altitude
> last minute landout - you know, the kind when you realize 10 miles out
> that you aren't going to make it home and have to take a snap vector to
> some field you have never been to before...
>
> Like Tom, I get all my tactical data from the SN10; my PDA is limited
> to the moving map with alternates and task line - essentially a
> simplified glass sectional. And it is my backup (independent
> GPS/logger) in case all the blue smoke leaks out of my SN10.
>
> Re the original subject, I have no experience with the 302 (other than
> being beaten by guys using them, and vice versa), but I do think the
> SN10 is an excellent bit of kit!
>
> Kirk
> 66
>