Transponder TT21 versus TT22 - Considerations

[WaltWX[_2_]]

Just send off this question to Trig's North American Support. After having a telcon with him today regarding these issues, he stated that Trig has verbally told him that the TT21 would NOT be compliant for the ADS-B out mandate in 2020. This was based on some recent conversation with the FAA dealing with the ADS-B out program. He recommended that the question be passed on to Trig so they can give their formal reply:


Bruce Grammon
TRIG Support North America
Mid-Continent Instruments and Avionics

Bruce,

I'm a pilot with plans on installing the outstanding Trig transponder in my sailplane for flying in the Western United States where altitudes 15,000 to 18,000 frequently occur. But, I'm uncertain which model I should buy. My considerations:

1) I fly above 15K msl frequently; Is there any regulatory or practical reason to use the higher power TT22?

2) Cost is a consideration. Gliders are not mandated to use transponder below Class A airspace (excepting Class B and C). Nonetheless, I consider it a safety issue and morally correct to avoid mid air collisions with airliners.

3) Power consumption is a factor. What is the average power use increase using the TT22 versus the TT21?

4) Should the FAA change their mind regarding ADS-B out compliance and require it for gliders, can the TT21 be used for ADS-B out in the future?

Please forward these questions to Trig to help me and fellow glider pilots make the right decision on selecting Trig transponders.

Walter Rogers "WX"

[Darryl Ramm]

By all means get clarification on the point he was making, which to put it clearly is that Trig TT-21 is not TSO-C166b certified, whereas the Trig TT-31 and TT-22 are. Trig are usually remarkably responsive.

However a really hard/most expensive issue you face if intending to meet the 2020 carriage specifications (start at AC 20-165A) has nothing to do with any of the questions asked. It's meeting the requirements for a IFR/WAAS TSO-C145c (or similar) GPS source and finding somebody who can work with a FSDO on field approval (which the FAA would ideally like based on a prior STC, which there were none for gliders... but hopefully you start with the same GPS source and 1090ES data-out capable transponder installed via prior STC in some GA aircraft and check in with the FSDO folks first). That TSO-C145c GPS receiver will currently cost you more than a new Trig TT22.

If your glider is experimental then it may be all moot, if you just want to say "play" with ADS-B data-out then you can likely install a non-compliant system with a COTS GPS. You might get a friendly letter from the FAA pointing out you are flying around with a non-complaint system. And whether you have a fully TSO-166b complaint transponder may not be relevant. Lots of things to discuss there with any vendor before trying to do that.

Now if you ask any avionics manufacturer what power-transponder you should install and state you fly above 15,000' expect to be pointed at regulations that state you are required to use a 250W transponder, especially when its clear you intend to copy the world on the answers... even if in practice it mike make no difference.

If you fly in busy airspace, with airliners and fast jets etc. Please install a transponder. Whether it is a Trig T-21 or TT-22 has really no difference for the usefulness of that transponder. If you intend in future to go though all the money, complexity and hassle (uh why?) of installing ADS-B data-out as well then the question about TT-22 TSO-C166b certification may become relevant.

If "cost is a consideration" then that question likely answers itself -- save your money and forget doing ADS-B anything. And my question for folks who worry too much about ADS-B anything starts with why exactly do you want it/what extra service/capability do you expect to receive from having ADS-B data-out or in....

[Ventus2NZ]

http://www.aeroshop.eu/en/funkwerk-tm250-traffic-monitor.html

Does any one know if the unit in the link above will interface with the Trig transponders for ADSB?

[Darryl Ramm]

On Tuesday, January 20, 2015 at 3:51:37 PM UTC-8, Ventus2NZ wrote:
> http://www.aeroshop.eu/en/funkwerk-tm250-traffic-monitor.html
>
> Does any one know if the unit in the link above will interface with the Trig transponders for ADSB?

And here we go. What exactly are you trying to achieve? no
"interface with" tells us nothing. Where are you? To meet what exact regulation/requirement or technical goal (e.g. I want my buddies with PowerFLARM ADS-B 1090ES data-in to see me)?

A string will "interface with" a tin can... the results may or may not be what you want.

Are are in New Zealand? The USA or elsewhere? If in the USA are you flying a certified aircraft? Especially if in the USA... the system you pointed to is *not* a WAAS/IFR complaint GPS and cannot be used to meet USA 2020 ADS-B Out carriage requirements (but we have no clue if that is relevant to what you are trying to do or not...).

[Dave Springford]

It is my understanding that EASA approval exists for connecting non-certified GPS to mode S transponders to generate the ADS-B out data. In particular, the Garrecht VT-01 is approved in this manner and I think the Trig as well.

Since there are reciprocal agreements between EASA and other CAA's, the EASA approval should allow this practice in countries that reciprocate with EASA.

[Darryl Ramm]

On Tuesday, January 20, 2015 at 4:26:05 PM UTC-8, Dave Springford wrote:
> It is my understanding that EASA approval exists for connecting non-certified GPS to mode S transponders to generate the ADS-B out data. In particular, the Garrecht VT-01 is approved in this manner and I think the Trig as well.
>
> Since there are reciprocal agreements between EASA and other CAA's, the EASA approval should allow this practice in countries that reciprocate with EASA.

In a word NO. In two words HELL NO.

The NEMA GPS source used by a VT-01 does not meet any RTCA or EASA specification, and neither is is required to for it's intended (glider/light aircraft VFR) use in Europe.

There is no specific EASA requirement the VT-01 is required to meet for it's intended use, and in general it's worth being aware that EASA does not have an equivalent to the blanket FAA ADS-B mandate that is coming in 2020 (which gliders are exempt from). The relevant starting point is EASA AMC 20-24 (2008) which requires fit in new aircraft starting 2015 and retrofit in existing aircraft by 2017. But this *only* affects aircraft with MTOW greater than 5700kg or maximum cruising TAS greater than 250kts.

So there is no approval this meets, there is no relevant reciprocal agreement (reciprocity of ADS-B requirements for airliners etc. in EASA and the FAA is a long seperate discussion...), there is no nothing, there is no way any NEMA GPS source can meet the current FAA ADS-B Out GPS source requirements. And again, if you want to understand ADS-B Out approval in the USA start at FAA AC 20-165A.

[Darryl Ramm]

And to be clear the VT-01 does not claim to meet EASA AMC 20-24, and even if the transponder itself did, any system trying to use a NEMA GPS source could not.

[[email protected]]

Also worth noting that "does it work" is not the same as "is it approved." ADS-B approved installations are by specific equipment for specific certified aircraft. At present, I'm not aware of any approved installations for specific gliders. Please correct me if I am wrong.

[Darryl Ramm]

On Tuesday, January 20, 2015 at 5:29:06 PM UTC-8, wrote:
> Also worth noting that "does it work" is not the same as "is it approved." ADS-B approved installations are by specific equipment for specific certified aircraft. At present, I'm not aware of any approved installations for specific gliders. Please correct me if I am wrong.

And "does it work" required careful definition of what exactly "work" means.. (e.g. would ATC see you at all? Would you receive ground based ADS-R and TIS-B service in the USA, etc.). Connecting two boxes together and transmitting something that is a flavor of ADS-B Out is a very low-bar, likely uselessly low.

And the corollary to "is it approved" is can I as a pilot or A&P get into trouble if I just go ahead and do it if it is not approved... and in the USA in a certified aircraft the answer to that question is very much yes.

USA ADS-B Out approvals are available now via FAA field approval, so in that sense they are based on specific instances of installs, as I already said the FAA wants that to be based on existing STCs, again all covered in AC 20-165A. The STCs that the FAA want to based that on were often AML (approved model list) STCs, so covering more than one specific aircraft type/install situation. No STCs/AML STCs exist for gliders that I am aware of, but solving that problem starts with a call to the friendly staff at your local FSDO, and being willing to write a large check for a suitable GPS and to pay the A&P/IA/shop to do the install and spend time dealing with the field approval. Where folks go into this with their eyes open and have good contacts at their local FSDO and involvement from the vendors I expect this to be quite doable in a certified glider. The willingness to spend $$$ and a reason to bother are all anybody need to get started...

[WaltWX[_2_]]

Daryl,

First, I have no intention of equipping with ADS-B out and agree that there is little or no value to gliders. My interest in having a Trig that is compliant for ADS-B out is just in case FAA changes their mind and mandates it for gliders in 2020. Yes, the complexity of certification and cost are prohibitive. I'm just trying to consider whether it's worth it for an extra $300 and slightly higher power usage to be "ready".

My main interest is to protect myself against fast jets and airliners etc in busy airspace.

Thanks for all your explanations and background in this discussion... although it sure makes a decision on which unit to purchase difficult. I agree the TT21 is probably all I need for the time being.

Walt Rogers WX

> If you fly in busy airspace, with airliners and fast jets etc. Please install a transponder. Whether it is a Trig T-21 or TT-22 has really no difference for the usefulness of that transponder. If you intend in future to go though all the money, complexity and hassle (uh why?) of installing ADS-B data-out as well then the question about TT-22 TSO-C166b certification may become relevant.
>

[[email protected]]

On Tuesday, January 20, 2015 at 11:57:33 PM UTC-5, WaltWX wrote:
> Daryl,
>
> First, I have no intention of equipping with ADS-B out and agree that there is little or no value to gliders. My interest in having a Trig that is compliant for ADS-B out is just in case FAA changes their mind and mandates it for gliders in 2020. Yes, the complexity of certification and cost are prohibitive. I'm just trying to consider whether it's worth it for an extra $300 and slightly higher power usage to be "ready".
>
> My main interest is to protect myself against fast jets and airliners etc in busy airspace.
>
> Thanks for all your explanations and background in this discussion... although it sure makes a decision on which unit to purchase difficult. I agree the TT21 is probably all I need for the time being.
>
> Walt Rogers WX
>
> > If you fly in busy airspace, with airliners and fast jets etc. Please install a transponder. Whether it is a Trig T-21 or TT-22 has really no difference for the usefulness of that transponder. If you intend in future to go though all the money, complexity and hassle (uh why?) of installing ADS-B data-out as well then the question about TT-22 TSO-C166b certification may become relevant.
> >

There is a lot of value in outfitting a glider with ADS-B OUT. Specifically, this is required to reliably receive TIS-B traffic from ADS-B ground stations.

There are a lot of lower cost ADS-B OUT solutions in the pipeline. At OSHKOSH last summer L3 announced a complete 2020 compliant ADS-B IN/OUT solution that was suppose to cost $2-3K. This system was suppose to ship by the end of 2014. I suspect that there will be a number of significant additional product introductions at the next OSHKOSH show.

ADS-B is going to be a very important collision avoidance tool for those of us who fly recreationally near major metropolitan airports, where the mid-air threats are not just gliders, but other GA and airline aircraft.

[Darryl Ramm]

On Tuesday, January 20, 2015 at 9:55:35 PM UTC-8, wrote:
> On Tuesday, January 20, 2015 at 11:57:33 PM UTC-5, WaltWX wrote:
> > Daryl,
> >
> > First, I have no intention of equipping with ADS-B out and agree that there is little or no value to gliders. My interest in having a Trig that is compliant for ADS-B out is just in case FAA changes their mind and mandates it for gliders in 2020. Yes, the complexity of certification and cost are prohibitive. I'm just trying to consider whether it's worth it for an extra $300 and slightly higher power usage to be "ready".
> >
> > My main interest is to protect myself against fast jets and airliners etc in busy airspace.
> >
> > Thanks for all your explanations and background in this discussion... although it sure makes a decision on which unit to purchase difficult. I agree the TT21 is probably all I need for the time being.
> >
> > Walt Rogers WX
> >
> > > If you fly in busy airspace, with airliners and fast jets etc. Please install a transponder. Whether it is a Trig T-21 or TT-22 has really no difference for the usefulness of that transponder. If you intend in future to go though all the money, complexity and hassle (uh why?) of installing ADS-B data-out as well then the question about TT-22 TSO-C166b certification may become relevant.
> > >
>
> There is a lot of value in outfitting a glider with ADS-B OUT. Specifically, this is required to reliably receive TIS-B traffic from ADS-B ground stations.
>
> There are a lot of lower cost ADS-B OUT solutions in the pipeline. At OSHKOSH last summer L3 announced a complete 2020 compliant ADS-B IN/OUT solution that was suppose to cost $2-3K. This system was suppose to ship by the end of 2014. I suspect that there will be a number of significant additional product introductions at the next OSHKOSH show.
>
> ADS-B is going to be a very important collision avoidance tool for those of us who fly recreationally near major metropolitan airports, where the mid-air threats are not just gliders, but other GA and airline aircraft.

Technology like TIS-B as an aspiration are great, who would not love to see all transponder equipped aircraft nearby, but it's got to be affordable, its got to have low-power consumption and it's got to be compatible with what is in glider cockpits already, and pilots have to understand some restrictions on how the technology actually works/what it actually provides.

TIS-B probably has little interest to most glider pilots. It requires you to equip with a currently expensive ADS-B data-out system, also have ADS-B data-in that is TIS-B compatible (PowerFLARM unfortunately is not) and then only shows you other aircraft within coverage of FAA ground radar, with radar and system time delay limited positional accuracy of that other traffic. And all this that once these so far-mythical affordable systems become available and installable in a glider would then only be that useful for a short time until much of the GA fleet equip with ADS-B out, and ideally 1090ES Out (which it looks like most GA folks will... and many airliners and fast jets already are..). Which by then makes TIS-B uninteresting for gliders as you would hopefully receive much better traffic information via ADS-B/1090ES direct in your good old PowerFLARM.

L3 seems to be stumbling a bit with the Lynx system (what you are referring to), they are around 6 months late on making available specifications they promised half way back in 2014, so while it would be great if they did something I'd not hold my breath. And any system is dead in the water for gliders unless it has low-power consumption.. so that will be the first spec to look at. And prices I've seen mentioned for Lynx starting around $2k for a 1090ES Out with a GPS source would be impressive.. but that starting price does not include the ADS-B In option... I've not seen any indication of pricing that includes that (maybe it is $3k bit that just seems pretty-amazingly cheap for such a system from L3). And besides power the next thing is can the traffic display be compatible with what is used in a glider... most gliders don't have space for yet another traffic display, and if anything need ADS-B data output in a Flarm compatible way to be displayed on a display they already have in the panel. And then if you do happen to have a PowerFLARM already there is a slight annoyance of how to deal with two sources feeding a display, and worse how to deduplicate traffic warnings, but all doable if somebody wants to build a custom box/software to do this, but it is not clear who that would be...

It does look like Lynx (or well it's Optional ADS-B in part) and other ADS-B In systems from folks like Garmin are going the right way and doing dual-link 1090ES and UAT In. The mess the FAA created with dual-link basically ends up with the only reliable way to see all ADS-B traffic is to carry both a UAT and 1090ES receiver. And with much of the GA fleet lightly to be transmitting 1090ES the FAA could have saved all this effort and just gone 1090ES only. Sad really how badly this was messed up.

Equipping with a plain old a Mode C or Mode S transponder still can give you pretty good bang for the buck if you fly near lots of GA traffic, and PCAS in PowerFLARM can be a nice low cost/low complexity help for you to be aware of that traffic. Equipping with a transponder lets ATC see you, can let GA aircraft "see" you if they are equipped with PCAS, TCAD, Mode S TIS (if your local approach SSR provides that) and full ADS-B systems in the right circumstances via TIS-B. Of course if L3 or others ever ships a 1090ES Out system with built-in IFR GPS source for the same price as a Mode-S transponder alone then and it's low enough power for a glider then I expect folks to go that route. Multiple vendors are talking about single box ADS-B Out solutions, ultimately it's a required step to get ownership and install costs down in GA aircraft that don't already have a IFR GPS systems.

[[email protected]]

This is the best answer on this thread.

Having flown a turbocharged airplane equipped with TCAS in the teens and low FLs around the west, I missed a lot of aircraft visually that came up In the screen. Flying without it feels like I'm flung blind.

--bob

[Mike Schumann[_2_]]

On Wednesday, January 21, 2015 at 2:06:21 AM UTC-5, Darryl Ramm wrote:
> On Tuesday, January 20, 2015 at 9:55:35 PM UTC-8, wrote:
> > On Tuesday, January 20, 2015 at 11:57:33 PM UTC-5, WaltWX wrote:
> > > Daryl,
> > >
> > > First, I have no intention of equipping with ADS-B out and agree that there is little or no value to gliders. My interest in having a Trig that is compliant for ADS-B out is just in case FAA changes their mind and mandates it for gliders in 2020. Yes, the complexity of certification and cost are prohibitive. I'm just trying to consider whether it's worth it for an extra $300 and slightly higher power usage to be "ready".
> > >
> > > My main interest is to protect myself against fast jets and airliners etc in busy airspace.
> > >
> > > Thanks for all your explanations and background in this discussion... although it sure makes a decision on which unit to purchase difficult. I agree the TT21 is probably all I need for the time being.
> > >
> > > Walt Rogers WX
> > >
> > > > If you fly in busy airspace, with airliners and fast jets etc. Please install a transponder. Whether it is a Trig T-21 or TT-22 has really no difference for the usefulness of that transponder. If you intend in future to go though all the money, complexity and hassle (uh why?) of installing ADS-B data-out as well then the question about TT-22 TSO-C166b certification may become relevant.
> > > >
> >
> > There is a lot of value in outfitting a glider with ADS-B OUT. Specifically, this is required to reliably receive TIS-B traffic from ADS-B ground stations.
> >
> > There are a lot of lower cost ADS-B OUT solutions in the pipeline. At OSHKOSH last summer L3 announced a complete 2020 compliant ADS-B IN/OUT solution that was suppose to cost $2-3K. This system was suppose to ship by the end of 2014. I suspect that there will be a number of significant additional product introductions at the next OSHKOSH show.
> >
> > ADS-B is going to be a very important collision avoidance tool for those of us who fly recreationally near major metropolitan airports, where the mid-air threats are not just gliders, but other GA and airline aircraft.
>
> Technology like TIS-B as an aspiration are great, who would not love to see all transponder equipped aircraft nearby, but it's got to be affordable, its got to have low-power consumption and it's got to be compatible with what is in glider cockpits already, and pilots have to understand some restrictions on how the technology actually works/what it actually provides.
>
> TIS-B probably has little interest to most glider pilots. It requires you to equip with a currently expensive ADS-B data-out system, also have ADS-B data-in that is TIS-B compatible (PowerFLARM unfortunately is not) and then only shows you other aircraft within coverage of FAA ground radar, with radar and system time delay limited positional accuracy of that other traffic. And all this that once these so far-mythical affordable systems become available and installable in a glider would then only be that useful for a short time until much of the GA fleet equip with ADS-B out, and ideally 1090ES Out (which it looks like most GA folks will... and many airliners and fast jets already are..). Which by then makes TIS-B uninteresting for gliders as you would hopefully receive much better traffic information via ADS-B/1090ES direct in your good old PowerFLARM.
>
> L3 seems to be stumbling a bit with the Lynx system (what you are referring to), they are around 6 months late on making available specifications they promised half way back in 2014, so while it would be great if they did something I'd not hold my breath. And any system is dead in the water for gliders unless it has low-power consumption.. so that will be the first spec to look at. And prices I've seen mentioned for Lynx starting around $2k for a 1090ES Out with a GPS source would be impressive.. but that starting price does not include the ADS-B In option... I've not seen any indication of pricing that includes that (maybe it is $3k bit that just seems pretty-amazingly cheap for such a system from L3). And besides power the next thing is can the traffic display be compatible with what is used in a glider... most gliders don't have space for yet another traffic display, and if anything need ADS-B data output in a Flarm compatible way to be displayed on a display they already have in the panel. And then if you do happen to have a PowerFLARM already there is a slight annoyance of how to deal with two sources feeding a display, and worse how to deduplicate traffic warnings, but all doable if somebody wants to build a custom box/software to do this, but it is not clear who that would be...
>
> It does look like Lynx (or well it's Optional ADS-B in part) and other ADS-B In systems from folks like Garmin are going the right way and doing dual-link 1090ES and UAT In. The mess the FAA created with dual-link basically ends up with the only reliable way to see all ADS-B traffic is to carry both a UAT and 1090ES receiver. And with much of the GA fleet lightly to be transmitting 1090ES the FAA could have saved all this effort and just gone 1090ES only. Sad really how badly this was messed up.
>
> Equipping with a plain old a Mode C or Mode S transponder still can give you pretty good bang for the buck if you fly near lots of GA traffic, and PCAS in PowerFLARM can be a nice low cost/low complexity help for you to be aware of that traffic. Equipping with a transponder lets ATC see you, can let GA aircraft "see" you if they are equipped with PCAS, TCAD, Mode S TIS (if your local approach SSR provides that) and full ADS-B systems in the right circumstances via TIS-B. Of course if L3 or others ever ships a 1090ES Out system with built-in IFR GPS source for the same price as a Mode-S transponder alone then and it's low enough power for a glider then I expect folks to go that route. Multiple vendors are talking about single box ADS-B Out solutions, ultimately it's a required step to get ownership and install costs down in GA aircraft that don't already have a IFR GPS systems.

It is very unfortunate that PowerFlarm doesn't support TIS-B. That would make it a great solution for glider pilots who want all the advantages of ADS-B IN and also have FLARM capability.

The PCAS functionality in PowerFlarm doesn't come close to matching the functionality you get with TIS-B. You have no idea where the conflict aircraft is, only its altitude and approximate distance (based on some very crude received power level measurements). That's a whole lot different than TIS-B which shows you the absolute position of the target to the same resolution that is available on an air traffic controller's radar screen.

While TIS-B will eventually disappear after we have universal deployment of ADS-B OUT, we still have ~6 years before that happens.

Every glider pilot is going to have to make their own decisions on the optimal solution they want to deploy. If you are a contest pilot flying in remote locations where radar coverage is spotty, TIS-B might be of limited utility and FLARM may be more important. If you are a recreational pilot flying near a major metropolitan airport, getting an ADS-B solution that supports TIS-B, even if it just interfaces with ForeFlight on your iPhone, could save your life.

[Peter von Tresckow]

Mike Schumann > wrote:
> On Wednesday, January 21, 2015 at 2:06:21 AM UTC-5, Darryl Ramm wrote:
>> On Tuesday, January 20, 2015 at 9:55:35 PM UTC-8, wrote:
>>> On Tuesday, January 20, 2015 at 11:57:33 PM UTC-5, WaltWX wrote:
>>>> Daryl,
>>>>
>>>> First, I have no intention of equipping with ADS-B out and agree that
>>>> there is little or no value to gliders. My interest in having a Trig
>>>> that is compliant for ADS-B out is just in case FAA changes their mind
>>>> and mandates it for gliders in 2020. Yes, the complexity of
>>>> certification and cost are prohibitive. I'm just trying to consider
>>>> whether it's worth it for an extra $300 and slightly higher power usage to be "ready".
>>>>
>>>> My main interest is to protect myself against fast jets and airliners
>>>> etc in busy airspace.
>>>>
>>>> Thanks for all your explanations and background in this discussion...
>>>> although it sure makes a decision on which unit to purchase difficult.
>>>> I agree the TT21 is probably all I need for the time being.
>>>>
>>>> Walt Rogers WX
>>>>
>>>>> If you fly in busy airspace, with airliners and fast jets etc. Please
>>>>> install a transponder. Whether it is a Trig T-21 or TT-22 has really
>>>>> no difference for the usefulness of that transponder. If you intend
>>>>> in future to go though all the money, complexity and hassle (uh why?)
>>>>> of installing ADS-B data-out as well then the question about TT-22
>>>>> TSO-C166b certification may become relevant.
>>>>>
>>>
>>> There is a lot of value in outfitting a glider with ADS-B OUT.
>>> Specifically, this is required to reliably receive TIS-B traffic from
>>> ADS-B ground stations.
>>>
>>> There are a lot of lower cost ADS-B OUT solutions in the pipeline. At
>>> OSHKOSH last summer L3 announced a complete 2020 compliant ADS-B IN/OUT
>>> solution that was suppose to cost $2-3K. This system was suppose to
>>> ship by the end of 2014. I suspect that there will be a number of
>>> significant additional product introductions at the next OSHKOSH show.
>>>
>>> ADS-B is going to be a very important collision avoidance tool for
>>> those of us who fly recreationally near major metropolitan airports,
>>> where the mid-air threats are not just gliders, but other GA and airline aircraft.
>>
>> Technology like TIS-B as an aspiration are great, who would not love to
>> see all transponder equipped aircraft nearby, but it's got to be
>> affordable, its got to have low-power consumption and it's got to be
>> compatible with what is in glider cockpits already, and pilots have to
>> understand some restrictions on how the technology actually works/what
>> it actually provides.
>>
>> TIS-B probably has little interest to most glider pilots. It requires
>> you to equip with a currently expensive ADS-B data-out system, also have
>> ADS-B data-in that is TIS-B compatible (PowerFLARM unfortunately is not)
>> and then only shows you other aircraft within coverage of FAA ground
>> radar, with radar and system time delay limited positional accuracy of
>> that other traffic. And all this that once these so far-mythical
>> affordable systems become available and installable in a glider would
>> then only be that useful for a short time until much of the GA fleet
>> equip with ADS-B out, and ideally 1090ES Out (which it looks like most
>> GA folks will... and many airliners and fast jets already are..). Which
>> by then makes TIS-B uninteresting for gliders as you would hopefully
>> receive much better traffic information via ADS-B/1090ES direct in your
>> good old PowerFLARM.
>>
>> L3 seems to be stumbling a bit with the Lynx system (what you are
>> referring to), they are around 6 months late on making available
>> specifications they promised half way back in 2014, so while it would be
>> great if they did something I'd not hold my breath. And any system is
>> dead in the water for gliders unless it has low-power consumption.. so
>> that will be the first spec to look at. And prices I've seen mentioned
>> for Lynx starting around $2k for a 1090ES Out with a GPS source would be
>> impressive.. but that starting price does not include the ADS-B In
>> option... I've not seen any indication of pricing that includes that
>> (maybe it is $3k bit that just seems pretty-amazingly cheap for such a
>> system from L3). And besides power the next thing is can the traffic
>> display be compatible with what is used in a glider... most gliders
>> don't have space for yet another traffic display, and if anything need
>> ADS-B data output in a Flarm compatible way to be displayed on a display
>> they already have in the panel. And then if you do happen to have a
>> PowerFLARM already there is a slight annoyance of how to deal with two
>> sources feeding a display, and worse how to deduplicate traffic
>> warnings, but all doable if somebody wants to build a custom
>> box/software to do this, but it is not clear who that would be...
>>
>> It does look like Lynx (or well it's Optional ADS-B in part) and other
>> ADS-B In systems from folks like Garmin are going the right way and
>> doing dual-link 1090ES and UAT In. The mess the FAA created with
>> dual-link basically ends up with the only reliable way to see all ADS-B
>> traffic is to carry both a UAT and 1090ES receiver. And with much of the
>> GA fleet lightly to be transmitting 1090ES the FAA could have saved all
>> this effort and just gone 1090ES only. Sad really how badly this was messed up.
>>
>> Equipping with a plain old a Mode C or Mode S transponder still can give
>> you pretty good bang for the buck if you fly near lots of GA traffic,
>> and PCAS in PowerFLARM can be a nice low cost/low complexity help for
>> you to be aware of that traffic. Equipping with a transponder lets ATC
>> see you, can let GA aircraft "see" you if they are equipped with PCAS,
>> TCAD, Mode S TIS (if your local approach SSR provides that) and full
>> ADS-B systems in the right circumstances via TIS-B. Of course if L3 or
>> others ever ships a 1090ES Out system with built-in IFR GPS source for
>> the same price as a Mode-S transponder alone then and it's low enough
>> power for a glider then I expect folks to go that route. Multiple
>> vendors are talking about single box ADS-B Out solutions, ultimately
>> it's a required step to get ownership and install costs down in GA
>> aircraft that don't already have a IFR GPS systems.
>
> It is very unfortunate that PowerFlarm doesn't support TIS-B. That would
> make it a great solution for glider pilots who want all the advantages of
> ADS-B IN and also have FLARM capability.
>
> The PCAS functionality in PowerFlarm doesn't come close to matching the
> functionality you get with TIS-B. You have no idea where the conflict
> aircraft is, only its altitude and approximate distance (based on some
> very crude received power level measurements). That's a whole lot
> different than TIS-B which shows you the absolute position of the target
> to the same resolution that is available on an air traffic controller's radar screen.
>
> While TIS-B will eventually disappear after we have universal deployment
> of ADS-B OUT, we still have ~6 years before that happens.
>
> Every glider pilot is going to have to make their own decisions on the
> optimal solution they want to deploy. If you are a contest pilot flying
> in remote locations where radar coverage is spotty, TIS-B might be of
> limited utility and FLARM may be more important. If you are a
> recreational pilot flying near a major metropolitan airport, getting an
> ADS-B solution that supports TIS-B, even if it just interfaces with
> ForeFlight on your iPhone, could save your life.

Actually TIS-B only functions if the ground station sees an ADS-B out
target. They then compute any target in your "donut" and transmit that data
out. No ADS-B out no TIS-B for you. You can still piggyback on someone
else's signal but TIS-B isn't a broadcast of all targets all the time.

Peter

[Mike Schumann[_2_]]

On Wednesday, January 21, 2015 at 4:47:34 PM UTC-5, vontresc wrote:
>
> > On Wednesday, January 21, 2015 at 2:06:21 AM UTC-5, Darryl Ramm wrote:
> >> On Tuesday, January 20, 2015 at 9:55:35 PM UTC-8, wrote:
> >>> On Tuesday, January 20, 2015 at 11:57:33 PM UTC-5, WaltWX wrote:
> >>>> Daryl,
> >>>>
> >>>> First, I have no intention of equipping with ADS-B out and agree that
> >>>> there is little or no value to gliders. My interest in having a Trig
> >>>> that is compliant for ADS-B out is just in case FAA changes their mind
> >>>> and mandates it for gliders in 2020. Yes, the complexity of
> >>>> certification and cost are prohibitive. I'm just trying to consider
> >>>> whether it's worth it for an extra $300 and slightly higher power usage to be "ready".
> >>>>
> >>>> My main interest is to protect myself against fast jets and airliners
> >>>> etc in busy airspace.
> >>>>
> >>>> Thanks for all your explanations and background in this discussion...
> >>>> although it sure makes a decision on which unit to purchase difficult.
> >>>> I agree the TT21 is probably all I need for the time being.
> >>>>
> >>>> Walt Rogers WX
> >>>>
> >>>>> If you fly in busy airspace, with airliners and fast jets etc. Please
> >>>>> install a transponder. Whether it is a Trig T-21 or TT-22 has really
> >>>>> no difference for the usefulness of that transponder. If you intend
> >>>>> in future to go though all the money, complexity and hassle (uh why?)
> >>>>> of installing ADS-B data-out as well then the question about TT-22
> >>>>> TSO-C166b certification may become relevant.
> >>>>>
> >>>
> >>> There is a lot of value in outfitting a glider with ADS-B OUT.
> >>> Specifically, this is required to reliably receive TIS-B traffic from
> >>> ADS-B ground stations.
> >>>
> >>> There are a lot of lower cost ADS-B OUT solutions in the pipeline. At
> >>> OSHKOSH last summer L3 announced a complete 2020 compliant ADS-B IN/OUT
> >>> solution that was suppose to cost $2-3K. This system was suppose to
> >>> ship by the end of 2014. I suspect that there will be a number of
> >>> significant additional product introductions at the next OSHKOSH show.
> >>>
> >>> ADS-B is going to be a very important collision avoidance tool for
> >>> those of us who fly recreationally near major metropolitan airports,
> >>> where the mid-air threats are not just gliders, but other GA and airline aircraft.
> >>
> >> Technology like TIS-B as an aspiration are great, who would not love to
> >> see all transponder equipped aircraft nearby, but it's got to be
> >> affordable, its got to have low-power consumption and it's got to be
> >> compatible with what is in glider cockpits already, and pilots have to
> >> understand some restrictions on how the technology actually works/what
> >> it actually provides.
> >>
> >> TIS-B probably has little interest to most glider pilots. It requires
> >> you to equip with a currently expensive ADS-B data-out system, also have
> >> ADS-B data-in that is TIS-B compatible (PowerFLARM unfortunately is not)
> >> and then only shows you other aircraft within coverage of FAA ground
> >> radar, with radar and system time delay limited positional accuracy of
> >> that other traffic. And all this that once these so far-mythical
> >> affordable systems become available and installable in a glider would
> >> then only be that useful for a short time until much of the GA fleet
> >> equip with ADS-B out, and ideally 1090ES Out (which it looks like most
> >> GA folks will... and many airliners and fast jets already are..). Which
> >> by then makes TIS-B uninteresting for gliders as you would hopefully
> >> receive much better traffic information via ADS-B/1090ES direct in your
> >> good old PowerFLARM.
> >>
> >> L3 seems to be stumbling a bit with the Lynx system (what you are
> >> referring to), they are around 6 months late on making available
> >> specifications they promised half way back in 2014, so while it would be
> >> great if they did something I'd not hold my breath. And any system is
> >> dead in the water for gliders unless it has low-power consumption.. so
> >> that will be the first spec to look at. And prices I've seen mentioned
> >> for Lynx starting around $2k for a 1090ES Out with a GPS source would be
> >> impressive.. but that starting price does not include the ADS-B In
> >> option... I've not seen any indication of pricing that includes that
> >> (maybe it is $3k bit that just seems pretty-amazingly cheap for such a
> >> system from L3). And besides power the next thing is can the traffic
> >> display be compatible with what is used in a glider... most gliders
> >> don't have space for yet another traffic display, and if anything need
> >> ADS-B data output in a Flarm compatible way to be displayed on a display
> >> they already have in the panel. And then if you do happen to have a
> >> PowerFLARM already there is a slight annoyance of how to deal with two
> >> sources feeding a display, and worse how to deduplicate traffic
> >> warnings, but all doable if somebody wants to build a custom
> >> box/software to do this, but it is not clear who that would be...
> >>
> >> It does look like Lynx (or well it's Optional ADS-B in part) and other
> >> ADS-B In systems from folks like Garmin are going the right way and
> >> doing dual-link 1090ES and UAT In. The mess the FAA created with
> >> dual-link basically ends up with the only reliable way to see all ADS-B
> >> traffic is to carry both a UAT and 1090ES receiver. And with much of the
> >> GA fleet lightly to be transmitting 1090ES the FAA could have saved all
> >> this effort and just gone 1090ES only. Sad really how badly this was messed up.
> >>
> >> Equipping with a plain old a Mode C or Mode S transponder still can give
> >> you pretty good bang for the buck if you fly near lots of GA traffic,
> >> and PCAS in PowerFLARM can be a nice low cost/low complexity help for
> >> you to be aware of that traffic. Equipping with a transponder lets ATC
> >> see you, can let GA aircraft "see" you if they are equipped with PCAS,
> >> TCAD, Mode S TIS (if your local approach SSR provides that) and full
> >> ADS-B systems in the right circumstances via TIS-B. Of course if L3 or
> >> others ever ships a 1090ES Out system with built-in IFR GPS source for
> >> the same price as a Mode-S transponder alone then and it's low enough
> >> power for a glider then I expect folks to go that route. Multiple
> >> vendors are talking about single box ADS-B Out solutions, ultimately
> >> it's a required step to get ownership and install costs down in GA
> >> aircraft that don't already have a IFR GPS systems.
> >
> > It is very unfortunate that PowerFlarm doesn't support TIS-B. That would
> > make it a great solution for glider pilots who want all the advantages of
> > ADS-B IN and also have FLARM capability.
> >
> > The PCAS functionality in PowerFlarm doesn't come close to matching the
> > functionality you get with TIS-B. You have no idea where the conflict
> > aircraft is, only its altitude and approximate distance (based on some
> > very crude received power level measurements). That's a whole lot
> > different than TIS-B which shows you the absolute position of the target
> > to the same resolution that is available on an air traffic controller's radar screen.
> >
> > While TIS-B will eventually disappear after we have universal deployment
> > of ADS-B OUT, we still have ~6 years before that happens.
> >
> > Every glider pilot is going to have to make their own decisions on the
> > optimal solution they want to deploy. If you are a contest pilot flying
> > in remote locations where radar coverage is spotty, TIS-B might be of
> > limited utility and FLARM may be more important. If you are a
> > recreational pilot flying near a major metropolitan airport, getting an
> > ADS-B solution that supports TIS-B, even if it just interfaces with
> > ForeFlight on your iPhone, could save your life.
>
> Actually TIS-B only functions if the ground station sees an ADS-B out
> target. They then compute any target in your "donut" and transmit that data
> out. No ADS-B out no TIS-B for you. You can still piggyback on someone
> else's signal but TIS-B isn't a broadcast of all targets all the time.
>
> Peter

That's absolutely correct. That's why it is so important to get a cost effective ADS-B OUT solution. That's why products like L3's Lynx are so critical. It's going to be interesting to see what gets announced at this summer's Oshkosh.

[WaltWX[_2_]]

Here's the reply to my question from Trig. The TT21 does not comply with ADS-B for the 2020 Mandate.
__________________________________________

Dear Walter,

Thank you for your enquiry and for considering Trig.

1. There is no real practical reason to need a TT22, but there is unfortunately a regulatory reason; Our TT21 and TT22 transponders are certified to TSO-C112c and therefore the DO-181D document applies. DO-181D paragraph 1.4.5 states:

Two minimum peak output power levels are supported by this version of these MOPS, 125 watt (21.0 dBW), which is designated as Class 1 equipment, and 70 watts (18.5 dBW), which is designated as Class 2 equipment. For more information on output power levels, see §2.2.3.2.
Class 1 equipment is intended for use in aircraft that operate at altitudes above 15000 ft, or have a maximum cruising true airspeed in excess of 175 kt (324 km/h).
Class 2 equipment may be used in aircraft that operate at altitudes not exceeding 15000 ft, and have a maximum cruising true airspeed not exceeding 175 kt (324 km/h).

Given that you are flying above 15,000ft frequently, the Class 1 TT22 would be more suited to your needs.
2. Cost wise, it may vary slightly depending on the supplier, but the TT22 is usually about $200 more expensive. I would agree with you , I do think collision avoidance is worth being involved in.
3. Not a great deal more power consumption for TT22;
Typical Consumption (at 14 V) TT21 idle: 0.15 A active: 0.28 A
TT22 idle: 0.15A active: 0.34 A

4. To comply with the FAA's 2020 mandate for ADS-B Out a certified Class 1 transponder is required after 2020, so a TT21 would not give a certified ADS-B Out solution. If the FAA decide gliders need to transmit ADS-B out, the TT22 will meet all the requirements. You will need to connect a GPS to the TT22 which provides the positional information and the type of GPS will depend on what the FAA decide is required for gliders.
I would therefore conclude that the Trig TT22 would better satisfy your requirements. I hope this is helpful, but if you have any further questions please do not hesitate to ask.


Bruce Grammon
Trig Avionics Technical Support
Mid-Continent Instruments and Avionics
9400 E. 34th Street North
Wichita, KS 67226
(800) 821-1212 ph
(316) 630-0723 fx
www.mcico.com
www.trig-avionics.com