ADS question

AKBill

AKBill

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AKBill
Is ADS using a transponder signal for traffic information?
 
It is still using the signal from your ADS-B "out" equipment to get traffic information. You receive traffic information directly from other aircraft and ground stations. At least thats the way I understand it. Not sure if they are offering transponders with ADS technology but I thought the whole point of ADS was to get rid of transponders and the old radar system.
 
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The way I understand it is in 2020 the FAA will require ADB-B in all aircraft operating in class A, B and C airspace. Will you also required to have mode C transponder or will that system be phased out
 
AKBill said:
The way I understand it is in 2020 the FAA will require ADB-B in all aircraft operating in class A, B and C airspace. Will you also required to have mode C transponder or will that system be phased out
Click to expand...

You have two technology choices for ADS-B, one based on a mode S transponder and the other based on a newer technology UAT. If you go the UAT route, you must still keep your transponder. In addition to the airspace you identified, the rule requires ADS-B out for flying within the 30 NM mode C veil that surrounds the larger class B airports and for flight above 10,000 MSL. The mode C veil is the biggest airspace issue for many aircraft owners.
 
I am using it and I have found myself flying VFR when I would have flown IFR for traffic updates in the past. I was surprised by the number of aircraft funneled into the FDK practice areas and as a result I will also add ADS_B out to my primary training aircraft (a C 172 M) this summer as soon as the RANGR transmitter system is STC'ed (2nd QTR projected.)
 
winrose46 said:
I am using it and I have found myself flying VFR when I would have flown IFR for traffic updates in the past. I was surprised by the number of aircraft funneled into the FDK practice areas and as a result I will also add ADS_B out to my primary training aircraft (a C 172 M) this summer as soon as the RANGR transmitter system is STC'ed (2nd QTR projected.)
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Another question, if I equip my plane with ADS-B can I remove the mode C transponder?
 
AKBill said:
Another question, if I equip my plane with ADS-B can I remove the mode C transponder?
Click to expand...

No. The same airspace that requires ADS-B also requires a transponder with mode C or S. A mode S transponder with ES is both a transponder and a ADS-B Out system. If you go the UAT route, you must keep the transponder.
 
AKBill said:
Another question, if I equip my plane with ADS-B can I remove the mode C transponder?
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Still need it. It will be awhile before they completely phase out radar
 
Gucci Pilot said:
Still need it. It will be awhile before they completely phase out radar
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FAA has no plan to phase out radar, at least according to the final ADS-B rule. It also would require a major update to existing TCAS systems in all the aircraft mandated to use them. This is not going to happen in my lifetime.
 
John Collins said:
FAA has no plan to phase out radar, at least according to the final ADS-B rule. It also would require a major update to existing TCAS systems in all the aircraft mandated to use them. This is not going to happen in my lifetime.
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I suppose it's a 'government program/not required to be logical' thing but...if ADS-B isn't destined to replace radar that's destined to be phased out then why the focus on getting ADS-B operational in places where radar coverage is good while those vast areas where radar coverage is poor to nonexistant at the lower altitudes will likely be the last to see ADS-B operational?
 
peerlesscowboy said:
I suppose it's a 'government program/not required to be logical' thing but...if ADS-B isn't destined to replace radar that's destined to be phased out then why the focus on getting ADS-B operational in places where radar coverage is good while those vast areas where radar coverage is poor to nonexistant at the lower altitudes will likely be the last to see ADS-B operational?
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From what I can see, ADS-B is mostly for the airlines and to improve the flow at the major hubs. Although it will have high reliability, there will be GPS outages and equipment outages from time to time. Radar will still be needed as the backup system. The FAA final rule indicated that the least cost option would have been to keep the existing radar system, but that it would have difficulty in supporting the future traffic growth anticipated. They said they would keep radar as the backup. As part of that, all the primary radars would be maintained. The secondary radars would be kept for the terminal areas and to cover airspace above FL180. The older secondary radars would be phased out, but the additional expense of maintaining the ADS-B infrastructure would still go up. The benefits of the system were mainly accrued by the airlines, although now that is being questioned because overall system wide, users and government, the benefits do not exceed the costs.

So far, all the nextgen benefits and changes seem to be independent of ADS-B. Other than the FISB and traffic services, GA does not benefit much at all.
One of the areas where ADSB does benefit GA is surveillance over the Gulf of Mexico. The other major benefit to GA is already in place and independent of ADSB, LPV approaches. I see very little benefit to GA for ADS-B and in particular great potential harm for airports and aircraft that operate in, into, and out of airports inside the mode C veil. That is why I submitted a petition to the FAA on this topic to eliminate the mode C veil requirement for ADSB.

Full disclosure, I drank the cool aid and installed a GDL88.
 
John Collins said:
..................................................................

Full disclosure, I drank the cool aid and installed a GDL88.
Click to expand...
Thank you for all the info.
I plan to install a GDL88 myself, was planning for this year but I happened to stumble on a deal I couldn't refuse on a good used GNS430W quite by accident, having it installed as we speak. Budget update is for the GDL88 installation next year, I anticipate ADS-B should give me quasi-radar service out across the vast middle of Montana where real radar coverage is poor to non-exsistant below 14,000'. At the rate the government is getting ADS-B up and running I'd guess even then I'll have the capability before the gov't picks up it's end of the bargin?
 
peerlesscowboy said:
At the rate the government is getting ADS-B up and running I'd guess even then I'll have the capability before the gov't picks up it's end of the bargin?
Click to expand...

ADS-B tower build-out is more-or-less complete in the lower 48. Integration of the data is a lot less than complete. When I talked to Denver Approach about it last fall they just laughed and said they had no access to ADS-B data. I do get traffic & weather data as promised so that part of the system works. I haven't flown over MT so don't know how things are up there. It works fine over WY with traffic and weather data.
 
John Collins said:
No. The same airspace that requires ADS-B also requires a transponder with mode C or S. A mode S transponder with ES is both a transponder and a ADS-B Out system. If you go the UAT route, you must keep the transponder.
Click to expand...

Ok another question or two. I live in Alaska, no class C for many miles, my NARCO 50A transponder is not working and my NARCO MK12DR is having transmitting issues.

What is a good mode C transponder to replace the NARCO with and should I replace the NARCO 12DR NAV/COM radio with just a COM radio. I do not fly IFR and have an AREA 500 Garmin GPS, King KX170B NAV/COM as second radio.

I am thinking strongly on getting the ADS-B Out system as traffic here in the summer gets very busy.
 
John Collins said:
From what I can see, ADS-B is mostly for the airlines and to improve the flow at the major hubs. Although it will have high reliability, there will be GPS outages and equipment outages from time to time. Radar will still be needed as the backup system. The FAA final rule indicated that the least cost option would have been to keep the existing radar system, but that it would have difficulty in supporting the future traffic growth anticipated. They said they would keep radar as the backup. As part of that, all the primary radars would be maintained. The secondary radars would be kept for the terminal areas and to cover airspace above FL180. The older secondary radars would be phased out, but the additional expense of maintaining the ADS-B infrastructure would still go up. The benefits of the system were mainly accrued by the airlines, although now that is being questioned because overall system wide, users and government, the benefits do not exceed the costs.

So far, all the nextgen benefits and changes seem to be independent of ADS-B. Other than the FISB and traffic services, GA does not benefit much at all.
One of the areas where ADSB does benefit GA is surveillance over the Gulf of Mexico. The other major benefit to GA is already in place and independent of ADSB, LPV approaches. I see very little benefit to GA for ADS-B and in particular great potential harm for airports and aircraft that operate in, into, and out of airports inside the mode C veil. That is why I submitted a petition to the FAA on this topic to eliminate the mode C veil requirement for ADSB.

Full disclosure, I drank the cool aid and installed a GDL88.
Click to expand...

Thanks for the information, looing strongly at ADS-B. Also looking for reliable used Mode C transponder to replace my NARCO 50A that went tits up
 
John Collins said:
From what I can see, ADS-B is mostly for the airlines and to improve the flow at the major hubs. Although it will have high reliability, there will be GPS outages and equipment outages from time to time. Radar will still be needed as the backup system. The FAA final rule indicated that the least cost option would have been to keep the existing radar system, but that it would have difficulty in supporting the future traffic growth anticipated. They said they would keep radar as the backup. As part of that, all the primary radars would be maintained. The secondary radars would be kept for the terminal areas and to cover airspace above FL180. The older secondary radars would be phased out, but the additional expense of maintaining the ADS-B infrastructure would still go up. The benefits of the system were mainly accrued by the airlines, although now that is being questioned because overall system wide, users and government, the benefits do not exceed the costs.

So far, all the nextgen benefits and changes seem to be independent of ADS-B. Other than the FISB and traffic services, GA does not benefit much at all.
One of the areas where ADSB does benefit GA is surveillance over the Gulf of Mexico. The other major benefit to GA is already in place and independent of ADSB, LPV approaches. I see very little benefit to GA for ADS-B and in particular great potential harm for airports and aircraft that operate in, into, and out of airports inside the mode C veil. That is why I submitted a petition to the FAA on this topic to eliminate the mode C veil requirement for ADSB.

Full disclosure, I drank the cool aid and installed a GDL88.
Click to expand...

I also believe that ARTCC separation can now be reduced from 5 miles to 3 miles. Today, any targets over 40 (?) miles from a radar site must use 5 miles, and last I heard the implementation of ADS-B will reduce it back down to the 3 mile norm.
 
AKBill said:
Ok another question or two. I live in Alaska, no class C for many miles, my NARCO 50A transponder is not working and my NARCO MK12DR is having transmitting issues.

What is a good mode C transponder to replace the NARCO with and should I replace the NARCO 12DR NAV/COM radio with just a COM radio. I do not fly IFR and have an AREA 500 Garmin GPS, King KX170B NAV/COM as second radio.

I am thinking strongly on getting the ADS-B Out system as traffic here in the summer gets very busy.
Click to expand...

if your transponder is bad and needs to be replaced, you might as well go with a mode S transonder. I went with the KT74. Although you may not need it for ADSB compliance, it's one less piece you will need later.
 
Clark1961 said:
ADS-B tower build-out is more-or-less complete in the lower 48. Integration of the data is a lot less than complete. When I talked to Denver Approach about it last fall they just laughed and said they had no access to ADS-B data. I do get traffic & weather data as promised so that part of the system works. I haven't flown over MT so don't know how things are up there. It works fine over WY with traffic and weather data.
Click to expand...

We have a opposite problem here in Arkansas. ATC can see our ADSB but the tower coverage towards the southwest corner is lacking. They really need one additional tower.

Little Rock APP/DEP was happy to test our ADSB out.
 
rbridges said:
if your transponder is bad and needs to be replaced, you might as well go with a mode S transonder. I went with the KT74. Although you may not need it for ADSB compliance, it's one less piece you will need later.
Click to expand...
Do you think mode S will eventually be mandated?
I'm planning to go with a GDL88 which along with my KT76A mode C transponder and soon to be installed GNS430W should I assume put me in compliance with the 2020 mandate.
 
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John Collins said:
From what I can see, ADS-B is mostly for the airlines and to improve the flow at the major hubs. Although it will have high reliability, there will be GPS outages and equipment outages from time to time. Radar will still be needed as the backup system. The FAA final rule indicated that the least cost option would have been to keep the existing radar system, but that it would have difficulty in supporting the future traffic growth anticipated. They said they would keep radar as the backup. As part of that, all the primary radars would be maintained. The secondary radars would be kept for the terminal areas and to cover airspace above FL180. The older secondary radars would be phased out, but the additional expense of maintaining the ADS-B infrastructure would still go up. The benefits of the system were mainly accrued by the airlines, although now that is being questioned because overall system wide, users and government, the benefits do not exceed the costs.

So far, all the nextgen benefits and changes seem to be independent of ADS-B. Other than the FISB and traffic services, GA does not benefit much at all.
One of the areas where ADSB does benefit GA is surveillance over the Gulf of Mexico. The other major benefit to GA is already in place and independent of ADSB, LPV approaches. I see very little benefit to GA for ADS-B and in particular great potential harm for airports and aircraft that operate in, into, and out of airports inside the mode C veil. That is why I submitted a petition to the FAA on this topic to eliminate the mode C veil requirement for ADSB.

Full disclosure, I drank the cool aid and installed a GDL88.
Click to expand...

That's how I see it as well. Only thing I'm skeptical about is the claim of the refresh rate reducing separation standards. That can be applied in some cases but a lot of times the separation is for wake turbulence and has nothing to do with refresh rate. Not sure it'll be all that beneficial in that respect. Now oceanic routes, I see a huge benefit.

Another thing I'm curious about is the claim on savings by shutting down existing radars. If they shut them down, then how will the VFR (non 1090 ES) guys get FF outside of the required ADS-B airspace? If primary and secondary radar is still going to be maintained as a back up, they're still gonna have to do regular checks and maintenance to ensure it's ready to go at a moment's notice. That's gonna cost a chunk of money. I think there's still a lot of procedural questions that haven't been completely worked out for the 2020 implementation.
 
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peerlesscowboy said:
Do you think mode S will eventually be mandated?
I'm planning to go with a GDL88 which along with my KT76A mode C transponder and soon to be installed GNS430W should I assume put me in compliance with the 2020 mandate.
Click to expand...

I doubt it. I know there are workarounds available to let you keep your old transponder, but if you have to replace it anyway, it just makes sense to get a newer one IMO.
 
rbridges said:
I doubt it. I know there are workarounds available to let you keep your old transponder, but if you have to replace it anyway, it just makes sense to get a newer one IMO.
Click to expand...
My understanding is that mode S doesn't have an anonymous mode which may or may not be important to you, it is to me as it may or may not be to AKBill? Just wanted to make sure he understands that with the KT74 mode S transponder he'll be broadcasting his N number anytime the transponder is on.
 
peerlesscowboy said:
Thank you for all the info.
I plan to install a GDL88 myself, was planning for this year but I happened to stumble on a deal I couldn't refuse on a good used GNS430W quite by accident, having it installed as we speak. Budget update is for the GDL88 installation next year, I anticipate ADS-B should give me quasi-radar service out across the vast middle of Montana where real radar coverage is poor to non-exsistant below 14,000'. At the rate the government is getting ADS-B up and running I'd guess even then I'll have the capability before the gov't picks up it's end of the bargin?
Click to expand...

If you don't mind me asking, what's the going rate for a GDL-88 install now, anyways? I already have a GNS430W, so I just need to start budgeting for the GDL-88 and installation.
 
peerlesscowboy said:
My understanding is that mode S doesn't have an anonymous mode which may or may not be important to you, it is to me as it may or may not be to AKBill? Just wanted to make sure he understands that with the KT74 mode S transponder he'll be broadcasting his N number anytime the transponder is on.
Click to expand...

good point. Personally, I don't mind my N# being broadcast, but I know many people don't like it.
 
rbridges said:
I doubt it. I know there are workarounds available to let you keep your old transponder, but if you have to replace it anyway, it just makes sense to get a newer one IMO.
Click to expand...

Garmin and others sell some pretty reliable solid state mode A/C transponders. They are still less expensive than mode S.
 
AKBill said:
Ok another question or two. I live in Alaska, no class C for many miles, my NARCO 50A transponder is not working and my NARCO MK12DR is having transmitting issues.

What is a good mode C transponder to replace the NARCO with and should I replace the NARCO 12DR NAV/COM radio with just a COM radio. I do not fly IFR and have an AREA 500 Garmin GPS, King KX170B NAV/COM as second radio.

I am thinking strongly on getting the ADS-B Out system as traffic here in the summer gets very busy.
Click to expand...

If you want to be ADS-B compliant, I believe if you put in the GTX-330 ES with a WAAS box feeding (the Garmin 400 is likely the cheapest solution and allows the Flight Stream link) you will be fully covered for requirements. That doesn't get you anything in though, but it gives you access to all the global airspace.
 
mkosmo said:
If you don't mind me asking, what's the going rate for a GDL-88 install now, anyways? I already have a GNS430W, so I just need to start budgeting for the GDL-88 and installation.
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I had a quote around here someplace, can't seem to find it now :redface: Seems like it was something like four to five thousand installed as I recall. Maybe somebody that's got a more organized office than I do could chime in? In the meantime it's prob'ly about time I cleaned this mess up anyway :dunno:
 
peerlesscowboy said:
My understanding is that mode S doesn't have an anonymous mode which may or may not be important to you, it is to me as it may or may not be to AKBill? Just wanted to make sure he understands that with the KT74 mode S transponder he'll be broadcasting his N number anytime the transponder is on.
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Thanks, makes no mind to me, N number broadcasting. Unless I fly to Anchorage 800 miles, Seattle 900 miles, or White Horse Yukon Canada 250 miles no transponder needed.
 
Henning said:
If you want to be ADS-B compliant, I believe if you put in the GTX-330 ES with a WAAS box feeding (the Garmin 400 is likely the cheapest solution and allows the Flight Stream link) you will be fully covered for requirements. That doesn't get you anything in though, but it gives you access to all the global airspace.
Click to expand...

So exactly what global airspace are you denied access to by not having ES other than IFR in Australia?
 
peerlesscowboy said:
I had a quote around here someplace, can't seem to find it now :redface: Seems like it was something like four to five thousand installed as I recall. Maybe somebody that's got a more organized office than I do could chime in? In the meantime it's prob'ly about time I cleaned this mess up anyway :dunno:
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That's better than I was expecting, actually. Now just to accrue the funds and find an avionics shop that can fit me in their schedule. Or I'll just wait until New Years Eve 2019 :)
 
Recently did the exact update mentioned before. Updated the Garmin 330 to 330 ES (already had WAAS box). We are now compliant. Was cheapest alternative for us. The amount of traffic seen on the Stratus 2 is very good (though not totally complete.) Flew through Miami and all the planes shown was mind blowing. Might have been better to keep my head in the sand and not know.
You can turn off the ADS-B out through some PITA menus on the 330ES, but don't have any plans on buzzing over any politicians anytime soon, so will leave it on.
 
Code90 said:
You can turn off the ADS-B out through some PITA menus on the 330ES, but don't have any plans on buzzing over any politicians anytime soon, so will leave it on.
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You can't turn ADS-B off other than by turning the transponder off. Your GTX330 has been transmitting your N number since it was installed, long before you upgraded to ES. All mode S transponders always transmit the aircraft ID information, regardless if they are ADS-B or not.
 
Code90 said:
Recently did the exact update mentioned before. Updated the Garmin 330 to 330 ES (already had WAAS box). We are now compliant. Was cheapest alternative for us. The amount of traffic seen on the Stratus 2 is very good (though not totally complete.) Flew through Miami and all the planes shown was mind blowing. Might have been better to keep my head in the sand and not know.
You can turn off the ADS-B out through some PITA menus on the 330ES, but don't have any plans on buzzing over any politicians anytime soon, so will leave it on.
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Roger on politicians, Thanks
 
Anchorage ops doesn't require a transponder. A good example is Lake Hood. It sits within the Anchorage International Airport complex and shares the same control tower and depending on seasonal traffic load, the same controllers. When I fly north from Hood there's a small sliver of airspace that allows me to go with no transponder. Not as an exception, but as a rule. I typically fly adjacent (about 1/2 mile) to 747s and other commercial airline traffic from ANC, over crossing Merrill Field traffic, and under crossing Elmendorf military jet traffic. Typical vertical separation from crossing traffic is about 300'. No transponder is required. More to the topic at hand, Alaska is exempt from the 2020 ADS-B mandate and knowing pilots? If it isn't required, they won't spend any money to add it.
 
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That blanket statement isn't technically correct for small GA but in the practical sense it is correct. From the FAA-
Under the rule, ADS-B Out performance will be required to operate in:
Class A, B, and C.
Class E airspace within the 48 contiguous states and the District of Columbia at and above 10,000 feet MSL, excluding the airspace at and below 2,500 feet above the surface.
Class E airspace at and above 3,000 feet MSL over the Gulf of Mexico from the coastline of the United States out to 12 nautical miles.
Around those airports identified in 14 CFR part 91, Appendix D.
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From what I can tell ADS-B is also required ABOVE any A,B or C airspace up to 10K.
So if you're not equipped you can not even fly over a class C airport...it effectively makes C go from whatever the floor is to 10,000 feet.
Right now SHV class C tops at 4300' msl. After 2020 it will top out at 10K no?
What a bunch of useless crap...:mad2:

Chris
 
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Hiperbiper said:
From what I can tell ADS-B is also required ABOVE any A,B or C airspace up to 10K.
So if you're not equipped you can not even fly over a class C airport...it effectively makes C go from whatever the floor is to 10,000 feet.
Right now SHV class C tops at 4300' msl. After 2020 it will top out at 10K no?
What a bunch of useless crap...:mad2:

Chris
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Except for Class A airspace, you are correct. However, this is no different than the transponder requirement. If you don't have a transponder with altitude reporting capability today, you may not fly above the B or C or 30 NM Mode C veil. In 2020, you will also need ADS-B Out.
 
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