FLARM.....for good, or evil??

Mike, you have just confirmed what I just suspected. Again, ADS-b is
designed for keeping airplanes that want to stay apart, apart. And
yes, I understand exactly what the ground infrastructure is for, and
it's not gliders - It's for IFR air traffic control and GA planes
working their way through bad weather, checking on the latest NOTAMs
at their destination. Sure, "someone" could develop software and
hardware to use ADS-b to do what FLARM has been doing for the past 10
years, BUT THE CHANCE OF THAT HAPPENING IN THE NEAR FUTURE IS A CLOSE
APPROXIMATION OF ZERO!

Can't you understand that this isn't a zero sum game? NOTHING
prevents you from having FLARM now (in Europe) or next year (in the
US, hopefully) and later, if and when ADS-b becomes affordable and
useable in a glider cockpit, installing ADS-b in their glider. And
that even if the FAA gave a free UAT to every aircraft out there,
FLARM would still be useful in the glider community?

The two systems overlap each other, but occupy different requirement
niches.


Kirk
66

On Oct 29, 9:00*am, wrote:
On 10/29/2010 11:16 AM, Mike Schumann wrote:

If the fundamental focus had been on affordability, there is no reason
that we couldn't now have commercial ADS-B equipment at the same price
points as FLARM units.

NavWorx announced on Wednesday Oct. 27 that they are currently shipping
the ADS600B transceivers.
They offer their informal solution to the FAA's STC and/or TSO mandates

can be installed on both experimental and certified aircraft when it meets “portable installation guidelines.”



I think we need to be fairly cautious parsing marketing talk.

On the page at http://www.navworx.com/myths.asp NavWorx is trying to
handle what they probably see as an wide negative view on ADS-B
adoption now from lots of commentators and organizations like AOPA,
authors in Flying Magazine, etc. Probably not what NavWorx intended
but having a read of all the links/comments they give there provides a
pretty good summary of the current negative-side view of ADS-B
adoption.

The reference above was to this statement from NavWorx...

"FAA memo mandates that all ADS-B equipment must be installed via STC
and meet TSO-C166b or TSO-C154c. NavWorx is compliant with TSO-C154c
providing both TIS-B and FIS-B. NavWorx equipment is available today
and can be installed on both experimental and certified aircraft when
it meets “portable installation guidelines.”"

Lets parse the two important bits of that statements carefully

**NavWorx [products] are compliant with TSO-C154c**

That is not saying the products are manufacted under TSO approval,
they are not. But there is often ambigious language in FARs about
whether a product needs to be manufactured under TSO approval or just
"Meets the requirements in TSO–xxx" to be installed. The later is the
case in FAR 91.225 that governs ADS-B carriage requirements. So
technically for a certified aircraft that leaves the A&P and maybe
FSDO to try to work out how to determine if something "Meets the
requirements in TSO–xxx" but is not yet TSO approved. If it gets to
the FSDO we can probably guess what their answer will be most of the
time. But with the current STC requirement policy from the FAA there
are no field approvals for installation of any ADS-B data-out
equipment on any certified aircraft (an STC cannot apply to an
experimental aircraft). And the FAA is extremely unlikely to approve
an STC that involved non actual-TSO approved ADS-B data-out equipment,
but like I've said before I really hope that work can be done in
parallel. It would be a very "brave" A&P who now tried to justify an
ADS-B data-out install as a minor modification to avoid doing even a
337.

Now the STC requirement is just an FAA approvals policy not a
regulation. (You can read it here
http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgPolicy.nsf/0/34a9674f068fb64d86257790006d038a/$FILE/Approval%20for%20ADS-B%20Out%20Systems.pdf).
The FAA could change policy tomorrow. They could let any non-IFR
aircraft use field approval, they could let any glider use field
approval. It might be reasonable for the industry to try to work with
the FAA to more aggressively shorten the time those kind of aircraft
require STC for installations.

***NavWorx equipment is available today and can be installed on both
experimental and certified aircraft when it meets “portable
installation guidelines.***

No argument on NavWorx's claim here about "experimental aircraft", I
beleive they can have Navworx equipment, both their ADS-B receive only
and ADS-B transceiver equipment installed.

You cannot install an ADS-B data-out system that required connection
to an aircraft static source and installation of transmitter antennas
and call it a "portable install". NavWorx also makes portable UAT data-
in (receive only) products and I parse their statement here as "well
if you can't install one of our UAT transceivers because of this STC
requirement in a certified aircraft then you can at least install one
of our UAT receivers and still get some ADS_B benefits". Remember they
are only saying "equipment". Misquoting what's his name: It depends on
what the meaning of "equipment" is.

As a reminder UAT data-in is only suitable receiving UAT direct
broadcasts from UAT data-out equipped aircraft and FIS-B (weather and
Notam etc. data). A UAT data-in receiver cannot receive ADS-R or FIS-B
reliably unless you have an UAT data-out transmitter in the aircraft,
or combined in a transceiver. BTW -- I would have said ADS-B data-out
in general there before which is technically correct but the FAA also
seems to be discouraging mixed UAT data-out and 1090ES data-in or visa-
versa installations, and not that they can regulate what portable
receiver devices you install if you want to but I want to know more
why the FAA believes this is important enough to caution against.

For the GA market it would be great if ADS-B vendors could talk about
the actual STCs they are working on for installation in certified
aircraft. But I expect they see that as a competitive secret. I'd like
the FAA to talk about how long they expect the STC requirement to
remain in place and/or (since picking a time my be impossible) some of
the milestones they want to see before lifting this requirement in the
hope that may help the industry work though this.

Again this stuff only applies to certified aircraft. Experimental
aircraft are free to install the NavWorx and other ADS-B data-out
devices. The caution there for GA aircraft is if that installation is
going to be used to meet the carriage mandate in
FAR 91.225 they _may_ need to do extra work (e.g. on use a fancy WAAS
GPS driving the data-out).

And remember the NavWorx transceivers are not practical for
isntallation in gliders today, they consume too much power and don't
interface to any popular glider traffic displays and other issues I've
flogged to death before here.

----

BTW to be clear as well on all these FIS-B and TIS-B services. They
currently should be available in (mopstly) east and west coast ARTCC
regions as a part of the essential services (TIS-B and FIS-B (Weather,
NOTAMS etc.) enroute rollout but integration for most TRACON/Terminal
infrastructure will not happen until through 2013. So check with your
local TRACON for when exactly they will have essential (FIS-B, TIS-B)
and critical (ADS-R and ATC surveillance) service available.
Unfortunately there seems no good FAA or ITT website that provides
schedules in a understandable format (if anybody knows one I'd love to
know). It seems some pilots are interpreting some information
available on-line as many regions have full ADS-B essential (TIS-B and
FIS-B)and critical (ATC surveillance and ADS-R) services available in
both enroute and terminal service areas.


Darryl

On Oct 29, 8:16*am, Mike Schumann
wrote:
On 10/28/2010 10:21 PM, Darryl Ramm wrote:
[snip]

You are confusing ADS-B and everything else under the "Nextgen" umbrella.

No. I am pointing out lots of the complexity in ADS-B comes from its
multiple applications for multiple different users seeking multiple
different benefits. Nextgen is the raison d'être for ADS-B and Nextgen
requirements have driven development of the underlying RTCA standards
etc.

ADS-B is fundamentally a very simple concept. *You have a GPS in your
airplane, and once a second you transmit your position and velocity
vector data. *On the receive side, you listen and receive everyone
else's position. *Additional data may also be available if you are
interested (weather, Notams, etc.).

Ah now I get it I'm looking at this all wrong. I'm trying to look at
things from a practical, what works, how it works, what can be used
together viewpoint... for now and in the future. But what we should be
focusing on instead is simple concepts--even when any cogent practical
thought shows the actual use of these technologies in actual scenarios
to save actual pilots lives is not simple.

Why don't you write those simple concepts down on a sheet of paper and
tape them inside your cockpit. That will draw no power, require no
space to install, require no third party display devices, have no
false alarm issue, have no compatibility requirements with current
glider equipment and require no FAA approval. And should the small
practical things happen of you get killed in a mid-air collision we
can tape those simple concepts inside your coffin.

ADS-B is basically the same as FLARM, except that FLARM also includes
collision avoidance features that need to be implemented externally to
the ADS-B transceiver, if the user desires this...

ADS-B is basically the same as FLARM for the purposes of making silly
debating points. The focus of most of the rest of us is what can most
practically/best be done to avoid mid-air collisions.

Darryl

On 10/29/2010 12:33 PM, kirk.stant wrote:
Mike, you have just confirmed what I just suspected. Again, ADS-b is
designed for keeping airplanes that want to stay apart, apart. And
yes, I understand exactly what the ground infrastructure is for, and
it's not gliders - It's for IFR air traffic control and GA planes
working their way through bad weather, checking on the latest NOTAMs
at their destination. Sure, "someone" could develop software and
hardware to use ADS-b to do what FLARM has been doing for the past 10
years, BUT THE CHANCE OF THAT HAPPENING IN THE NEAR FUTURE IS A CLOSE
APPROXIMATION OF ZERO!

Can't you understand that this isn't a zero sum game? NOTHING
prevents you from having FLARM now (in Europe) or next year (in the
US, hopefully) and later, if and when ADS-b becomes affordable and
useable in a glider cockpit, installing ADS-b in their glider. And
that even if the FAA gave a free UAT to every aircraft out there,
FLARM would still be useful in the glider community?

The two systems overlap each other, but occupy different requirement
niches.


Kirk
66

The ground infrastructure is for EVERYONE! Glider pilots are probably
not as interested in weather or NOTAMs. They are interested in seeing
Mode C / S equipped aircraft (both GA and Jets) in their vicinity. This
is the BIG reason you should care about ADS-B ground stations.

The PowerFLARM proponents claim that it will handled 1090ES ADS-B
Inputs. Does this include TIS-B data? What is the plan for PowerFLARM
equipped aircraft to transmit ADS-B Out data so that the TIS-B data is
visible? If PowerFLARM can do that, then it will be a killer product,
not just for the glider world, but also for GA in the US.

--
Mike Schumann

On Oct 29, 11:30*am, Mike Schumann
wrote:
On 10/29/2010 12:33 PM, kirk.stant wrote:



Mike, you have just confirmed what I just suspected. *Again, ADS-b is
designed for keeping airplanes that want to stay apart, apart. *And
yes, I understand exactly what the ground infrastructure is for, and
it's not gliders - It's for IFR air traffic control and GA planes
working their way through bad weather, checking on the latest NOTAMs
at their destination. Sure, "someone" could develop software and
hardware to use ADS-b to do what FLARM has been doing for the past 10
years, BUT THE CHANCE OF THAT HAPPENING IN THE NEAR FUTURE IS A CLOSE
APPROXIMATION OF ZERO!

Can't you understand that this isn't a zero sum game? *NOTHING
prevents you from having FLARM now (in Europe) or next year (in the
US, hopefully) and later, if and when ADS-b becomes affordable and
useable in a glider cockpit, installing ADS-b in their glider. *And
that even if the FAA gave a free UAT to every aircraft out there,
FLARM would still be useful in the glider community?

The two systems overlap each other, but occupy different requirement
niches.

Kirk
66

The ground infrastructure is for EVERYONE! *Glider pilots are probably
not as interested in weather or NOTAMs. *They are interested in seeing
Mode C / S equipped aircraft (both GA and Jets) in their vicinity. *This
is the BIG reason you should care about ADS-B ground stations.

The PowerFLARM proponents claim that it will handled 1090ES ADS-B
Inputs. *Does this include TIS-B data? *What is the plan for PowerFLARM
equipped aircraft to transmit ADS-B Out data so that the TIS-B data is
visible? *If PowerFLARM can do that, then it will be a killer product,
not just for the glider world, but also for GA in the US.

--
Mike Schumann

Ground infrastructure, once it is deployed and in-service, is for
everybody within the coverage volume of that infrastructure and who is
properly equipped to use it. Unfortunately those requirements will
exclude many gliders and popular glider locations which may makes it
less useful than the combination of Flarm (esp. for glider threats)
and PCAS (esp. for GA threats) in PowerFLARM for many of us - assuming
we can get good mutual equipage of Flarm products within the glider
community. But that seems off to a good start.

As has been discussed on r.a.s. already Flarm have talked about
PowerFLARM having a software update in 2011 that will support TIS-B.
Since this is of any interest in the USA only, requires currently
expensive and difficult to install ADS-B data-out equipment, and TIS-B
capability has limited deployment today I hope Flarm does not waste
any time working on TIS-B support before the product ships. It is easy
to understand why TIS-B needs more work - TIS-B service data has
relatively high positional uncertainty compared to Flarm or ADS-B
direct data because the target information is from an SSR radar (or
multilateration) source and radar scan time delays and position
extrapolation induced errors. Some traffic displays might well just
ignore all this and treat the position of a TIS-B threat as if it is
highly precise and that could be a problem when you get close.... who
knows how all those third party PDA traffic display/processor devices
handle this today. I expect with Flarms focus on the glider market
they will work to get this right for our use.

To see threat aircraft via TIS-B the GBT ground infrastructure needs
to be deployed and integrated into the appropriate enroute and
terminal radar facilities and the threat aircraft need to to be within
that SSR radar coverage and your glider needs to be equipped with ADS-
B data-out (so the ADS-B ground infrastructure knows you are there)
and you obviously need some form of ADS-B data-in and TIS-B capable
traffic display/threat processing (PowerFLARM will do the later two
after the software update). If you do all that you will "see" TIS-B
data for all transponder equipped threats within +/-3,500' and a 15nm
cylinder around your aircraft's position. You may also see other TIS-B
"threats" within service volumes around other ADS-B data-out equipped
"client" aircraft but pilots really must not rely on that. I point it
out to explain to people why you may see a TIS-B threat on an ADS-B
data-in only system and that threat may magically appear and dissapear
from the display (but still be a very real threat)--if that happens
with PowerFLARM when used without ADS-B data-out at least the PCAS
should be screaming at you as the threat gets close.

TIS-B requires the deployment of FAA ground infrasttucutre and
integration of that with the appropriate radar facilities (enroute and
terminal facilities are rolled out differently). That won't be
complete for several more years. Pilots need to understand the
situation for their local area -- is TIS-B available and from enroute
and/or terminal radar and what are the coverage volumes for those
services.

I have no doubt that the directional and longer range capabilites of
TIS-B compared to PCAS is a nice thing. But given the current cost and
other issues around equipping with ADS-B data-out as well as ADS-B
data-in to receive TIS-B service makes this impractical at least for
the near future for most glider pilots. Most of my time talking with
pilots about TIS-B is to correct misunderstandings they have, for
example assuming that ADS-B data-in alone will provide TIS-B in their
cockpit.

Given the limited SSR coverage in many places we fly gliders and lack
of GBT (ADS-B ground based transceiver) coverage at many GA airports
and many popular gliding locations I do not see TIS-B as a replacement
for PCAS. I've seen lots of alerts on my Zaon MRX when definitively
outside of SSR coverage (presumably those transponders were being
interrogated by TCAS/TCAD equipped aircraft). A bit of the irony then
is that the PowerFLARM by being 1090ES not UAT based can easily
include PCAS capability and if a pilots wants to install 1090ES data-
out in future (as prices fall, products become more practical and
installation issues go away as they will) then that is a great
option.

Also just to point out a timing issue -- worrying about TIS-B for
gliders only makes sense if adoption becomes important within a
certain time window - for most after ~2013 as widescale TIS-B service
infrastructure deploy but before 2020 since after that TIS-B service
is expcted be turned off since the assumption is it won't be needed as
all those transponder equipped aircraft will be transmitting ADS-B
data-out and link-layer conversion vis ADS-R will provide all that is
needed. ADS-R will provide wider area and more accurate coverage than
TIS-B. I hope cost and install issues do decrease - I want to play
with all this with 1090ES data-out from a Trig TT21 in my (certified)
glider with PowerFLARM doing 1090ES data-in.

In discussing ADS-B ground infrastructure being "for everybody" it is
also worth noting that most deployments of ADS-B ground infrastructure
in the USA today do not include the ADS-R service yet and this
"critical service" (in FAA speak) will take several more years to roll
out widely. So if you have a UAT receiver you won't see any of those
1090ES data-out equipped airliners etc. who are amongst the early ADS-
B data-out adopters and of interest to many of us in location like
Reno. With a PowerFLARM with 1090ES data-in we see those directly, but
similarly those of us with PowerFLARM and its 1090ES data-in won't see
anybody with UAT data-out (until the ADS-R service is locally
available and then only when we are within coverage of the GBT - and
that will have significant coverage gaps for us to worry about,
especially close to terrain).

Again with any complex system like this the devil is in the practical
details...

Darryl

On 10/29/2010 2:51 PM, Darryl Ramm wrote:
On Oct 29, 11:30 am, Mike
wrote:
On 10/29/2010 12:33 PM, kirk.stant wrote:



Mike, you have just confirmed what I just suspected. Again, ADS-b is
designed for keeping airplanes that want to stay apart, apart. And
yes, I understand exactly what the ground infrastructure is for, and
it's not gliders - It's for IFR air traffic control and GA planes
working their way through bad weather, checking on the latest NOTAMs
at their destination. Sure, "someone" could develop software and
hardware to use ADS-b to do what FLARM has been doing for the past 10
years, BUT THE CHANCE OF THAT HAPPENING IN THE NEAR FUTURE IS A CLOSE
APPROXIMATION OF ZERO!

Can't you understand that this isn't a zero sum game? NOTHING
prevents you from having FLARM now (in Europe) or next year (in the
US, hopefully) and later, if and when ADS-b becomes affordable and
useable in a glider cockpit, installing ADS-b in their glider. And
that even if the FAA gave a free UAT to every aircraft out there,
FLARM would still be useful in the glider community?

The two systems overlap each other, but occupy different requirement
niches.

Kirk
66

The ground infrastructure is for EVERYONE! Glider pilots are probably
not as interested in weather or NOTAMs. They are interested in seeing
Mode C / S equipped aircraft (both GA and Jets) in their vicinity. This
is the BIG reason you should care about ADS-B ground stations.

The PowerFLARM proponents claim that it will handled 1090ES ADS-B
Inputs. Does this include TIS-B data? What is the plan for PowerFLARM
equipped aircraft to transmit ADS-B Out data so that the TIS-B data is
visible? If PowerFLARM can do that, then it will be a killer product,
not just for the glider world, but also for GA in the US.

--
Mike Schumann

Ground infrastructure, once it is deployed and in-service, is for
everybody within the coverage volume of that infrastructure and who is
properly equipped to use it. Unfortunately those requirements will
exclude many gliders and popular glider locations which may makes it
less useful than the combination of Flarm (esp. for glider threats)
and PCAS (esp. for GA threats) in PowerFLARM for many of us - assuming
we can get good mutual equipage of Flarm products within the glider
community. But that seems off to a good start.

As has been discussed on r.a.s. already Flarm have talked about
PowerFLARM having a software update in 2011 that will support TIS-B.
Since this is of any interest in the USA only, requires currently
expensive and difficult to install ADS-B data-out equipment, and TIS-B
capability has limited deployment today I hope Flarm does not waste
any time working on TIS-B support before the product ships. It is easy
to understand why TIS-B needs more work - TIS-B service data has
relatively high positional uncertainty compared to Flarm or ADS-B
direct data because the target information is from an SSR radar (or
multilateration) source and radar scan time delays and position
extrapolation induced errors. Some traffic displays might well just
ignore all this and treat the position of a TIS-B threat as if it is
highly precise and that could be a problem when you get close.... who
knows how all those third party PDA traffic display/processor devices
handle this today. I expect with Flarms focus on the glider market
they will work to get this right for our use.

To see threat aircraft via TIS-B the GBT ground infrastructure needs
to be deployed and integrated into the appropriate enroute and
terminal radar facilities and the threat aircraft need to to be within
that SSR radar coverage and your glider needs to be equipped with ADS-
B data-out (so the ADS-B ground infrastructure knows you are there)
and you obviously need some form of ADS-B data-in and TIS-B capable
traffic display/threat processing (PowerFLARM will do the later two
after the software update). If you do all that you will "see" TIS-B
data for all transponder equipped threats within +/-3,500' and a 15nm
cylinder around your aircraft's position. You may also see other TIS-B
"threats" within service volumes around other ADS-B data-out equipped
"client" aircraft but pilots really must not rely on that. I point it
out to explain to people why you may see a TIS-B threat on an ADS-B
data-in only system and that threat may magically appear and dissapear
from the display (but still be a very real threat)--if that happens
with PowerFLARM when used without ADS-B data-out at least the PCAS
should be screaming at you as the threat gets close.

TIS-B requires the deployment of FAA ground infrasttucutre and
integration of that with the appropriate radar facilities (enroute and
terminal facilities are rolled out differently). That won't be
complete for several more years. Pilots need to understand the
situation for their local area -- is TIS-B available and from enroute
and/or terminal radar and what are the coverage volumes for those
services.

I have no doubt that the directional and longer range capabilites of
TIS-B compared to PCAS is a nice thing. But given the current cost and
other issues around equipping with ADS-B data-out as well as ADS-B
data-in to receive TIS-B service makes this impractical at least for
the near future for most glider pilots. Most of my time talking with
pilots about TIS-B is to correct misunderstandings they have, for
example assuming that ADS-B data-in alone will provide TIS-B in their
cockpit.

Given the limited SSR coverage in many places we fly gliders and lack
of GBT (ADS-B ground based transceiver) coverage at many GA airports
and many popular gliding locations I do not see TIS-B as a replacement
for PCAS. I've seen lots of alerts on my Zaon MRX when definitively
outside of SSR coverage (presumably those transponders were being
interrogated by TCAS/TCAD equipped aircraft). A bit of the irony then
is that the PowerFLARM by being 1090ES not UAT based can easily
include PCAS capability and if a pilots wants to install 1090ES data-
out in future (as prices fall, products become more practical and
installation issues go away as they will) then that is a great
option.

Also just to point out a timing issue -- worrying about TIS-B for
gliders only makes sense if adoption becomes important within a
certain time window - for most after ~2013 as widescale TIS-B service
infrastructure deploy but before 2020 since after that TIS-B service
is expcted be turned off since the assumption is it won't be needed as
all those transponder equipped aircraft will be transmitting ADS-B
data-out and link-layer conversion vis ADS-R will provide all that is
needed. ADS-R will provide wider area and more accurate coverage than
TIS-B. I hope cost and install issues do decrease - I want to play
with all this with 1090ES data-out from a Trig TT21 in my (certified)
glider with PowerFLARM doing 1090ES data-in.

In discussing ADS-B ground infrastructure being "for everybody" it is
also worth noting that most deployments of ADS-B ground infrastructure
in the USA today do not include the ADS-R service yet and this
"critical service" (in FAA speak) will take several more years to roll
out widely. So if you have a UAT receiver you won't see any of those
1090ES data-out equipped airliners etc. who are amongst the early ADS-
B data-out adopters and of interest to many of us in location like
Reno. With a PowerFLARM with 1090ES data-in we see those directly, but
similarly those of us with PowerFLARM and its 1090ES data-in won't see
anybody with UAT data-out (until the ADS-R service is locally
available and then only when we are within coverage of the GBT - and
that will have significant coverage gaps for us to worry about,
especially close to terrain).

Again with any complex system like this the devil is in the practical
details...

Darryl

What evidence do you have that there are plans to turn off TIS-B after
2020? The current 2020 ADS-B out rules only require equipage in certain
airspace environments. There are lots of areas where there will be
ADS-B ground station and radar coverage, where ADS-B out equipage will
be optional, and there may be a significant number of Mode C/S
transponder equipped GA aircraft still flying around without ADS-B.

While there are a lot of remote areas of the country where TIS-B will
not be available to glider pilots, there are also a lot of areas close
to metro areas where a lot of recreational pilots fly where ADS-B ground
stations with TIS-B support are or will be turned on a lot quicker than
you are leading people to believe.

I would certainly encourage the PowerFLARM people to figure out how to
support TIS-B as quickly as possible (which of course will require them
to figure out a practical, cost effective way for pilots to add ADS-B
Out equipment to their cockpits). If this becomes a practical product
feature, it would be a huge advance over PCAS and would open up the GA
market to their system, which is 10x larger than the glider market in
the US.

--
Mike Schumann

Darryl, by the way, the USAF (and I assume USN/Marines/Army) is in the
process of installing Mode S (with 1090 ES) in many (if not all) of
it's planes. C-17s are already using this mode in Europe, as can be
seen on the sites that show Mode S tracks. And I personally know that
F-15Es are being equipped with Mode S.

What this means is that there is the potential for using the
PowerFLARM 1090 ES detection capability to provide accurate and timely
warning of military aircraft - such as fighters on low level routes,
and in MOAs. That would be awesome - I'm sure we have all been
surprised by a pair of fighters at some time.

What we may need is for SSA to push the DOD to require all military
aircraft equipped with Mode S transponders to use them at all times
when practicable and explain why.

This capability in itself makes a PowerFLARM a necessity in some
areas!

Cheers,

Kirk

"Mike Schumann" wrote in message
...
What evidence do you have that there are plans to turn off TIS-B after 2020?
Some TIS stations are already gone. See this AOPA blurb:
http://www.aopa.org/whatsnew/newsite...051101tis.html Google for more.

Vaughn

On Oct 29, 2:24*pm, Mike Schumann
wrote:
On 10/29/2010 2:51 PM, Darryl Ramm wrote:



On Oct 29, 11:30 am, Mike
wrote:
On 10/29/2010 12:33 PM, kirk.stant wrote:

Mike, you have just confirmed what I just suspected. *Again, ADS-b is
designed for keeping airplanes that want to stay apart, apart. *And
yes, I understand exactly what the ground infrastructure is for, and
it's not gliders - It's for IFR air traffic control and GA planes
working their way through bad weather, checking on the latest NOTAMs
at their destination. Sure, "someone" could develop software and
hardware to use ADS-b to do what FLARM has been doing for the past 10
years, BUT THE CHANCE OF THAT HAPPENING IN THE NEAR FUTURE IS A CLOSE
APPROXIMATION OF ZERO!

Can't you understand that this isn't a zero sum game? *NOTHING
prevents you from having FLARM now (in Europe) or next year (in the
US, hopefully) and later, if and when ADS-b becomes affordable and
useable in a glider cockpit, installing ADS-b in their glider. *And
that even if the FAA gave a free UAT to every aircraft out there,
FLARM would still be useful in the glider community?

The two systems overlap each other, but occupy different requirement
niches.

Kirk
66

The ground infrastructure is for EVERYONE! *Glider pilots are probably
not as interested in weather or NOTAMs. *They are interested in seeing
Mode C / S equipped aircraft (both GA and Jets) in their vicinity. *This
is the BIG reason you should care about ADS-B ground stations.

The PowerFLARM proponents claim that it will handled 1090ES ADS-B
Inputs. *Does this include TIS-B data? *What is the plan for PowerFLARM
equipped aircraft to transmit ADS-B Out data so that the TIS-B data is
visible? *If PowerFLARM can do that, then it will be a killer product,
not just for the glider world, but also for GA in the US.

--
Mike Schumann

Ground infrastructure, once it is deployed and in-service, is for
everybody within the coverage volume of that infrastructure and who is
properly equipped to use it. Unfortunately those requirements will
exclude many gliders and popular glider locations which may makes it
less useful than the combination of Flarm (esp. for glider threats)
and PCAS (esp. for GA threats) in PowerFLARM for many of us - assuming
we can get good mutual equipage of Flarm products within the glider
community. But that seems off to a good start.

As has been discussed on r.a.s. already Flarm have talked about
PowerFLARM having a software update in 2011 that will support TIS-B.
Since this is of any interest in the USA only, requires currently
expensive and difficult to install ADS-B data-out equipment, and TIS-B
capability has limited deployment today I hope Flarm does not waste
any time working on TIS-B support before the product ships. It is easy
to understand why TIS-B needs more work - TIS-B service data has
relatively high positional uncertainty compared to Flarm or ADS-B
direct data because the target information is from an SSR radar (or
multilateration) source and radar scan time delays and position
extrapolation induced errors. Some traffic displays might well just
ignore all this and treat the position of a TIS-B threat as if it is
highly precise and that could be a problem when you get close.... who
knows how all those third party PDA traffic display/processor devices
handle this today. I expect with Flarms focus on the glider market
they will work to get this right for our use.

To see threat aircraft via TIS-B the GBT ground infrastructure needs
to be deployed and integrated into the appropriate enroute and
terminal radar facilities and the threat aircraft need to to be within
that SSR radar coverage and your glider needs to be equipped with ADS-
B data-out (so the ADS-B ground infrastructure knows you are there)
and you obviously need some form of ADS-B data-in and TIS-B capable
traffic display/threat processing (PowerFLARM will do the later two
after the software update). If you do all that you will "see" TIS-B
data for all transponder equipped threats within +/-3,500' and a 15nm
cylinder around your aircraft's position. You may also see other TIS-B
"threats" within service volumes around other ADS-B data-out equipped
"client" aircraft but pilots really must not rely on that. I point it
out to explain to people why you may see a TIS-B threat on an ADS-B
data-in only system and that threat may magically appear and dissapear
from the display (but still be a very real threat)--if that happens
with PowerFLARM when used without ADS-B data-out at least the PCAS
should be screaming at you as the threat gets close.

TIS-B requires the deployment of FAA ground infrasttucutre and
integration of that with the appropriate radar facilities (enroute and
terminal facilities are rolled out differently). That won't be
complete for several more years. Pilots need to understand the
situation for their local area -- is TIS-B available and from enroute
and/or terminal radar and what are the coverage volumes for those
services.

I have no doubt that the directional and longer range capabilites of
TIS-B compared to PCAS is a nice thing. But given the current cost and
other issues around equipping with ADS-B data-out as well as ADS-B
data-in to receive TIS-B service makes this impractical at least for
the near future for most glider pilots. Most of my time talking with
pilots about TIS-B is to correct misunderstandings they have, for
example assuming that ADS-B data-in alone will provide TIS-B in their
cockpit.

Given the limited SSR coverage in many places we fly gliders and lack
of GBT (ADS-B ground based transceiver) coverage at many GA airports
and many popular gliding locations I do not see TIS-B as a replacement
for PCAS. I've seen lots of alerts on my Zaon MRX when definitively
outside of SSR coverage (presumably those transponders were being
interrogated by TCAS/TCAD equipped aircraft). A bit of the irony then
is that the PowerFLARM by being 1090ES not UAT based can easily
include PCAS capability and if a pilots wants to install 1090ES data-
out in future (as prices fall, products become more practical and
installation issues go away as they will) then that is a great
option.

Also just to point out a timing issue -- worrying about TIS-B for
gliders only makes sense if adoption becomes important within a
certain time window - for most after ~2013 as widescale TIS-B service
infrastructure deploy but before 2020 since after that TIS-B service
is expcted be turned off since the assumption is it won't be needed as
all those transponder equipped aircraft will be transmitting ADS-B
data-out and link-layer conversion vis ADS-R will provide all that is
needed. ADS-R will provide wider area and more accurate coverage than
TIS-B. I hope cost and install issues do decrease - I want to play
with all this with 1090ES data-out from a Trig TT21 in my (certified)
glider with PowerFLARM doing 1090ES data-in.

In discussing ADS-B ground infrastructure being "for everybody" it is
also worth noting that most deployments of ADS-B ground infrastructure
in the USA today do not include the ADS-R service yet and this
"critical service" (in FAA speak) will take several more years to roll
out widely. So if you have a UAT receiver you won't see any of those
1090ES data-out equipped airliners etc. who are amongst the early ADS-
B data-out adopters and of interest to many of us in location like
Reno. With a PowerFLARM with 1090ES data-in we see those directly, but
similarly those of us with PowerFLARM and its 1090ES data-in won't see
anybody with UAT data-out (until the ADS-R service is locally
available and then only when we are within coverage of the GBT - and
that will have significant coverage gaps for us to worry about,
especially close to terrain).

Again with any complex system like this the devil is in the practical
details...

Darryl

What evidence do you have that there are plans to turn off TIS-B after
2020? *The current 2020 ADS-B out rules only require equipage in certain
airspace environments. *There are lots of areas where there will be
ADS-B ground station and radar coverage, where ADS-B out equipage will
be optional, and there may be a significant number of Mode C/S
transponder equipped GA aircraft still flying around without ADS-B.

While there are a lot of remote areas of the country where TIS-B will
not be available to glider pilots, there are also a lot of areas close
to metro areas where a lot of recreational pilots fly where ADS-B ground
stations with TIS-B support are or will be turned on a lot quicker than
you are leading people to believe.

I would certainly encourage the PowerFLARM people to figure out how to
support TIS-B as quickly as possible (which of course will require them
to figure out a practical, cost effective way for pilots to add ADS-B
Out equipment to their cockpits). *If this becomes a practical product
feature, it would be a huge advance over PCAS and would open up the GA
market to their system, which is 10x larger than the glider market in
the US.

--
Mike Schumann

The FAA has long stated their desire to decommission TIS-B some time
after 2020. There were objections to this in the comments to the NPRM
and in the final ADS-B rule making document the FAA promised it "will
evaluate the benefits of continuing TIS–B past the 2020 rule
compliance date" but I parse that as a non-committal committal and I
believe from other information this is still the goal. If you have
different information please let us know.

Remember also the cost saving from decommissioning of some existing
primary radar and SSR infrastructure is a part of what is driving the
cost justification for the ADS-B part of Nextgen. So you would loose
those source of TIS-B input data. By no means is all that SSR
infrastructure being proposed for decommissioning, but enough terminal
coverage is likely to be removed to be significant. And it may be an
interesting political juggling act for the FAA to claim to want to
turn off significant SSR radar infrastructure on on hand and about in
parallel want to keep alive TIS-B than would need input from those
sources. I have concerns about the uncompromising of terminal primary
radar and SSR infrastructure both from a redundancy and domestic
airspace national security virewpoints.

I'm not trying to lead anybody to think anything about schedules,
beyond saying that full deployment is scheduled for 2013. The fact
alone that ADS-R is virtually non-existent is a surprise for most
pilots--an important issue. Pilots need to check locally for the
details of what and when services are being deployed they can use. I
don't think most pilots hear about ADS-B and think en-route vs.
terminal vs. essential services vs. critical service deployment but
again because all this is complex they need to be thinking about that.
But what is the point of arguing, your the biggest proponent of this
stuff being used in the short term--maybe you could help explain the
USA ADS-B roll-out/schedule (in practical detail not concept) to help
people make equipage decisions.

Darryl

On Oct 27, 7:45*am, Kevin Christner wrote:
You are confusing cause and effect. *Your CHOICE to take more risk
CAUSES you to wear a parachute. *Your CHOICE to fly in competition
will CAUSE (force) you to use a FLARM. *You made choices independent
of equipment. *The equipment didnt cause you to take more risk.

A parachute strapped to my back may cause me to decide to spin down at
the end of a local soaring flight if I happen to have some altitude to
waste. Lack of a parachute will cause me to pull the brakes in such a
situation.

Just an example.

B.