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ADSB Anonymous Mode?

Bud K

Well Known Member
I am installing a GDL 82 in my RV-7. I've read some older posts regarding this topic but haven't found any recent updates.

I am wondering if I should wire a switch for 'Anonymous Mode'. I understand that the only thing that Anonymous Mode does for you is that your N number is not displayed if your below 18,000' and squawking 1200. I also understand the FARs in that if your aircraft is ADSB out equipped, it must be operational whenever the aircraft is operating/in motion (meaning no 'off' or 'standby' modes).

Wouldn't you meet the FARs regarding ADSB operation in Anonymous Mode? What about flying over Class B airspace. Technically, your ADSB Out is still operating but your N number is not being displayed.
 
There's no switch. It's a config setting. With it ON you will broadcast a phony id when you squawk 1200. Any other squawk will send your real tail number. The GDL82 is 978mhz and not legal above 18,000'.
 
There's no switch. It's a config setting. With it ON you will broadcast a phony id when you squawk 1200. Any other squawk will send your real tail number. The GDL82 is 978mhz and not legal above 18,000'.
This is NOT correct. There is a switch that must be installed on the GDL82. If one wishes to operate it in anonymous mode, you would have to engage that mode using that switch. Also, it is not broadcasting a 'phony' ID. An ADS-B display will show "VFR" in place of your N number.

The original poster's comments are correct. One note though concerning your comment about keeping the ADS-B on. What you stated is correct, but don't be confused thinking the anonymous mode 'turns off' the ADS-B. It does not. It only prevents the unit from broadcasting your N number when activated by the switch.
 
Yes there is

A switch. You can wire a switch that let's you go anonymous or squawk your n number.
You can only be anonymous when squawking 1200. Any other code it will transmit your n number. The anonymous mode will squawk a random code I'm sure the faa will find you if they want.
You DON'T need to wire the switch it's optional.
 
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Does it also stop sending out your unique serial number so ATC can't track you if you are squawking 1200?

Oh wait, mode-S does that anyway.

**** the FAA for tacking all of us.

BTW, commercial boaters are now required to install something similar and they are not pleased about it.
 
Does it also stop sending out your unique serial number so ATC can't track you if you are squawking 1200?

Oh wait, mode-S does that anyway.

**** the FAA for tacking all of us.

BTW, commercial boaters are now required to install something similar and they are not pleased about it.

Hey Bill, think of the FAA as your wife. If your doing something you wouldn?t want them to know about.....you probably shouldn?t be doing it.😇
 
Mode S, 1090ES = Self Lojacked.

Mode C only, UAT 978 Out only, optional lojacking. My GRT EFIS shows a constant traffic alert of me to me as a VFR1200 code if I chose Anonymous. Toggle the Skybeacon Anonymous off, GRT recognizes and suppresses myself.

Avare acts similarly.
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15500135996480.jpg
 
Hey Bill, think of the FAA as your wife. If your doing something you wouldn?t want them to know about.....you probably shouldn?t be doing it.😇

I hope you will find people digging in to your finances, purchasing habits, and location with such acceptance.

Your comment has already been registered in your dossier to associate your views with others like you, and has been sold to many agencies for their targeted influence campaigns.
 
Anonymous mode for 1090ES

Check out the feb 2019 issue of AOPA Magazine. There?s a nice article about The efforts to implement an anonymous mode for 1090ES. They are talking about a ?rolling? ICAO code. Not at all sure how that would be implemented. Sounds like they have some level of buy-in from the FAA so this may actually happen. Any thoughts from the xponder manufacturers that monitor VAF?
This complicates my decision on upgrading....
 
If you depart with a code, like from a Class C, then switch to anonymous mode when ATC tells you to squawk VFR, "the system" continues to track your flight under your N-number. Doing it the other way around, "the system" only shows your track beginning at the point when you were given a squawk code. At least, that's been my experience with my GDL-82. It's my belief that if you want to remain anonymous, you must depart and land squawking 1200 in anonymous mode. Personally, I don't see the point.
 
Hi Steve, thanks for the fast response. I’m talking about anonymous mode for 1090ES. I was curious about the possible impact to the equipment to implement said mode. Maybe an easy entry screen in conjunction with a secure ID fob? Although that would make me anonymous to “airplane spotters” but not the govt?
Again this is something new and not here yet but the FAA has an acronym for it so that’s at least something ;)
“Private ICAO Addresses” PIA. There is supposed to be a technology demonstration in early 2019.
 
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Hey Bill, think of the FAA as your wife. If your doing something you wouldn?t want them to know about.....you probably shouldn?t be doing it.😇
That's kind of like saying, why not let the authorities search your home or track you in your car, if you haven't done something wrong.

A government that tracks it citizens doesn't trust it citizens.
 
That's kind of like saying, why not let the authorities search your home or track you in your car, if you haven't done something wrong.

A government that tracks it citizens doesn't trust it citizens.

The next step will be fees of all sorts. Our ADS-B will be used like an EZ Toll.
 
No point to it

It's my belief that if you want to remain anonymous, you must depart and land squawking 1200 in anonymous mode. Personally, I don't see the point.

That?s my understanding too. 90% of my flying will be where Mode C is not required anyway.

The FAA?s NexGen website (in the FAQs) states that anonymous mode ?enables the transceiver to broadcast a randomized flight ID and a pseudo-ICAO address?. Sounds strange to me.
 
I installed the switch even though I leave it in anonymous mode almost all the time. In order to qualify for the rebate I had to do the verification flight with anonymous mode off, otherwise I might have just run pin 5 to ground and been in anonymous mode all the time.

I verified with Carl in his new, to him, RV-8 that when flipping the switch on I show up as "VFR" and with the switch off I show up with my tail number. ATC can still see the tail number, the only thing I am trying to avoid is all of the tracking web sites who have no need or right to know where I am at any given point.
 
That's kind of like saying, why not let the authorities search your home or track you in your car, if you haven't done something wrong.

A government that tracks it citizens doesn't trust it citizens.

You would be shocked at what activity the Govt is tracking and has at their fingertips. A few years after 9/11 I showed up at ORD and had left my wallet at home with my drivers license in it. A nice TSA lady pulled me aside and offered to help, as I had a very important meeting that afternoon. She said they could get me through. She put me on the phone with some Govt person who asked me a lot of questions to verify my identity. I was literally SHOCKED with the level and type of information they not only knew about me, but were able to pull up on a single computer screen in 10 seconds. The patriot act was the single largest reduction in privacy rights we have ever seen in this country. Our founding fathers must have been rolling in their graves.

Larry
 
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Paranoid

This makes as much sense as people that cover a car license plate they?re selling, meanwhile thousands of people and license plate readers see them all day.
Who cares where you go unless you?re cheating on your wife.
My dad had a case like that when a guy had a hard landing in Alaska the troopers tracked him down and when a concerned citizen was called at the guys house they said he and his wife were ok. Too bad the woman that picked up the phone at the guys home was his wife.
Believe me no one on this thread is important enough for anyone to care about. The black helicopters are not coming for you.
 
Anyway, you do something stupid enough to get their attention going anonymous isn?t going to prevent them from finding you.
 
This is NOT correct. There is a switch that must be installed on the GDL82. If one wishes to operate it in anonymous mode, you would have to engage that mode using that switch. Also, it is not broadcasting a 'phony' ID. An ADS-B display will show "VFR" in place of your N number.

In anonymous mode the unit replaces your unique ICAO identifier with a random number generated onboard so it is in fact a phony number and statistically impossible to match an actual other aircraft. So while not spoofing it is phony.
 
Mode S, 1090ES = Self Lojacked.

Mode C only, UAT 978 Out only, optional lojacking. My GRT EFIS shows a constant traffic alert of me to me as a VFR1200 code if I chose Anonymous. Toggle the Skybeacon Anonymous off, GRT recognizes and suppresses myself.

Avare acts similarly.
15500136296461.jpg


15500135996480.jpg

That is an issue with your "in" equipment. Most in units do a very good job of filtering ghosting whether operating in ananymous mode or not. Contact your in manufacturer to check for software updates.
 
If you depart with a code, like from a Class C, then switch to anonymous mode when ATC tells you to squawk VFR, "the system" continues to track your flight under your N-number. Doing it the other way around, "the system" only shows your track beginning at the point when you were given a squawk code. At least, that's been my experience with my GDL-82. It's my belief that if you want to remain anonymous, you must depart and land squawking 1200 in anonymous mode. Personally, I don't see the point.

As of now the system does not continue to track you if you transition from discrete code ATC services to VFR in anonymous mode. So at that point forward the flight is equivalent to an anonymous flight without ATC interaction.
 
I installed the switch even though I leave it in anonymous mode almost all the time. In order to qualify for the rebate I had to do the verification flight with anonymous mode off, otherwise I might have just run pin 5 to ground and been in anonymous mode all the time.

I verified with Carl in his new, to him, RV-8 that when flipping the switch on I show up as "VFR" and with the switch off I show up with my tail number. ATC can still see the tail number, the only thing I am trying to avoid is all of the tracking web sites who have no need or right to know where I am at any given point.

FAA regulations require anonymous mode be switched, either with a hardwired mechanical switch or a menu/app selection. So hardwiring pin 5 violates the regs.

And your understanding of the anonymous mode N number information is incorrect. If you are in anonymous mode then even ATC doesn't have access to your N number. That is not possible from both a physical (random ICAO) and by regulatory specifications for Mode C systems.
 
The black helicopters are not coming for you.

I doubt the average VAF reader is concerned about black helicopters.

These are sport aircraft. Ever do a nice smooth roll in cruise, just for the sheer joy of it? Maybe break into a mock dogfight? Did you check your proximity to an airway?

Ever nipped the edge of some airspace? Bumped the bottom of a Class B overhang? Maybe flew by your buddy's boat on the lake, and got a little low?

Some here may be Immaculate, but bless me Father, for I have sinned...

And yes, I suspect the future includes tolls. Time will tell, but ADSB certainly puts a chunk of the infrastructure into place.
 
This makes as much sense as people that cover a car license plate they’re selling, meanwhile thousands of people and license plate readers see them all day.
Who cares where you go unless you’re cheating on your wife.
My dad had a case like that when a guy had a hard landing in Alaska the troopers tracked him down and when a concerned citizen was called at the guys house they said he and his wife were ok. Too bad the woman that picked up the phone at the guys home was his wife.
Believe me no one on this thread is important enough for anyone to care about. The black helicopters are not coming for you.

First, because we live in America where privacy and our right to travel freely without interference is fundamental. What if your state passed a law to display the name and address of motor vehicle owners on the side of every vehicle for all to see? Second, the FAA has computer systems to track and monitor aircraft that automatically log violations (ever innocently clip a corner of a stadium TFR or Class D ring?). Third it is akin to a taxi meter in place and ready to go for user fees and those same computers are waiting in the wings. It has nothing to do with trying to get away with illegal activity. By the way, those same nanny computers in the system is why the Oshkosh arrival NOTAM states that all Mode C only aircraft squawk "standby" while all ADS-B equipped aircraft remain on ALT. Even though the targets drive ATC nuts the "red light" computers in OKC would be spitting out violation notices faster than they could keep the printers loaded with paper. This is also why airshow performers who are equipped cannot fly the airshow without their equipment on and operable. Even in waivered airspace! This was explained during the Oshkosh performers briefing last year to the pilots. The FAA admitted there are still a lot of snags with ADS-B. Sometimes when flying formation ATC will request wing men sqwawk standby. If the wingman has ADS-B out technically ATC should not make the request and the pilot should not do it. The regs say that unless the pilot has declared an emergency ATC cannot request you violate a regulation or give such permission. More ridiculousness. Personally I opt to switch to standby to help them out and figure I can lean on their request should a violation notice arrive. Mandate rules and deep state nanny computers be damned. :)
 
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Flightaware does - or did six months ago. I'm not sure about the FAA "system".

As a Flightaware flight feeder provider with a premium account, I can assure you it does not if you have Mode C an you are squawking 1200 in anonymous mode. In fact Flightaware doesn't even specifically track the 978 mhz UAT frequency so most of the time even when not in anonymous mode you won't show up. I have had discussions with them about that. But their whole system is based exclusively on 1090ES. The only reason you even show up at all on their system is 1) you are not in anonymous, 2.) you are sqwawking a discrete assigned code and 3.) the rebroadcasting of your information triggered by ATC and/or other aircraft equipped with 1090mhz out. So your UAT out equipment right out of the box doesn't play well with most private tracking systems like Flightaware. Which I see as another plus. ;)
 
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Anyway, you do something stupid enough to get their attention going anonymous isn’t going to prevent them from finding you.
FWIW: Having spent 22yrs in Federal Law Enforcement I can say this is completely true. Even with absolutely no electrical system in your aircraft there is no place on Earth you can go if they really wanted to track your aircraft. Thankfully they don't have the time or resources to care about you or what you are doing. People think they are more important than what they really are, but to each his own.

:cool:
 
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ADSB Anonymous mode

Garmin guys please pipe in here.

Now that I have installed a GDL-82 I am confused about the anonymity mode. I couldn’t find any info in the installation manual that says the switch is optional nor could I find info that says the switch is actually required to have anonymous mode available, it says, “if switch is installed” which leads me to believe it is optional but if the switch IS NOT installed is the anonymous mode still available? In the configuration section of the manual it describes setting up the GDL-82 after installation

Can’t the wiring and/or the configuration be set up so that any time 1200 is selected it automatically goes into anonymous mode without any switch?

2.1.1 Anonymous Mode
In anonymous mode, the GDL 82 transmits a temporary address instead of the aircraft’s assigned ICAO address code, and a temporary Flight ID.

Anonymous Mode*
The Anonymous Mode* discrete input supports activation of the anonymous mode feature. When the discrete is grounded and the integrated transponder is tuned to the configured VFR squawk code, the GDL 82 will enter anonymous mode. If the integrated transponder is not tuned to the VFR squawk code, the GDL 82 will not enter anonymous mode in either discrete state.

7.3.4 ADS-B Selections
Anonymous Mode Switch
Select if an Anonymous Mode switch is installed. This setting controls the availability of the UAT anonymity feature. Consult the aircraft operator for guidance on whether this feature should be installed. When installed, enabled, and the flight crew selects the anonymous mode with the transponder tuned to the VFR code, the GDL 82 transmits a temporary address instead of the aircraft’s assigned ICAO address code, and a temporary Flight ID.
 
As of now the system does not continue to track you if you transition from discrete code ATC services to VFR in anonymous mode. So at that point forward the flight is equivalent to an anonymous flight without ATC interaction.
They may not see you live on the screen as you're flying, but if you take off from somewhere on a discrete code, then go anonymous as you leave the zone, the records will still show that this discrete code left the zone at this Lat/Long at this time, altitude, speed, and heading. And oh, look, this anonymous code showed up at the exact same place and time doing the exact same thing. Let's see where it went! And with a high probability that might convince a judge, they'll know it's you.
 
Garmin guys please pipe in here.

Now that I have installed a GDL-82 I am confused about the anonymity mode. I couldn?t find any info in the installation manual that says the switch is optional nor could I find info that says the switch is actually required to have anonymous mode available....

Not a Garmin guy, but the question is easy enough. Ground Pin 5 and you'll always be in anonymous mode when squawking 1200. Or put a switch between Pin 5 and ground; with the switch open, you will NOT be anonymous.
 
Garmin guys please pipe in here.

Now that I have installed a GDL-82 I am confused about the anonymity mode. I couldn?t find any info in the installation manual that says the switch is optional nor could I find info that says the switch is actually required to have anonymous mode available, it says, ?if switch is installed? which leads me to believe it is optional but if the switch IS NOT installed is the anonymous mode still available? In the configuration section of the manual it describes setting up the GDL-82 after installation

Can?t the wiring and/or the configuration be set up so that any time 1200 is selected it automatically goes into anonymous mode without any switch?

The GDL 82 will enter anonymous mode only when the switch (discrete input into the GDL 82) is active. The switch is optional. If not installed, the unit will not operate in anonymous mode. Per the installation manual, when the switch is active and the squawk code is 1200, it will be in anonymous mode. Hopefully this information is helpful in operating your aircraft. If you have more questions, you may wish to contact us directly.

Thanks,
Levi
 
Levi,

How about what Dan Horton said above?

“Not a Garmin guy, but the question is easy enough. Ground Pin 5 and you'll always be in anonymous mode when squawking 1200. Or put a switch between Pin 5 and ground; with the switch open, you will NOT be anonymous.”

If I ground pin 5 during installation isn’t this the same as having the switch active? Then I don’t need to install a switch.
 
FAA regulations require anonymous mode be switched, either with a hardwired mechanical switch or a menu/app selection. So hardwiring pin 5 violates the regs.

And your understanding of the anonymous mode N number information is incorrect. If you are in anonymous mode then even ATC doesn't have access to your N number. That is not possible from both a physical (random ICAO) and by regulatory specifications for Mode C systems.

Levi,

How about what Dan Horton said above?

?Not a Garmin guy, but the question is easy enough. Ground Pin 5 and you'll always be in anonymous mode when squawking 1200. Or put a switch between Pin 5 and ground; with the switch open, you will NOT be anonymous.?

If I ground pin 5 during installation isn?t this the same as having the switch active? Then I don?t need to install a switch.
Yep, that is what would happen. However, there is that minor legality issue pointed out above in the regulations.
 
FAA regulations require anonymous mode be switched, either with a hardwired mechanical switch or a menu/app selection. So hardwiring pin 5 violates the regs.

Reference please.

UPDATE

Got an email from a buddy who, due to a prior position, is very familiar with the ADS-B program. He suggests the reference in play here may be AC 20-165B, dated 12-07-15, specifically paragraph 3.7.2.3.4:

3.7.2.3.4 The ADS-B equipment may only allow selection of the anonymous
24-bit address via a dedicated pilot interface. The ADS-B OUT equipment
may not automatically set an anonymous 24-bit address or set a blank
(Not Available per RTCA/DO-282()) call sign based solely on pilot
selection of the 1200 Mode 3/A code.


Two prior paragraphs are also relevant:

3.7.2.3.1 When the ADS-B equipment is initially powered-on, the 24-bit
address must default to the aircraft’s assigned ICAO 24-bit address.

3.7.2.3.2 When the ADS-B equipment is initially powered-on, the call
sign may not be blank (Not Available per RTCA/DO-282()). At initial
power-on, it is acceptable for the call sign to revert to a non-blank
call sign that existed before the ADS-B equipment being powered off, or
to the aircraft registration number.


Although the above seems quite firm, please note the document is an advisory circular. Like it says on the first page, "This AC is not mandatory and does not constitute a regulation."

Anyone know of a regulation?
 
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Dated and only an AC, but quoted:
AC No: 20-165B
Subject: Airworthiness Approval of Automatic
Dependent Surveillance - Broadcast OUT Systems
Date: 12/07/15

3.7.2.3.4 The ADS-B equipment may only allow selection of the anonymous 24-bit
address via a dedicated pilot interface. The ADS-B OUT equipment may
not automatically set an anonymous 24-bit address or set a blank (Not
Available per RTCA/DO-282()) call sign based solely on pilot selection of
the 1200 Mode 3/A code.
 
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As a Flightaware flight feeder provider with a premium account, I can assure you it does not if you have Mode C an you are squawking 1200 in anonymous mode.
I've tried it, and you're just mistaken. I took off from a Class C with the switch in the anonymous mode. When I left the Class C and approach told me to squawk VFR, I switched to 1200 and continued to my destination. When I got home, I looked up my track on Flightware and it was all there from end-to-end. The return trip only showed my track from the point when I called up Approach and was assigned a code.

I went up today for a couple of touch and goes and tower had me squawk a local code rather than 1200. Now I'm wondering if that was so I can't be "anonymous". That really doesn't make sense. I'll have to ask them.
 
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Although the above seems quite firm, please note the document is an advisory circular. Like it says on the first page, "This AC is not mandatory and does not constitute a regulation."

Anyone know of a regulation?
The FAA's regulation for UAT transponder approval is TSO-C154. That document is essentially a shell for the industry-standard DO-282 UAT Minimum Operational Performance Specification (MOPS) mentioned above, so although they're in an AC, those statements referenced from DO-282 are almost certainly regulatory.

Last I checked, RTCA will be happy to sell you a paper copy of DO-282 for only $595...

HTH

Dave
(Consultant DER)
 
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Identity Transmission

Shielding your identity (aircraft or otherwise) from the general public is one thing. It is the ONLY reason for the anonymous modes in use or being proposed. You are fooling yourself if you think you can shield your aircrafts identity from the FAA while your transponder is turned on.
 
First, because we live in America where privacy and our right to travel freely without interference is fundamental.

I will never understand why so many people today in America are not just willing, but overtly so eager to flush away all of their rights. I guess freedom is simply too frightening for some people.
 
Sometimes when flying formation ATC will request wing men sqwawk standby. If the wingman has ADS-B out technically ATC should not make the request and the pilot should not do it.

It probably sets off all of their collision alert warnings. Wait for it, some genius will declare all transponders must allow a "formation" setting, specifying which aircraft is lead, and every airplane will again require a transponder upgrade.
 
There is a multi-year aged issue with ADS-B out and aerobatics the FAA and EAA and IAC have been working. When inverted/rolling/manuevering enough you lose position source of GPS. This can trigger the heads up/nastygram FAA contact.

https://www.iac.org/news/2016-12-17-ads-b-update

Formation and Aerobatics were shockingly (sarcasm font) overlooked to some extent so far.
 
Along with acro and formation aircraft being ignored so were non engine-driven electrical aircraft. We have a Luscombe hangared at Class C and we keep a battery on a charger so we can use a Mode C transponder to get in and out of C and then turn it off when outside of C. All legal and plays well with others. We now have to move our airplane as we cannot equip with ADS-B since it requires the "always on", not just while in rule airspace. That would deplete our battery and trigger a violation. :mad: Meanwhile Jeff Bezos wants to launch Amazon drones that claim they can avoid other aircraft since real airplanes fly high and have ADS-B out. Our Luscombe rarely gets over 400' AGL and doesn't have ADS-B out.
 
Shielding your identity (aircraft or otherwise) from the general public is one thing. It is the ONLY reason for the anonymous modes in use or being proposed. You are fooling yourself if you think you can shield your aircrafts identity from the FAA while your transponder is turned on.
How will the FAA know who you are when in anonymous mode squawking 1200?
No identifying information is being transmitted.
 
How will the FAA know who you are when in anonymous mode squawking 1200?
No identifying information is being transmitted.
If you took off from an uncontrolled area and never fly in any areas requiring a transponder code other than 1200, then you may be right.

If you have to pick up a code anywhere, your entire flight can now be tagged with your ident if someone goes back and reviews the logs.
 
Wow, this thread is like a winding road on the coast. It wears out my tires with all the drift. Privacy went away years ago.
 
How will the FAA know who you are when in anonymous mode squawking 1200?
No identifying information is being transmitted.

Are you sure about that? I think that all it suppresses is your N number; isn't the raw code of the ADSB unit (which is tied to your N number in the FAA database) still transmitted?
 
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