A new twist: FAA to limit ADS-B/FIS B (traffic) in 2016

JHW said:
hyperbole, anyone? how does this affect your life in any way ? we've been flying for a century without a little screen in the cockpit showing us a subset of nearby traffic.
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I don't know about you, but my vision is near perfect and I have one heck of a time spotting planes until they are nearly right on top of me. See and avoid doesn't work so well when you don't see the other plane.

My primary point is that there is no technical reason that we can't receive all traffic around us with a very cheap ADS-B receiver. Feel free to correct me, if that's not the case.

"The FAA wants to encourage pilots to equip their airplane with ADS-B Out, so they’re requiring this equipment in order to receive traffic information. Their hope is that this incentive gets more airplanes flying with ADS-B Out, sooner. Many pilots think this is a bad idea, but regardless, it’s the way the system works right now."
 
Hmmmmm This looks like the thread I posted a few months ago when I mentioned someone who worked for the FAA told me they were tightening up requirements with regards to location/position and GPS type stuff. It was written off as total BS and more or less scoffed at as advice from some low level FAA employee passed through a noob pilot
 
you fool! You fell victim to one of the classic blunders - the most famous of which is "never get involved in a land war in Asia" - but only slightly less well known is this "Never believe the FAA when ADSB is on the line!!!"
 
ChemGuy said:
you fool! You fell victim to one of the classic blunders - the most famous of which is "never get involved in a land war in Asia" - but only slightly less well known is this "Never believe the FAA when ADSB is on the line!!!"
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Ha! If it wasn't a forum post they would have thrown tomatoes at me.... Yet here are.
 
ChemGuy said:
you fool! You fell victim to one of the classic blunders - the most famous of which is "never get involved in a land war in Asia" - but only slightly less well known is this "Never believe the FAA when ADSB is on the line!!!"
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:) Nice.
 
Challenged said:
I don't know about you, but my vision is near perfect and I have one heck of a time spotting planes until they are nearly right on top of me. See and avoid doesn't work so well when you don't see the other plane.
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If you're not close enough to see it, how much of a threat is it?? :dunno:

ATC calls out traffic all the time. I look, but if it's not filling my windshield I don't get overly panicked if I don't pick out an aircraft two miles away.
 
Challenged said:
My primary point is that there is no technical reason that we can't receive all traffic around us with a very cheap ADS-B receiver. Feel free to correct me, if that's not the case.
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That would be true if the FAA NextGen system didn't rely on moving from using primary radar to identify aircraft position to using self-reporting ADSB-out signals from aircraft.

You can't receive traffic with only a receiver if the overall system is dependent on aircraft transmitting their position in the first place.
 
This is good point Jim. That said, primary radar is still in use today and will be until the 2020 date arrives. Maybe I'm in the minority, but once I had installed ADS-B out in my plane I wonder how I did without it before, I felt much the same way after I installed my engine monitor. I just prefer to have as much information as possible I guess, and I think withholding traffic from pilots isn't a great safety advantage.
 
LDJones said:
If you're not close enough to see it, how much of a threat is it?? :dunno:

ATC calls out traffic all the time. I look, but if it's not filling my windshield I don't get overly panicked if I don't pick out an aircraft two miles away.
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For the win.... Well said.
 
A while ago I had a Mooney pass directly over me at, what I would guess was, 100 feet or so. I was at full cruise, and assume he was as well, so I imagine our closure rate was in the 350mph range. I had no time to do anything; it was an eye-opening experience, and this was with my wife and infant aboard, which made it even less of a fun feeling. I think there's only one or two mid-air collisions a month, however, so it's probably not worth doing anything about, even though we can.
 
We can also sit home on our couches and never have to worry about having a mid-air.
 
I don't lay awake at night thinking about mid air collisions, but if I could change a couple of settings on a server and know that it would save a fellow pilot's life, why would I not change a setting?
 
In light of all this, and since I haven't wrapped my head around it all yet, I have questions popping up in the noggin now.. One is.. will my GDL39 3D still be good to get ADS-B IN? I know it is not TSO'd but not sure about the certified status. I have used a straight GDL39 since 2012 and have enjoyed ADS-B IN for that long. About a year ago upgraded to the 3D version. I also run a GTX330ES for ADS-B OUT(since 2013).
 
There are two changes taking place. They only affect certain uncertified ADS-B Out systems.

First an explanation of the issue. Uncertified ADS-B Out systems with SDA or SIL values of zero are not visible to certified ADS-B In systems. Portable units are required to broadcast an SDA and SIL of zero, for example the Skyguard. Currently the Skyguard is provided with client services, which means it will get the ground station to provide TISB and ADSR services. However, a client does not have a TISB generated on its behalf, after all, it knows where it is or can be received via air to air broadcast. So since a TISB is not generated for a client such as a Skyguard and the air to air may not be displayed by a certified system such as a GNS/W, GTN, G500/600 and a GDL88. This makes the Skyguard a cloaking device, turn it on and it is invisible to certified aircraft equipment, turn it off and the ground station generates a TISB for the transponder return so the certified receiver will display the target.

Starting around the October time frame, the ground station software will be modified to generate a TISB for a client that has SDA or SIL of 0. This will make an aircraft using a Skyguard visible to an aircraft using certified equipment as it will receive the TISB. This may show up as ghosting or double targets for non certified receivers such as Stratus, GDL39, Skyradar, etc. After this change the ADS-B Out system such as Skyguard will still be treated as a client and still wake up the ground station, but there will be a TISB target that may appear as a ghost. Software will normally filter this out, but if not, dual targets will be seen.

After the beginning of next year, ADS-B Out systems such as Skyguard will no longer be afforded Client status and will no longer wake up the ground station. Only a TISB target will be generated and only by another aircraft that uses a certified ADS-B Out system.

All of the equipment manufacturers, portable and certified were sent this notice and given a year heads up so they can adapt. They also participated in an industry forum where the FAA developed the intention to resolve what they consider to be a safety issue. NavWorx was included in the communications and I noticed that they sold the manufacturing rights to their portable ADS-B Out system to another company and have dropped it from their website.

One last point, in many cases ADS-B systems are installed but are using an uncertified position source that does not provide the data needed to generate a non zero SIL or SDA value. Such systems or ones that are not configured properly may also set the SDA and SIL to zero, and they will receive the same treatment.
 
Thanks, John.

God, I'm sick of dealing with this crap. Every time I think I've got my installation nailed down, something like this happens. Now, it looks like I am apparently going to have to rewire my panel to use my (ancient, but FAA approved) Garmin GNC-300XL as a position source, instead of my nice, new (but experimental) GRT avionics GPS.

How silly can this get?
 
Jay Honeck said:
Thanks, John.

God, I'm sick of dealing with this crap. Every time I think I've got my installation nailed down, something like this happens. Now, it looks like I am apparently going to have to rewire my panel to use my (ancient, but FAA approved) Garmin GNC-300XL as a position source, instead of my nice, new (but experimental) GRT avionics GPS.

How silly can this get?
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Does the GNC-300XL have WAAS capabilities?
 
So what would happen if someone just "tweaked" their SIL settings? It would be illegal, but would the aircraft have "client" status then?
 
Jay Honeck said:
Thanks, John.

God, I'm sick of dealing with this crap. Every time I think I've got my installation nailed down, something like this happens. Now, it looks like I am apparently going to have to rewire my panel to use my (ancient, but FAA approved) Garmin GNC-300XL as a position source, instead of my nice, new (but experimental) GRT avionics GPS.

How silly can this get?
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Does the GRT GPS have RAIM and WAAS?
 
Jay Honeck said:
Thanks, John.

God, I'm sick of dealing with this crap. Every time I think I've got my installation nailed down, something like this happens. Now, it looks like I am apparently going to have to rewire my panel to use my (ancient, but FAA approved) Garmin GNC-300XL as a position source, instead of my nice, new (but experimental) GRT avionics GPS.

How silly can this get?
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Don't rewire your panel as the GNC-300XL and most non WAAS GPS units can't be used as a compliant position source. I would expect at some point, GRT would add this to their capabilities. It won't have to be certified, but will have to meet the requirements of the TSO's and comply with AC 20-165A.
 
I think it's bizarre that the FAA chooses not to display ADS-B targets because they *might* be (but probably aren't) 50ft from where they are reporting.
 
jsstevens said:
Does the GRT GPS have RAIM and WAAS?
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RAIM and WAAS are not entire issue. There are 19 data items identified in the 91.227 rule. Only one of the items is the latitude and longitude. Many of them are dynamically provided by the position source. Some are configuration and others are based on other inputs to the ADS-B Out system.

AC 20-165A details what is required. The position source may be a non WAAS TSO C129 or TSO C196, but as a practical matter non of the existing GA Non WAAS GPS position sources are available, nor would they be cheaper. Most position sources will be of the WAAS TSO C145/146 variety. The TSO C145 can be a stand alone device and they can be purchased OEM from the new Aspen acquisition Accord Technologies. GRT could purchase this if they don't want to develop their own and integrate it. The retail price should be under $1000.
 
bullwinkle said:
I think it's bizarre that the FAA chooses not to display ADS-B targets because they *might* be (but probably aren't) 50ft from where they are reporting.
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The positions can be bogus and there is no way of knowing if it is accurate or not. They are simply untrustworthy, regardless of their potential accuracy. They maybe within a foot of where they claim to be or more than a mile. I have seen portable systems that are hard coded to claim they have great accuracy and integrity but obviously are not.

Edit: The 95% accuracy requirement is about 300 feet or less. The 99.99999% integrity requirement is 1200 feet or less. These are established for surveillance purposes.
 
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John Collins said:
Starting around the October time frame, the ground station software will be modified to generate a TISB for a client that has SDA or SIL of 0. This will make an aircraft using a Skyguard visible to an aircraft using certified equipment as it will receive the TISB. This may show up as ghosting or double targets for non certified receivers such as Stratus, GDL39, Skyradar, etc. After this change the ADS-B Out system such as Skyguard will still be treated as a client and still wake up the ground station, but there will be a TISB target that may appear as a ghost. Software will normally filter this out, but if not, dual targets will be seen.

After the beginning of next year, ADS-B Out systems such as Skyguard will no longer be afforded Client status and will no longer wake up the ground station. Only a TISB target will be generated and only by another aircraft that uses a certified ADS-B Out system.
.
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So why even bother to allow TISB for a client that has SDA or SIL of 0 when you are going to disable it 3 or 4 months later.
 
John Collins said:
Don't rewire your panel as the GNC-300XL and most non WAAS GPS units can't be used as a compliant position source. I would expect at some point, GRT would add this to their capabilities. It won't have to be certified, but will have to meet the requirements of the TSO's and comply with AC 20-165A.
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Thanks again. I have emailed GRT Avionics to see what their plans are WRT their GPS.
 
dans2992 said:
So what would happen if someone just "tweaked" their SIL settings? It would be illegal, but would the aircraft have "client" status then?
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If a signal that doesn't meet the requirements is modified to meet the requirements, then yes, the requirements will be met, whether it's legal or not.

:dunno:
 
Jim_R said:
If a signal that doesn't meet the requirements is modified to meet the requirements, then yes, the requirements will be met, whether it's legal or not.

:dunno:
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What he's asking about is changing a parameter so the equipment CLAIMS to meet the requirements without actually meeting the requirements. That wouldn't be legal.

John
 
dans2992 said:
So what would happen if someone just "tweaked" their SIL settings? It would be illegal, but would the aircraft have "client" status then?
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There is more to it than that. There are quite a few things that need to be tweaked to make the system appear to be compliant. SIL and SDA can be set by the manufacturer of a portable system, but at this point, they may subject themselves to charges of fraud as it is clear they are doing it knowingly. Other data would have a good chance of giving them away, for example not including the pressure altitude and keeping it the same as what the transponder is transmitting. Not including a geometric altitude or not keeping it close enough to the Baro pressure altitude. Not matching the transponder squawk code. Bad antenna location can result in intermittent broadcasts or poor position results. I looked at reports of one portable unit that only was detected fewer than 20 times on a one hour flight. Could have been a bad unit or a poor antenna location. I have also seen data from other systems that show a fixed value of accuracy well beyond that which is practical on an extended basis. A real position source will not be dramatically better than existing certified systems, so a NIC or NACp that never varies and is well above typical would be suspicious to me. These are dynamic values and routinely change during the flight.

There are some fairly common traits of various position sources and for the most part it is easy to see common errors resulting from using a non compliant one.
 
What is next for the GA world?

So far I can think of in the short period I've been around

#1 Mode A transponders
#2 Mode C transponders
#3 121.50 ELTs
#4 Then mode S transponders became mandatory for a lot of aircraft
#5 They were just finishing up brand new TCAS and EGPWS installations when I was a new mechanic
#6 Then out came WAAS navigators
#7 Then out came 406 ELTs

Now here comes the ADS-B

I'm seeing FANS-1/A+ gear being installed left and right in addition to ADS-B out.

For those who believe things aren't changing, where have you been?
 
bnt83 said:
What is next for the GA world?

So far I can think of in the short period I've been around

#1 Mode A transponders
#2 Mode C transponders
#3 121.50 ELTs
#4 Then mode S transponders became mandatory for a lot of aircraft
#5 They were just finishing up brand new TCAS and EGPWS installations when I was a new mechanic
#6 Then out came WAAS navigators
#7 Then out came 406 ELTs

Now here comes the ADS-B

I'm seeing FANS-1/A+ gear being installed left and right in addition to ADS-B out.

For those who believe things aren't changing, where have you been?
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Perhaps some of them were born yesterday.
 
John Collins said:
There is more to it than that. There are quite a few things that need to be tweaked to make the system appear to be compliant. SIL and SDA can be set by the manufacturer of a portable system, but at this point, they may subject themselves to charges of fraud as it is clear they are doing it knowingly. Other data would have a good chance of giving them away, for example not including the pressure altitude and keeping it the same as what the transponder is transmitting. Not including a geometric altitude or not keeping it close enough to the Baro pressure altitude. Not matching the transponder squawk code. Bad antenna location can result in intermittent broadcasts or poor position results. I looked at reports of one portable unit that only was detected fewer than 20 times on a one hour flight. Could have been a bad unit or a poor antenna location. I have also seen data from other systems that show a fixed value of accuracy well beyond that which is practical on an extended basis. A real position source will not be dramatically better than existing certified systems, so a NIC or NACp that never varies and is well above typical would be suspicious to me. These are dynamic values and routinely change during the flight.



There are some fairly common traits of various position sources and for the most part it is easy to see common errors resulting from using a non compliant one.
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I mention this because our SIL on our GTX330ES was set incorrectly by the shop doing our install (we had all certified gear, so it should be 10E-7, but was 10E-3). We threw all kinds of red flags on the FAA email report, but once we changed the setting back to 10E-7, all was good.
 
dans2992 said:
I mention this because our SIL on our GTX330ES was set incorrectly by the shop doing our install (we had all certified gear, so it should be 10E-7, but was 10E-3). We threw all kinds of red flags on the FAA email report, but once we changed the setting back to 10E-7, all was good.
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This is a common installation error, but although it makes the GTX330ES not compliant, the SIL value should not be zero, so it would not be affected.
 
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