New Transponder for us

In article
,
Darryl Ramm wrote:

A good rough number for steady state consumption for an ACK-30 encoder
(what most of us with Mode C transponders in gliders use today) is a
bit over 60mA @ 12VDC without the heater on. Heater full on they can
draw 400mA @ 12VDC (luckily the heater should not be on often in
usual use - but if you are flying in wave especially make sure the
encoder box is insulated and protected from drafts).

Pardon me for hijacking the thread, but this suddenly made me realize
that I've been wondering about these encoders for a while.

This is probably obvious to those in the know, but alas, it's not coming
to me. Why is it that a transponder encoder requires a heater, when a
mechanical altimeter functions just fine on its own?

--
Mike Ash
Radio Free Earth
Broadcasting from our climate-controlled studios deep inside the Moon

On Dec 9, 8:58*am, Richard wrote:
Trig TT21 Class 2 Mode C Transponder with Built-in Altitude Encoder
$2095

If you compare to the 35,000' * * * $700 to $800 Less

Right, but you can buy the TT21 for a lot less than that if you shop
around. Trig has a minimum advertised retail price policy but some
vendors are selling much lower. It's the old "put one in the order
basket to see the real price" trick.

Check Aircraft Spruce as an example.

Andy

On Dec 9, 8:22*am, Andy wrote:
On Dec 9, 8:58*am, Richard wrote:

Trig TT21 Class 2 Mode C Transponder with Built-in Altitude Encoder
$2095

If you compare to the 35,000' * * * $700 to $800 Less

Right, but you can buy the TT21 for a lot less than that if you shop
around. *Trig has a minimum advertised retail price policy but some
vendors are selling much lower. *It's the old "put one in the order
basket to see the real price" trick.

Check Aircraft Spruce as an example.

Andy


Richard

You seem to be referring to this page http://www.cumulus-soaring.com/trig.htm
I expect Paul will have the "Mode C" typo fixed asap, but the same
page has lots of information on the Trig TT21/22 making clear they are
Mode S transponder.

---

There are at least three USA glider dealers actively selling the Trig
TT21.

Cumulus Soaring - http://www.cumulus-soaring.com/trig.htm
Williams Soaring - http://www.williamssoaring.com/catalog/index.html
(a dealer but no Trig info on their web store yet)
Wings and Wheels -
http://www.wingsandwheels.com/Transp...20Microair.htm

And Tim there is advertising this new Sandia transponder as well. Jeez
Tim! Maybe Tim or Richard can clarify the actual 12 VDC power
consumption of the Sandia transponder.

I understand the USA Trig distributor wanted higher upfront commitment
from the channel than other distributors and that may be a reason why
fewer dealers are carrying them than other brands. I don't know why
Craggy Aero does not sell the Trig transponders. It would seems a very
natural fit for the PowerFLARM that Craggy Aero has been doing a great
job promoting.

As for the relative cost. Most glider pilots do just fine installing a
lower cost and lower power consumption 125W transponder (whether a new
Trig TT21 or the Becker ATC-4401-175 many of us use). So for new
transponders for gliders in the USA any price comparison really should
be against the street price of a TT21. It really is irrelevant that
the Sandia is a 200W transponder, that does not justify a price
comparison to a Trig TT22 200W transponder. And as others have pointed
out we need to be a little careful comparing advertised and actual
street prices.

It is great to see pilots using a transponder (any transponder) where
we have high density airliner and fast jet traffic etc. and a Mode S
or Mode C transponder works well there today (but its the long term
ADS-B future where a Mode S shines). But I'd hate to see glider pilots
not aware of the issues and thinking that buying a cheaper Mode C
transponder today is a better decision than a slightly more expensive
Mode S transponder, especially when all the other important specs are
better with the Mode S. And I'd definitively not like to see us as a
community back in a situation where pilots are discussing debilitating
transponder power usage and more rounds of misinformation on power
consumption, and lack of use of transponders, because of this.

So Richard or Tim or anybody else do you have actual 12 VDC power
consumption specs on the Sandia transponder?

Darryl

The only data available on the Sandia transponder is from their brouchure
(also on my website page in PDF)
but essentially says:
The STX 165 Sports a professional 1/2 3ATI Bezel that compliments any
aircraft panel. Its bright OLED
display is readable in virtually all lighting conditions and automatically
dims for night time operations. Check out just a few of the STX 165
features.

Built-in Encoder Simplifies installations and lowers cost.
Three Timer Functions Elapsed Flight Time, Up Timer, Down Timer
Pressure Altitude Display See what altitude your transponder is reporting
to Center
Optional OAT Probe Input Displays Outside Air Temp.,Density Altitude,
Icing Alert
Small and Light Weight 7.4" behind the panel depth, 1.3 lbs.
Low Current Requirements Ideal for LSA - Glider - UAV Operations

I have had these on order for several months so will get the very first ones
once they are releases..looks very promissing though for glider use noting
that they do say Low Current Requirements Ideal for LSA - Glider - UAV
Operations
please stand by!

I think also the next this to keep in mind and likely coming available
sometime in the not too distant future is UTA systems that I think you'll
find capabilities for this from Sandia to compliment their transponder
developement... http://www.itt.com/adsb/adsb-explained.html

Merry Chritmas!
Tim

Wings and Wheels -
http://www.wingsandwheels.com/Transp...20Microair.htm


And Tim there is advertising this new Sandia transponder as well. Jeez
Tim! Maybe Tim or Richard can clarify the actual 12 VDC power
consumption of the Sandia transponder.

I understand the USA Trig distributor wanted higher upfront commitment
from the channel than other distributors and that may be a reason why
fewer dealers are carrying them than other brands. I don't know why
Craggy Aero does not sell the Trig transponders. It would seems a very
natural fit for the PowerFLARM that Craggy Aero has been doing a great
job promoting.

As for the relative cost. Most glider pilots do just fine installing a
lower cost and lower power consumption 125W transponder (whether a new
Trig TT21 or the Becker ATC-4401-175 many of us use). So for new
transponders for gliders in the USA any price comparison really should
be against the street price of a TT21. It really is irrelevant that
the Sandia is a 200W transponder, that does not justify a price
comparison to a Trig TT22 200W transponder. And as others have pointed
out we need to be a little careful comparing advertised and actual
street prices.

It is great to see pilots using a transponder (any transponder) where
we have high density airliner and fast jet traffic etc. and a Mode S
or Mode C transponder works well there today (but its the long term
ADS-B future where a Mode S shines). But I'd hate to see glider pilots
not aware of the issues and thinking that buying a cheaper Mode C
transponder today is a better decision than a slightly more expensive
Mode S transponder, especially when all the other important specs are
better with the Mode S. And I'd definitively not like to see us as a
community back in a situation where pilots are discussing debilitating
transponder power usage and more rounds of misinformation on power
consumption, and lack of use of transponders, because of this.

So Richard or Tim or anybody else do you have actual 12 VDC power
consumption specs on the Sandia transponder?

Darryl

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On Dec 9, 12:30*pm, "Tim Mara" wrote:
The only data available on the Sandia transponder is from their brouchure
(also on my website page in PDF)
but essentially says:
The STX 165 Sports a professional 1/2 3ATI Bezel that compliments any
aircraft panel. *Its bright OLED
display is readable in virtually all lighting conditions and automatically
dims for night time operations. *Check out just a few of the STX 165
features.

Built-in Encoder *Simplifies installations and lowers cost.
Three Timer Functions *Elapsed Flight Time, Up Timer, Down Timer
Pressure Altitude Display *See what altitude your transponder is reporting
to Center
Optional OAT Probe Input * Displays Outside Air Temp.,Density Altitude,
Icing Alert
Small and Light Weight *7.4" behind the panel depth, 1.3 lbs.
Low Current Requirements *Ideal for LSA - Glider - UAV Operations

I have had these on order for several months so will get the very first ones
once they are releases..looks very promissing though for glider use noting
that they do say *Low Current Requirements *Ideal for LSA - Glider - UAV
Operations
please stand by!

I think also the next this to keep in mind and likely coming available
sometime in the not too distant future is UTA systems that I think you'll
find capabilities for this from Sandia to compliment their transponder
developement...http://www.itt.com/adsb/adsb-explained.html

Merry Chritmas!
Tim

Tim, that is not all the data in the brochure. You left off the most
relevant actual numerical power consumption data, but included the
marketing fluff claims. The brochure states 500mA power consumption at
28VDC. Assuming perfect power supply behavior that translates to 1.1 A
current draw at 12VDC. That just seems an unusably high current draw
for use in gliders - can you check with Sandia on the correct 12 VDC
(or 14VDC) power consumption?

Sandia Aerospace has been active in UAT development and may well
beleive UATs are important for the USA market, but it is very
surprising they extrpolate this to justufy the development of a new
Mode C transponder. Sofar the lowest cost (non TSO) UAT transceivers
avalable would more than double the price again of this system to do
ADS-B data-out, and add even more power consumption (getting close to
2A?!) and that still gets you UAT only that will have significant
compatibility issues with the 1090ES link supported by PowerFLARM.

Besides all the other problems I'm just not sure I would want to buy a
product from a small company who thinks developing a Mode C
transponder in 2010 is a good idea. It gives me no confidence they
will be around to provide support in the future.

Darryl

Actually the data on their brochure is actually pessimistic. In speaking
with the company directly this is all based on test data and in worst case
scenarios during warm up, transmitting on the 7777 frequency and at full
power...what they confirm as an estimate of current consumption at 12 VDC is
likely much closer to 500 mA .very doable in almost any glider application
and will operate down to 11 Volts.
There are several relevant arguments for both Mode C and also for UAT
including lower power requirements than Mode S (at similar power output) and
the possibility of simple and lower cost displays for all traffic, not
simply aircraft equipped with FLARM in that UAT will show all transponder
equipped aircraft. The cost appears higher but at an estimated price
possibility of about $3500 +/- that would not only include the UTA but the
transponder as well..We easily see prices in the same range for transponder
and FLARM / PowerFLARM equipment and the UAT can also provide a TCAS type
warning and display in a glider size package.
tim


"Darryl Ramm" wrote in message
...
On Dec 9, 12:30 pm, "Tim Mara" wrote:
The only data available on the Sandia transponder is from their brouchure
(also on my website page in PDF)
but essentially says:
The STX 165 Sports a professional 1/2 3ATI Bezel that compliments any
aircraft panel. Its bright OLED
display is readable in virtually all lighting conditions and automatically
dims for night time operations. Check out just a few of the STX 165
features.

Built-in Encoder Simplifies installations and lowers cost.
Three Timer Functions Elapsed Flight Time, Up Timer, Down Timer
Pressure Altitude Display See what altitude your transponder is reporting
to Center
Optional OAT Probe Input Displays Outside Air Temp.,Density Altitude,
Icing Alert
Small and Light Weight 7.4" behind the panel depth, 1.3 lbs.
Low Current Requirements Ideal for LSA - Glider - UAV Operations

I have had these on order for several months so will get the very first
ones
once they are releases..looks very promissing though for glider use noting
that they do say Low Current Requirements Ideal for LSA - Glider - UAV
Operations
please stand by!

I think also the next this to keep in mind and likely coming available
sometime in the not too distant future is UTA systems that I think you'll
find capabilities for this from Sandia to compliment their transponder
developement...http://www.itt.com/adsb/adsb-explained.html

Merry Chritmas!
Tim

Tim, that is not all the data in the brochure. You left off the most
relevant actual numerical power consumption data, but included the
marketing fluff claims. The brochure states 500mA power consumption at
28VDC. Assuming perfect power supply behavior that translates to 1.1 A
current draw at 12VDC. That just seems an unusably high current draw
for use in gliders - can you check with Sandia on the correct 12 VDC
(or 14VDC) power consumption?

Sandia Aerospace has been active in UAT development and may well
beleive UATs are important for the USA market, but it is very
surprising they extrpolate this to justufy the development of a new
Mode C transponder. Sofar the lowest cost (non TSO) UAT transceivers
avalable would more than double the price again of this system to do
ADS-B data-out, and add even more power consumption (getting close to
2A?!) and that still gets you UAT only that will have significant
compatibility issues with the 1090ES link supported by PowerFLARM.

Besides all the other problems I'm just not sure I would want to buy a
product from a small company who thinks developing a Mode C
transponder in 2010 is a good idea. It gives me no confidence they
will be around to provide support in the future.

Darryl



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database 5689 (20101209) __________

The message was checked by ESET NOD32 Antivirus.

http://www.eset.com





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On Dec 9, 2:10*pm, "Tim Mara" wrote:
Actually the data on their brochure is actually pessimistic. In speaking
with the company directly this is all based on test data and in worst case
scenarios during warm up, transmitting on the 7777 frequency and at full
power...what they confirm as an estimate of current consumption at 12 VDC is
likely much closer to 500 mA .very doable in almost any glider application
and will operate down to 11 Volts.
There are several relevant arguments for both Mode C and also for UAT
including lower power requirements than Mode S (at similar power output) and
the possibility of simple and lower cost displays for all traffic, not
simply aircraft equipped with FLARM in that UAT will show all transponder
equipped aircraft. The cost appears higher but at an estimated price
possibility of about $3500 +/- that would not only include the UTA but the
transponder as well..We easily see prices in the same range for transponder
and FLARM / PowerFLARM equipment and the UAT can also provide a TCAS type
warning and display in a glider size package.
tim

As has been covered in this thread. Yes a Mode S individual
interrogation rely may use more power than a Mode C reply (one that is
mostly no/null pulses) but a mode S transponder may well use less
power in practical situations that a Mode C due to the reduced number
of interrogations that the Mode S transponder will reply to. We see
that in practice, the Trig TT21 is flying in gliders with power
consumption 300mA including encoder. Spectaculary low power
consumption - proving you can do this with a Mode S transponder.

A UAT based traffic system can provide a TCAS I like warning - every
traffic systems with direction information can provide a TCAS I like
traffic alert (TA). None, including Flarm or anything Sandia develop
based on a UAT can provide a TCAS II like RA. There is nothing unique
in that claim.

The "see all transponders" you mention is TIS-B. PowerFLARM does that
just just as well (and as bad) as a UAT receiver will well when the
PowewrFLARM equipped aircraft with 1090ES data-out. It has nothing to
do with using Mode C per-se.

To see that you need ADS-B data out either UAT or 1090ES and a
receiver (on the same link layer is preferred).

And you need to be within coverage of a GBT and the TIS-B service
needs to be deployed where you are flying (and the deployments differ
for en-route or terminal volumes). And even then the resolution of TIS-
B won't allow things like close flying of gliders etc.

The practical danger is that in many situations a PowerFLARM equipped
glider would see a glider equipped with Mode C becuase of the PCAS in
the PowerFLARM but this Sandia Mode C + UAT won't see a PowerFLARM
equipped glider at all because it won't be within GBT coverage, even
if the glider is transponder equipped.

So you really want to push Mode C + UAT as an alternative to
PowerFLARM? I hope people really get that the several hundred and
growing early orders for PowerFLARM in the USA means that thinking
about UAT technology and gliders in the USA is not a good idea. That
was last decade's dream that did not happen. It is a real concern that
we have critical traffic areas (like the white mountains and ridges
back east) where we need to think about technology to help avoid
glider on glider collisions and where mixed PowerFLARM and UAT
technology should not be expected to work. I hope potential purchasers
and dealers really understand the issues here. And where the primary
concern is glider on glider traffic all owners need to purchase is a
PowerFLARM (and they'll still get PCAS alerts for GA traffic as long
as that transponder equipped traffic is being interrogated).

Any though process for doing ADS-B via Mode C plus UAT ought to have
some *huge* benefit vs. PowerFLARM + 1090ES data-out. About the same
price and about the same power consumption (or more) but having
serious compatibility issues with a large number of PowerFLARM
equipped gliders seems a pretty dangerous direction to advocate.

Darryl

On 12/9/2010 6:16 PM, Darryl Ramm wrote:
On Dec 9, 2:10 pm, "Tim wrote:
Actually the data on their brochure is actually pessimistic. In speaking
with the company directly this is all based on test data and in worst case
scenarios during warm up, transmitting on the 7777 frequency and at full
power...what they confirm as an estimate of current consumption at 12 VDC is
likely much closer to500 mA .very doable in almost any glider application
and will operate down to11 Volts.
There are several relevant arguments for both Mode C and also for UAT
including lower power requirements than Mode S (at similar power output) and
the possibility of simple and lower cost displays for all traffic, not
simply aircraft equipped with FLARM in that UAT will show all transponder
equipped aircraft. The cost appears higher but at an estimated price
possibility of about $3500 +/- that would not only include the UTA but the
transponder as well..We easily see prices in the same range for transponder
and FLARM / PowerFLARM equipment and the UAT can also provide a TCAS type
warning and display in a glider size package.
tim

As has been covered in this thread. Yes a Mode S individual
interrogation rely may use more power than a Mode C reply (one that is
mostly no/null pulses) but a mode S transponder may well use less
power in practical situations that a Mode C due to the reduced number
of interrogations that the Mode S transponder will reply to. We see
that in practice, the Trig TT21 is flying in gliders with power
consumption 300mA including encoder. Spectaculary low power
consumption - proving you can do this with a Mode S transponder.

A UAT based traffic system can provide a TCAS I like warning - every
traffic systems with direction information can provide a TCAS I like
traffic alert (TA). None, including Flarm or anything Sandia develop
based on a UAT can provide a TCAS II like RA. There is nothing unique
in that claim.

The "see all transponders" you mention is TIS-B. PowerFLARM does that
just just as well (and as bad) as a UAT receiver will well when the
PowewrFLARM equipped aircraft with 1090ES data-out. It has nothing to
do with using Mode C per-se.

To see that you need ADS-B data out either UAT or 1090ES and a
receiver (on the same link layer is preferred).

And you need to be within coverage of a GBT and the TIS-B service
needs to be deployed where you are flying (and the deployments differ
for en-route or terminal volumes). And even then the resolution of TIS-
B won't allow things like close flying of gliders etc.

The practical danger is that in many situations a PowerFLARM equipped
glider would see a glider equipped with Mode C becuase of the PCAS in
the PowerFLARM but this Sandia Mode C + UAT won't see a PowerFLARM
equipped glider at all because it won't be within GBT coverage, even
if the glider is transponder equipped.

So you really want to push Mode C + UAT as an alternative to
PowerFLARM? I hope people really get that the several hundred and
growing early orders for PowerFLARM in the USA means that thinking
about UAT technology and gliders in the USA is not a good idea. That
was last decade's dream that did not happen. It is a real concern that
we have critical traffic areas (like the white mountains and ridges
back east) where we need to think about technology to help avoid
glider on glider collisions and where mixed PowerFLARM and UAT
technology should not be expected to work. I hope potential purchasers
and dealers really understand the issues here. And where the primary
concern is glider on glider traffic all owners need to purchase is a
PowerFLARM (and they'll still get PCAS alerts for GA traffic as long
as that transponder equipped traffic is being interrogated).

Any though process for doing ADS-B via Mode C plus UAT ought to have
some *huge* benefit vs. PowerFLARM + 1090ES data-out. About the same
price and about the same power consumption (or more) but having
serious compatibility issues with a large number of PowerFLARM
equipped gliders seems a pretty dangerous direction to advocate.

Darryl

I can't let this post go unanswered. Saying that PowerFlarm is the
answer for the glider community and UAT was last decade's dream is
pushing the limits. PowerFlarm doesn't even exist yet. UAT is the
FAA's recommended solution for GA, so I wouldn't be writing that off so
easily.

I'm not going to predict how this all falls out. There will undoubtedly
be lots of ADS-B solutions coming out in the next few years, both 1090ES
and UAT based. I'm not going to predict which way the market is going
to go, which will likely be heavily influenced by pricing.

If GARMIN decides to make a major push in this space for the single
engine VFR GA market, things could change in a very big way. Given the
size of this market, it's hard to imagine that GARMIN isn't going to
pursue this aggressively. If their mass market product is UAT based,
and you have 50-80% of the GA market equip, having gliders standardizing
on 1090ES is going to be a pretty bad move if you are flying low or in
remote areas, where you don't have ground station coverage to translate
between systems.

If you have the money and want to buy something right now, a 1090ES
capable Mode S transponder sounds like a reasonable investment.
PowerFlarm might also fall into that category IF you are an active
contest pilot, or are flying in an area where there are a critical mass
of glider pilots making the same investment in the near term.
Otherwise, at this point anything else is betting on untested marketing
spec sheets and speculating on a somewhat unpredictable market.

--
Mike Schumann

On Dec 9, 7:07*pm, Mike Schumann
wrote:
On 12/9/2010 6:16 PM, Darryl Ramm wrote:



On Dec 9, 2:10 pm, "Tim *wrote:
Actually the data on their brochure is actually pessimistic. In speaking
with the company directly this is all based on test data and in worst case
scenarios during warm up, transmitting on the 7777 frequency and at full
power...what they confirm as an estimate of current consumption at 12 VDC is
likely much closer to500 mA .very doable in almost any glider application
and will operate down to11 Volts.
There are several relevant arguments for both Mode C and also for UAT
including lower power requirements than Mode S (at similar power output) and
the possibility of simple and lower cost displays for all traffic, not
simply aircraft equipped with FLARM in that UAT will show all transponder
equipped aircraft. The cost appears higher but at an estimated price
possibility of about $3500 +/- that would not only include the UTA but the
transponder as well..We easily see prices in the same range for transponder
and FLARM / PowerFLARM equipment and the UAT can also provide a TCAS type
warning and display in a glider size package.
tim

As has been covered in this thread. Yes a Mode S individual
interrogation rely may use more power than a Mode C reply (one that is
mostly no/null pulses) but a mode S transponder may well use less
power in practical situations that a Mode C due to the reduced number
of interrogations that the Mode S transponder will reply to. We see
that in practice, the Trig TT21 is flying in gliders with power
consumption *300mA including encoder. Spectaculary low power
consumption - proving you can do this with a Mode S transponder.

A UAT based traffic system can provide a TCAS I like warning - every
traffic systems with direction information can provide a TCAS I like
traffic alert (TA). None, including Flarm or anything Sandia develop
based on a UAT can provide a TCAS II like RA. There is nothing unique
in that claim.

The "see all transponders" you mention is TIS-B. PowerFLARM does that
just just as well (and as bad) as a UAT receiver will well when the
PowewrFLARM equipped aircraft with 1090ES data-out. It has nothing to
do with using Mode C per-se.

To see that you need ADS-B data out either UAT or 1090ES and a
receiver (on the same link layer is preferred).

And you need to be within coverage of a GBT and the TIS-B service
needs to be deployed where you are flying (and the deployments differ
for en-route or terminal volumes). And even then the resolution of TIS-
B won't allow things like close flying of gliders etc.

The practical danger is that in many situations a PowerFLARM equipped
glider would see a glider equipped with Mode C becuase of the PCAS in
the PowerFLARM but this Sandia Mode C + UAT won't see a PowerFLARM
equipped glider at all because it won't be within GBT coverage, even
if the glider is transponder equipped.

So you really want to push Mode C + UAT as an alternative to
PowerFLARM? I hope people really get that the several hundred and
growing early orders for PowerFLARM in the USA means that thinking
about UAT technology and gliders in the USA is not a good idea. That
was last decade's dream that did not happen. It is a real concern that
we have critical traffic areas (like the white mountains and ridges
back east) where we need to think about technology to help avoid
glider on glider collisions and where mixed PowerFLARM and UAT
technology should not be expected to work. I hope potential purchasers
and dealers really understand the issues here. And where the primary
concern is glider on glider traffic all owners need to purchase is a
PowerFLARM (and they'll still get PCAS alerts for GA traffic as long
as that transponder equipped traffic is being interrogated).

Any though process for doing ADS-B via Mode C plus UAT ought to have
some *huge* benefit vs. PowerFLARM + 1090ES data-out. About the same
price and about the same power consumption (or more) but having
serious compatibility issues with a large number of PowerFLARM
equipped gliders seems a pretty dangerous direction to advocate.

Darryl

I can't let this post go unanswered. *Saying that PowerFlarm is the
answer for the glider community and UAT was last decade's dream is
pushing the limits. *PowerFlarm doesn't even exist yet. *UAT is the
FAA's recommended solution for GA, so I wouldn't be writing that off so
easily.

I'm not going to predict how this all falls out. *There will undoubtedly
be lots of ADS-B solutions coming out in the next few years, both 1090ES
and UAT based. *I'm not going to predict which way the market is going
to go, which will likely be heavily influenced by pricing.

If GARMIN decides to make a major push in this space for the single
engine VFR GA market, things could change in a very big way. *Given the
size of this market, it's hard to imagine that GARMIN isn't going to
pursue this aggressively. *If their mass market product is UAT based,
and you have 50-80% of the GA market equip, having gliders standardizing
on 1090ES is going to be a pretty bad move if you are flying low or in
remote areas, where you don't have ground station coverage to translate
between systems.

If you have the money and want to buy something right now, a 1090ES
capable Mode S transponder sounds like a reasonable investment.
PowerFlarm might also fall into that category IF you are an active
contest pilot, or are flying in an area where there are a critical mass
of glider pilots making the same investment in the near term.
Otherwise, at this point anything else is betting on untested marketing
spec sheets and speculating on a somewhat unpredictable market.

--
Mike Schumann

PowerFLARM is coming - months away and hundreds of orders. The facts
are there are hundreds of glider pilots in the USA committing to buy
PowerFLARM and the number is growing. That is a huge factor in the
future ADS-B landscape for gliders in the USA that cannot be ignored.
Meanwhile there is still no UAT product suitable for use in gliders,
or any on the visible horizon. It exactly was last decades dream (for
the magical thing that was goign to solve all our glider collision
avoidance needs--that dream is dead). What UATs do in the GA market is
to be seen. As I have said multiple times, they may find a place
amongst GA aircraft with existing Mode C transponders, but overall I
am skeptical for market and packaging reasons they will ever become
more significant than 1090ES data-out in the GA market.

It is hard to be sure of Garmin's strategy here, but here is some
speculation since you raised it.... They have the GDL-90 UAT that was
relatively old technology from Apollo for the Capstone trials in
Alaska and they kept it around but it is pretty long in the tooth and
and they've not announced any updates/future plans yet AFAIK. Their
more recent focus was on adding 1090ES data-out options and upgrades
to their GTX330 and GTX33 transponders and adding 1090ES data-in as
standard on their GTS series traffic systems. L3 and Avidyne the two
other leading GA focused vendors of traffic awareness/alert systems
all have or are adding 1090ES data-in to their traffic systems. Not to
be unexpected for any active traffic system based on transponders--but
that is what the market leaders are doing.

I expect Garmin, L3, and Avidyne to take that 1090ES data-in
capability they have just added to their active TAS/TCAD systems and
and do much lower cost 1090ES data-in only systems around the same
hardware/software. If I was them I'd also do a UAT receive only
capability in that box to get FIS-B and dual-link traffic reception
(for when outside ADS-R coverage) and I would market it as pretty much
addressing most of the dual link ADS-B crap issues. All these vendors
have such good coverage with 1090ES already I'm not sure it justifies
a full parallel UAT product range but Garmin may well do a full
refresh on the GDL-90 who knows. What Garmin does, because they
dominate much of the transponder, display and WAAS GPS market will
have huge impact.

Zaon has been variously rumored to be doing different things,
including a multi-link 1090ES/PCAS/UAT receiver. Who knows what they
are really up to. But I kind of expect them not to do a certified
transmitter, a bit too much for them to bite off at a guess.

Trig has their own 1090ES receiver products coming into the market
that look a great match for 1090ES data-out in their transponders for
the GA market.

Recently Dynon the leading vendor of glass panel hardware for the
experimental market has OEMed the Trig TT series Mode S transponders
as back-ends to their Skyview systems. One could speculate on what
else they might OEM in 1090ES data-in land in future.

I expect Becker to do 1090ES data-in devices in future.

And we have NavWorx, FreeFlight and Sandia Aerospace doing UAT
receiver and transceiver products and SkyRadar doing their interesting
WiFi enabled UAT receiver.

But all of this is pretty academic, for several years, until we get
side service rollout and issues like the STC requirements for
installation of ADS-B data-out are removed. Until then most gliders
owners wanting collision avoidance technology can choose any
combination of Mode C or S transponders, PCAS devices (Zaon MRX) or
(soon) PowerFLARM depending on their need.

But one thing is clear, there is significant orders already in place
for PowerFLARM and that moves the glider community in the USA towards
a 1090ES ADS-B future.

Darryl

Hi,
I do not know if the thread is still open but wanted to jump in and make a statement or three. My name is Barry LeBlanc, Sandia Aerospace Representive. Here is a AC20-165A link. I have cut and posted some of the high lights.
FAA Advisory Circular AC No: 20-165A found on line at:
http://www.faa.gov/documentLibrary/m...%2020-165A.pdf

3-2. ADS-B Equipment.
a. Equipment eligibility. ADS-B equipment must meet the requirements specified in TSO-C166b or TSO-C154c.
b. Installation guidance.
(1) UAT systems with Mode S transponders. Do not install a UAT ADS-B OUT system which has the capability to transmit a random 24-bit address in an aircraft which also has a Mode S transponder unless the random 24-bit feature is disabled. The ATC automation system would interpret the different 24-bit addresses as two separate aircraft, and alert controllers to a conflict that does not actually exist.
(2) Mixed transmit/receive classifications. TSO-C166b and TSO-C154c allow Class A transmit-only and Class A receive-only equipment configurations. There are no restrictions for installing a certain class of receive equipment with a different class of transmit equipment. For example, a Class A3 transmit-only unit can be used in the same aircraft with a Class A1 receive-only unit. It is also acceptable to have a TSO-C166b transmitter and a TSO-C154c receiver and vice versa.
(3) Stand alone 1090ES transmitters. RTCA/DO-260B, paragraph 2.2.2.2 only allows Class A0 and B0 1090ES stand-alone (not integrated with a transponder) transmitters. This AC does not cover installation approval for class A0 or B0 1090ES transmitters because they are not compliant with 14 CFR 91.227.

(4) Multiple ADS-B OUT systems. If the aircraft has the ability to operate a 1090ES and a UAT ADS-B OUT system at the same time, the systems must have a single point of entry for the emergency code, IDENT, and Mode 3/A code. Neither system may use a random address feature. If dual ADS-B OUT systems of the same link are installed (e.g., to increase dispatch reliability), the installation must preclude operation of both systems simultaneously

Note: 1: We recommend that you do not install both 1090ES and UAT ADS-B OUT capability on the same aircraft.


I have more to add. But my email is barry.leblanc at sandia.aero
Look forward to hearing from you why not a MODE C Transponder?