• If You Are Having Trouble Logging In with Your Old Username and Password, Please use this Forgot Your Password link to get re-established.
  • Hey! Be sure to login or register!

ADS-B Out -- The Study Begins

Darrel Starr

Registered User
Plymouth, MN
The mandate is to comply with ADS-B Out by January 2020 so I am aiming for the winter of 2017-18 to install a unit. I figure that the dust will settle by then and prices stabilize. By installing about 2 years early I will beat the last minute rush and I want the plane to be apart in the dead of winter. So I thought it would be a good time to start studying the hardware and get ready to really look over the hardware at Osh this year. I have a certified Super Cub that I wired myself (see complete diagram in the Members area) so I don't need an avionics shop mucking about in the innards of my plane -- just sell me the hardware and give me the installation guide.
As Mark Baker, head of AOPA, has said several times in speeches, "you don't have to have an avionics shop install the hardware, just install it and get an IA to sign it off".
Well, problem #1 -- all ADS-B Out manufacturers sell only through dealers (ie, Avionics shops). For certified aircraft, all of the big distribution houses; Aircraft Spruce, Saratoga, etc. will sell "install only" -- meaning that they ship your hardware to one of their approved avionics shops.
Problem #2, the manufacturers might or might not email an installation guide to be studied. L3 Lynx did email a guide, Garmin told me to go to a dealer. I called Aircraft Spruce who might have sent it to me IF I had been experimental, but not to an owner of a certified plane. Regardless, some of this documentation is seeping out into the Internet.
Mark Baker recently said that it was time to act now that ADS-B out is under $2000. But even he did not understand what the installations require because the L3 Lynx NGT-1000 he was touting that "only" costs $1600 (what Mark was fixated on) also requires a $1000 control head, about $600 in antennas and of course is sold only by avionics shops so add some more --- $5000 est. for the most basic system.
I'm new to this subject but it seems as though the manufacturers could make this easier and a lot less costly.
Perhaps some of you avionics guys can chime in.
Here is the AvWeb piece that debunks the $1600 ADS-B Out price.
http://www.avweb.com/blogs/insider/Is-ADS-B-About-to-Break-Loose-223555-1.html
In calling around to L3, Garmin and Aircraft Spruce it became obvious that the people on the phones didn't know much about the subject.
When you start to read about this topic, you will immediately run into the term "extended squitter". Here is the definition.
http://www.garmin.com/us/intheair/ads-b/squit/
Where to put the antennas? The small "L" band antenna (4 inches long) goes on the bottom of the plane, at least 20 inches away from the current transponder antenna but not more than 132 inches away so the ADS-B and synchronize code and elevation with the current mode c or s transponder. It must have a 12 to 18 inch radius ground plane and not be obstructed by the landing gear. So I will need to install a ground plane back about the middle of the fuselage belly and make it probably by using foil tape under the fabric and cheat on the width some because the airplane is not 24 inches wide at that point. The GPS antenna goes on top also on a ground plane of similar size -- probably on the left fuel tank cover -- the Comm antenna is on the right side cover. In the case of the $4000 (box only) Garmin GDL 84, a small set of lights are all that have to be installed in the panel, but the L3 control head takes up a (non existing in my plane) spare instrument hole. The GDL 84 will Bluetooth to an iPad but it is line of sight. Garmin told me not to put the 7 inch square box under the panel or in the baggage area, possibly best on the floor close to the panel -- not a very neat solution.
Anyway, that is what I think I have learned -- please feel free to correct and add more info if you can. I would like to see in writing where I can install this stuff with an IA signoff if I eventually get my hands on the hardware & install guide.
 
Thanks Darrel, That is a good summary. Perhaps the solution is to just tell an outfit like Aircraft Spruce that you have an experimental airplane. Make the installation yourself and deal with your IA. IF I allow myself to be drawn into this "capture and control" environment by our government, that is the route which I shall follow. I do not allow other fingers messing with my airplanes. Fool me once.........!
 
The problem is that probably only one in ten "mechanics"(both certified and not) who thinks he know how to install avionics actually does....... I thought I did 40 years ago, now I KNOW I don't!

This will very likely be a huge mess, everybody waits and not enough "real" avionics shops to get it done.

Me, If I'm still flying it will be out here in uncontrolled airspace...........
 
The winner will be the avionics company which develops a simple "plug and play" system. One box, one antenna and one compact panel unit. One A+ wire and a ground. In this day and age of micro electronics, it is a wonder that this has not yet been done. That is unless they all see big $$$ because of ADS-B being a federal mandate. I'm inclined to believe the latter.
 
Darrel,

Maybe this will fit your plans - even got an installation manual -£2100 ($3200) from one UK dealer. Nothing to say you can't install it yourself - only recommendation to do otherwise.

Frank
 
I have already been through a couple of ADS-B units as I learn how the system works and what is and is not desirable. I'll write a little synopses of what I have observed with how the system works and doesn't work.

There are a lot of installation rules for ADS-B units, especially with regards to antenna placement to avoid interference. However, it is important to remember that ADS-B out is the only part that is mandated and the only piece of the puzzle you need to have installed by an avionics shop if your plane is certificated (both of mine are Experimental). As long as you meet the criteria of staying below 18,000' and no international flights, I don't think it matters whether you have UAT (978Mhz) out or 1090Mhz ES (Mode S extended Squitter). Install the one that will be most economical for you.

UAT-Out
There are some complexities that come with installing UAT Out, which on the surface looks to be a simple install as it's just a magic box with a WASS III GPS and a transmitter antenna. However, the FAA decided the squawk code transmitted by the UAT device and the pressure altitude reported by the UAT device has to come from the same source as the pressure altitude and squawk code for the transponder. That is a change in the last year. In the last few months, we have started to see some units that will interrogate the transponder so the transponder will reply back to the UAT device with the sqauwk code and pressure altitude, which the UAT device will then include in it's output stream. My newest unit, which I installed 2 weeks, ago has this feature. Of course it turned out that while my old Terra transponder was acceptable to ATC, it was off frequency a bit, so the transponder and the UAT device wouldn't talk. So now my transponder is currently enjoying a vacation at the repair depot for a bench check and frequency alignment.

Some other UAT devices will allow you splice into your gray code wiring to pick up the pressure altitude, but I haven't resolved how they are to pick up the squawk code from an older transponder. Some newer mode C transponders have a data port so they can communicate directly with a UAT device.

1090ES-Out
Mode S with extended Squitter Output. As far as I know, this works well. Of course a Mode S transponder isn't cheap, and adding a WAAS III GPS source to it isn't cheap either. But sometimes it's just easier than trying to preserve your antique Mode C transponder and dealing with trying to get it to talk to your UAT device.

ADS-B In
There is no mandate for ADS-B in. But it is nice to have as it provides traffic (TIS-B), and weather (FIS-B). You can use a portable unit if you choose as there are no requirements. If I had this to do over again, I would not buy an integrated unit where the ADS-B In and Out are in the same box.

Single Band vs Dual Band ADS-B Receivers
This is where you have to read what the sales literature is not saying. Many ADS-B receivers out there are single band. Single band receivers receive only UAT traffic. When queried about 1090ES, the manufacture will tell you that the FAA will be providing the 1090ES traffic via the ADS-B tower (UAT), so you don't need a dual band receiver. So let's think about that statement as there are a lot of places this scenario can (and does) break down. The 1090ES traffic has to be seen by center's radar, then the data has to be transferred to the ADS-B tower, then if you are in range of the tower, it gets broadcast out to you as TIS-B traffic. Personally, I find that when approaching many airports that are not near major metropolitan areas, I get dropped off radar, and am out of range of an ADS-B tower. So effectively, when you are approaching a small airport, all the 1090-ES traffic will drop off your screen if you have a single band receiver. If you have a dual band receiver, you will receive UAT and 1090ES traffic directly. You still rely on radar and TIS-B service to display the Mode-C traffic.

This is another reason why one might want to consider using UAT out vs 1090-ES for their ADS-B out. Many of the ADS-B receivers being sold are only single band. If you install 1090-ES with your new Mode-S transponder, many of the receivers aren't going to see you directly, and not at all if you are low and out of sight of radar, or they are out of range from an ADS-B broadcast tower.

ADS-B Weather (FIS-B)
Not as crisp and clear as XM weather, and you only get an area limited to the region covered by the ADS-B tower(s) you are currently receiving for NEXRAD radar. However, I do find that when there is active weather in the area, the ADS-B tower updates the radar image at 3 minute intervals. If there isn't any active weather happening on NEXRAD, the images can get pretty stale. I find it good enough for weather avoidance and accurate enough to pick my way around cells. I don't penetrate weather and would not use it for such.

BTW, this setup is in my other Experimental. My SC clone only has a weather receiver as it's rare that I am high enough to deal with traffic other than in the pattern. So it's not a priority for me to equip my SC Clone with the full ADS-B suite.

Hope my learning experience is somewhat helpful to others that are trying to learn what does and doesn't work with ADS-B as the system certainly has it's strengths and weaknesses.

-Cub Builder
 
I.....the FAA decided the squawk code transmitted by the UAT device and the pressure altitude reported by the UAT device has to come from the same source as the pressure altitude and squawk code for the transponder. That is a change in the last year. ....
Some other UAT devices will allow you splice into your gray code wiring to pick up the pressure altitude, but I haven't resolved how they are to pick up the squawk code from an older transponder. Some newer mode C transponders have a data port so they can communicate directly with a UAT device. ...

Seems like I read about at least one ADS-B Out device that read the squawk & mode C your transponder was transmitting, either by clamping onto your txp antenna coax, or it had in and out connections for it.
 
Frank -- is that a Trig system?

Cub Builder, appreciate your real world experience.

hotrod 180 -- yes several systems use a 1030 MHz interrogation of the transponder to synchronize the transponder & ADS-B Out signal. That is the primary reason, as I understand it, for getting the distance from the existing transponder and the belly mounted ADS-B "L" antenna located more than 20 inches apart but not more than 132 inches or so.

Here is the Install Manual for the NGT-1000 that L3 Lynx sent to me;


I also contacted Appareo and got this reply:

Darrel, Thank you for contacting Appareo regarding the ESG! Unfortunately, we don't have any manuals completed on the ESG, However, if you go to http://www.appareo.com/aviation/ads-b-out/ and fill out your information in the "Pilots - Sign Up Here" link on the bottom of the page. This way you can receive certification specific to your aircraft type. We are in the process of building our dealer network, but hope there will be one that's convenient for you!

Happy Flying


Kal

Stratus Support
 

Attachments

Seems like I read about at least one ADS-B Out device that read the squawk & mode C your transponder was transmitting, either by clamping onto your txp antenna coax, or it had in and out connections for it.

Navworx ADS600-EXP and the latest model of the Skyguard EX (for Experimentals) both have that capability, as do a few others. NavWorx has a TSO model with the same capability. Skyguard is still working with the FAA to get a TSO approval.

Navworx has an inductance ring that clamps around your transponder coax to pick up the squawk and pressure altitude. It can also be connect to a transponder that has an RS-232 serial command port or an encoder with a serial pressure altitude output.

SkyguardTWX EX has an interrogator antenna that must be mounted in close proximity to the transponder antenna. I found that it works reliably at ~4 - 5 feet if the transponder is well tuned and not at all if the transponder is a tad off freq. It also has a port capable of talking to a transponder or encoder with serial RS-232 output capabilities.

There are undoubtely others as well that I haven't seen yet as this is going to be a pretty common setup.

-Cub Builder
 
I talked to Garmin yesterday and told them that there was a 2013 copy of the GDL88 installation guide on the Internet; today it was removed.
 
The mandate is to comply with ADS-B Out by January 2020 so I am aiming for the winter of 2017-18 to install a unit. I figure that the dust will settle by then and prices stabilize. By installing about 2 years early I will beat the last minute rush and I want the plane to be apart in the dead of winter. So I thought it would be a good time to start studying the hardware and get ready to really look over the hardware at Osh this year. I have a certified Super Cub that I wired myself (see complete diagram in the Members area) so I don't need an avionics shop mucking about in the innards of my plane -- just sell me the hardware and give me the installation guide.
As Mark Baker, head of AOPA, has said several times in speeches, "you don't have to have an avionics shop install the hardware, just install it and get an IA to sign it off".
Well, problem #1 -- all ADS-B Out manufacturers sell only through dealers (ie, Avionics shops). For certified aircraft, all of the big distribution houses; Aircraft Spruce, Saratoga, etc. will sell "install only" -- meaning that they ship your hardware to one of their approved avionics shops.
Problem #2, the manufacturers might or might not email an installation guide to be studied. L3 Lynx did email a guide, Garmin told me to go to a dealer. I called Aircraft Spruce who might have sent it to me IF I had been experimental, but not to an owner of a certified plane. Regardless, some of this documentation is seeping out into the Internet.
Mark Baker recently said that it was time to act now that ADS-B out is under $2000. But even he did not understand what the installations require because the L3 Lynx NGT-1000 he was touting that "only" costs $1600 (what Mark was fixated on) also requires a $1000 control head, about $600 in antennas and of course is sold only by avionics shops so add some more --- $5000 est. for the most basic system.
I'm new to this subject but it seems as though the manufacturers could make this easier and a lot less costly.
Perhaps some of you avionics guys can chime in.
Here is the AvWeb piece that debunks the $1600 ADS-B Out price.
http://www.avweb.com/blogs/insider/Is-ADS-B-About-to-Break-Loose-223555-1.html
In calling around to L3, Garmin and Aircraft Spruce it became obvious that the people on the phones didn't know much about the subject.
When you start to read about this topic, you will immediately run into the term "extended squitter". Here is the definition.
http://www.garmin.com/us/intheair/ads-b/squit/
Where to put the antennas? The small "L" band antenna (4 inches long) goes on the bottom of the plane, at least 20 inches away from the current transponder antenna but not more than 132 inches away so the ADS-B and synchronize code and elevation with the current mode c or s transponder. It must have a 12 to 18 inch radius ground plane and not be obstructed by the landing gear. So I will need to install a ground plane back about the middle of the fuselage belly and make it probably by using foil tape under the fabric and cheat on the width some because the airplane is not 24 inches wide at that point. The GPS antenna goes on top also on a ground plane of similar size -- probably on the left fuel tank cover -- the Comm antenna is on the right side cover. In the case of the $4000 (box only) Garmin GDL 84, a small set of lights are all that have to be installed in the panel, but the L3 control head takes up a (non existing in my plane) spare instrument hole. The GDL 84 will Bluetooth to an iPad but it is line of sight. Garmin told me not to put the 7 inch square box under the panel or in the baggage area, possibly best on the floor close to the panel -- not a very neat solution.
Anyway, that is what I think I have learned -- please feel free to correct and add more info if you can. I would like to see in writing where I can install this stuff with an IA signoff if I eventually get my hands on the hardware & install guide.

Can't respond to all the questions as I have not installed an L3 system yet.

But, as to the antennas. First, mounting any antenna on a fuel tank lid is a bad idea. When lightning strikes, it likes the tallest, pointiest, spot on the airplane to hit. That is why the AC 43 specifically warns not to mount an antenna on the cowl, as a strike could blind the pilot. If it's on a fuel tank lid, you have the chance to burn.

The good thing is that the ADS-B systems use L band antennas. Think transponder and DME antennas. L band and GPS antennas are small in size and have limited surface area which adds up to very little wind load, in flight. Which means they can be mounted without much of the doublers/bracing required for a rod type antenna. What you need to do (on fabric aircraft) is mount a square shaped mounting plate behind the fabric, to attach the antenna to. Use your imagination. Adel clamps, fabricated mounting tabs, even welding, if possible, to tie it into the available structure. Then fabricate a ground plane, on the inside of the fabric, CENTERED at the antenna. The install manual will tell you how big the ground plane needs to be. It can be made of aluminum or copper tape or brass or stainless screen. You can make the ground plane bigger but should never go smaller than required. Make sure you read the install instructions for the antenna. All L band antennas require a ground plain, but some GPS antennas don't require it. And as to the antennas themselves, some installations will give you multiple antennas to chose from, that will work with their system. Look closely at each antenna and chose one that will work best for you. They don't all mount the same.

As to the max distance between the ADS-B antenna and the transponder antenna, that only applies if you use the 'wireless' monitoring of the transponder signal. I'm installing a GSL-88D right now and it gives the option of the 'wireless' and hardwired connection between the ADS-B and the transponder. My recommendation is to use the hardwire every time. Eliminates the max/min antenna spread and makes the connection more reliable.

Installation information is hard to come by with new units, especially from the big players like Garmin. But that's one of the benefits of being in an organization like this. We share that info between us.

Web
 
Thanks Darrel.

One of the problems I see is that the idea of ADS-B is here, but the hardware (or software for that matter) is not, yet. This is probably going to turn out several iterations of ADS-B equipment, only a couple which will be blessed off as 'legal', after 2020. The rest of the guys that purchased and installed the non-'legal' stuff will be left out to dry.

The dual band systems, mentioned above (thanks Cub Builder) seem to make the most sense to me, although pretty spendy. And if you use a unit that talks to existing equipment through data lines like RS-232 or ARINC 429, the interconnects are down to a minimum. So if you have a high end GPS and a modern ELT/encoder, you simply connect them to the ADS-B with a twisted pair, or two, of data wires and set the programming.

But, as I said earlier, we'll have to wait and see if these units will still be legal after 2020 or if someone has come up with a unit that works even better.

Web
 
Web, nice to hear from someone actually in the business. As you said and as the AvWeb article said that I posted earlier, seems too early to jump. I will make the rounds at Oshkosh to see what is there and I'm curious if the population of aviators there are overrunning the booths to get information or not. So far in my limited study, I like the GDL 84 for both Out & In but need an install manual to learn more about it. It might be a lot wiser to just get the simplest Out unit and treat the In part as a totally separate thing.
 
My current plan is to purchase the Appareo. Here is why.

Don't need to buy a WAAS unit, it is integrated

1090 Out. That way if I go to Canada, I'm covered

Don't need permanent ADS-B In. I will always have some sort of unit like the Stratus to supply the IPad because as of right now you will be using a tablet for the future as your nav data source. That unit is not going away so while I like the Lynx, I cannot justify an extra 5500 dollars to deliver redundant wx and traffic data.

The Appareo unit will tightly integrate to the Stratus device.

Anybody see any holes in my thinking?
 
I have read that UAT with mode C will send an anonymous VFR code when squawking 1200, but ES with mode S will send the discreet aircraft ident no matter what the squawk. Is this correct? Could be important.
 
I just talked to my local Avionics Installer, R.C. Avionics at Anoka, ( Minneapolis, MN) http://www.rcavionics.com/home.html . The Manager, Al Akre, is willing to work with me to sell the hardware, make sure I install everything in the right places, inspect my work, test it and sign off on the installation. Sounds like it could work. They install mostly Garmin GDL 88 ADS-B Out but they were putting an L3 Lynx NGT-9000 into a C310 and seemed impressed with that unit. I agree it looks good but besides the $6800 price tag it is 0.175 taller than my King 76C transponder and would require major panel rework so, for me, that looks like too much trouble.
My next step is to try to get a handle on the pluses & minuses of the Garmin Flight Stream software vs the Foreflight VFR Pro because if I go with the Garmin GDL 84 I'm married to the Flight Stream software. I like my old Garmin 496 so I'm not anxious to give it up for navigation, maybe have both -- besides I need the 496 because it is the GPS input to my 406 ELT.
Any opinions on Flight Stream vs ForeFlight?
 
Last edited:
Frankly, as with some past FAA mandates, early adopters may be sorely disappointed, due to last minute changes in requirements. If I were thinking about an ADS-B unit for my plane (and I'm not), I'd wait as long as possible to ensure I didn't get bitten by the FAAs propensity to change specifications at the last moment.

There's no way I'd start shopping till at least 2019, if then. And that's still four years off. Don't get ahead of yourself.

MTV
 
I agree, Mike, that waiting is the thing to do but since I operate under a Mode C Veil, the compliance date probably looks a bit more real here so waiting until the last minute might not be the best policy in the metro areas.. This is an international agreement with Europe, I think, requiring this equipment in 2017 so I wouldn't bet on the FAA blinking this time around.
The other aspect is the value of the plane. If it turns out that I put the plane up for sale in the 2018 or later time frame, I'll have to discount the price if it is not compliant -- just another reason for being proactive.
 
Darrel,

You wouldn't have to discount that beautiful machine....just sell it to someone who'll fly it in the 95 % of US airspace where ADS-B won't be required.....that's the best airspace for a cub anyway.

MTV
 
I am under class B - the J-3 will, apparently, continue to fly daily unless the Director succeeds in his plans to make it a jetport only. The Decathlon will get parked until it all shakes out. I only fly it once a week anyway, and am usually slightly queasy after 20 minutes.

I agree with Mike. Shoot, I may have to move to the country anyway.
 
I am under class B - the J-3 will, apparently, continue to fly daily unless the Director succeeds in his plans to make it a jetport only. The Decathlon will get parked until it all shakes out. I only fly it once a week anyway, and am usually slightly queasy after 20 minutes.

I agree with Mike. Shoot, I may have to move to the country anyway.

bob,

Montana is full, but I hear North Dakota is nice.

MTV
 
Google recently announced they want to develop and use drones. Their announcement indicated that to make it work, they would need all their drones equipped with ADS-B and as many aircraft as possible would also need to be so equipped. They have teamed up Rockwell-Collins to produce a low cost ADS-B out unit. Their thinking is if all aircraft are equipped they will have a better chance of having their ADS-B equipped drones accepted into the air space system. I suspect that with their money behind it and their vision of a "for profit" system of drones they will make a $500 ADS-B unit a reality. At that price point, most of us who are on the fence, would likely have one installed. Based on that I will hold out for a couple years to see how it all shakes out with their research. Here's a link to one of the many articals discussing the Google-ADS-b interest. http://drone-rss.com/2015/03/google-producing-low-cost-adsb-transponders-for-drones/ Right now the development of ADS-B just seems too fluid to invest $6-$10K on system and start cutting up perfectly good panels to make it happen. Does the line "There's an App for that"
sound familiar? Who would have thought ten years ago that a really nice GPS navigation system could be carried on a device like an iPad. I really don't see ADS-B being any different than the evolution of GPS except that it likely will change at a much faster rate of change than that of GPS.
Marty57
 
I have read that UAT with mode C will send an anonymous VFR code when squawking 1200, but ES with mode S will send the discreet aircraft ident no matter what the squawk. Is this correct? Could be important.

Kind of. By default the UAT systems will send all of your data. However, and how this is accomplished is manufacturer dependent, they can be programmed to run in anonymous mode when you are squawking 1200. I haven't searched for that function on my unit yet, so haven't confirmed that it will function that way, but it's in the TSO.

-Cub Builder
 
....I suspect that with their money behind it and their vision of a "for profit" system of drones they will make a $500 ADS-B unit a reality. At that price point, most of us who are on the fence, would likely have one installed. Based on that I will hold out for a couple years to see how it all shakes out with their research. ..........

Now you're talking.
 
Frankly, as with some past FAA mandates, early adopters may be sorely disappointed, due to last minute changes in requirements. If I were thinking about an ADS-B unit for my plane (and I'm not), I'd wait as long as possible to ensure I didn't get bitten by the FAAs propensity to change specifications at the last moment.

There's no way I'd start shopping till at least 2019, if then. And that's still four years off. Don't get ahead of yourself.

MTV

Absolutely true. I bought a unit a year ago that met the rules at the time. The FAA "clarified" some of the rules, which meant my $1350 unit no longer met the rules for the 2020 mandate. The manufacturer offered me 50% back as an upgrade path to their new unit that meets the 2020 mandate for Experimental aircraft, in that it meets the performance standards in the current TSO data. I wouldn't be shocked to see another clarification between now and 2020, but I am enjoying the education and really like having traffic and weather in the plane (not my SC). I didn't buy the newer unit because I actually care about the 2020 mandate. I bought it because the old unit was broadcasting an incomplete data block in that it was only using GPS altitude and had no pressure altitude, so in effect, my altitudes were being reported incorrectly to others that were picking up my UAT out broadcast. Additionally, the new unit can sniff the squawk and pressure altitude from the transponder, so now I only need to set the squawk code in one place rather than two. Buying 2 units (so far) has been the cost of my education. But since I live in the E-AB world with two Experimental Aircraft, the cost for me to equip and test this equipment isn't so terribly prohibitive as it would be for a certificated aircraft.

-Cub Builder
 
.... I suspect that with their money behind it and their vision of a "for profit" system of drones they will make a $500 ADS-B unit a reality. At that price point, most of us who are on the fence, would likely have one installed. Based on that I will hold out for a couple years to see how it all shakes out with their research......

Now you're talking.
Won't it be something if we end up getting something good out of this Drone business?
 
Back
Top