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Formation and ADS-B Out

FasGlas

Well Known Member
Now that there's lots of planes with ADS-B out installed and I believe we've established that ADS-B out must be shut off during formation flights, same as transponders, how are pilots doing this or planning on doing this?
Since anonymous mode does not shut off the ADS-B transmission and shutting off the entire ADS-B transceiver also shuts off ADS-B IN what are formation pilots doing or planning on doing? I don't know of any ADS-B transceivers that allow just the out to disabled, unless using 2 separate units ( In only and out only)...
 
It really depends on your equipment and particular installation. Transponder - OFF or STBY could do it for my GTX-327 / GDL-82 setup. And not sure I need ADS-B in during formation work, so pulling the common circuit breaker would kill it all.
 
It really depends on your equipment and particular installation. Transponder - OFF or STBY could do it for my GTX-327 / GDL-82 setup. And not sure I need ADS-B in during formation work, so pulling the common circuit breaker would kill it all.

Same thought. No need for ADSB In when you should be looking out the window. I can just turn off transponder or turn it to standby. No transponder, no ADSB out. Pulling the common breaker also solution.
 
While it flies in the face of common sense and normal practice, for formation the FAA allows ADSB Out to be turned off only when ATC requests it. Even that had to come as a rule change. See https://www.federalregister.gov/doc...cast-ads-b-out-equipment-and-use-requirements
At one point I heard they were also going to require a switch to turn it off, i.e. not a circuit breaker. It doesn't look like the switch requirement made it to the rule change. I still turn it off flying wing but that's the rule.
 
This was an important exemption to get. ATC wanted it more than we did. With respect to how to do it. Pull the breaker if you have an all-in-one transponder/ADS-B Out. I don't know if these all-in-ones have a standby or off button that is truly standby/off. STCs such as the GDL 82 have the unit use the same breaker as the transponder so that would work too. In the case of Freeflight those use a separate breaker.

With separate ADS-B in and out systems (like a GDL 82 with GDL 52) the "in" would still be on. But as mentioned by others "in" would be totally irrelevant to me if I were in formation.

Anonymous mode has nothing to do with this. Anonymous doesn't mean you are invisible or ADS-B is off. It means you are still visible and in the system save and except any identifying information is randomized (ICAO code, N number etc...). So whether anonymous mode is enabled or not the system would still need to be turned off as a formation wing man.

This is a good development. Now that 2020 is upon us the FAA is starting to act like they are listening (unlike the last 5 years). I am working on another petition for exemption to the "always on" rule for non engine-driven electrical aircraft that want to fly within rule airspace with compliant "out" and then turn it off when out of rule airspace. AOPA legal team has been meeting with the FAA on it and we just used my Luscombe as the official petition aircraft that will set a precedent for other antique aircraft.

Jim
 
Additional Guidance for ADS-B and Formation Flight

Recently published Advisory Circular has additional guidance for ADS-B and formation flight: https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_90-114B.pdf

4.3.1.3 deals with formation operations, of which the second part I believe now gives us broad direction/approval for wingmen to kill their ADS-B during formation flight, without direct permission from ATC for the specific flight.


4.3.1.3 Formation Operations. ATC uses established transponder and ADS-B
transmission procedures when participating in formation operations. Per the
Aeronautical Information Manual (AIM) paragraph 4-1-20, if the formation
flight is receiving ATC services, pilots can expect ATC to direct all non-lead
aircraft to ?STOP SQUAWK,? and should not do so until instructed. For
visual flight rules (VFR) formation flights not receiving ATC services, ATC
directs that only the lead aircraft should squawk the assigned beacon code
(1200). All other aircraft should disable transponder and ADS-B transmissions
once established within the formation.
 
...

This is a good development. Now that 2020 is upon us the FAA is starting to act like they are listening (unlike the last 5 years). I am working on another petition for exemption to the "always on" rule for non engine-driven electrical aircraft that want to fly within rule airspace with compliant "out" and then turn it off when out of rule airspace. AOPA legal team has been meeting with the FAA on it and we just used my Luscombe as the official petition aircraft that will set a precedent for other antique aircraft.

Jim
Be careful what you ask for.

You might trigger the FAA to mandate battery powered transponders and ADS-B in all non-electric aircraft, which would be very bad!
 
Be careful what you ask for.

You might trigger the FAA to mandate battery powered transponders and ADS-B in all non-electric aircraft, which would be very bad!

That's a fair question given the lack of detail in my post. You dont specify "where" in your statement where that could happen. And it would never happen, unless your statement implies "within Rule Airspace". Which is exactly our goal. Right now non engine-driven electrical aircraft cannot operate in Rule Airspace except for within the Mode C veil of Class B, outside of B. But never within any other Rule Airspace (Class C, A, ADIZ, etc..). Until non-electrical aircraft are allowed to turn off ADS-B equipment when outside of Rule Airspace that shunning applies. Period. So we are reducing that limitation allowing non-electrical acess to Rule Airspace at the option of the aircraft owner where there is none currently. This is a petitioning for exemption for this airplane only. Carefully crafted by the AOPA legal department using our aircraft as a poster child. Once the ice is broke it can become a precedent and create a template for any other non-electrical owner who desires acess to Rule Airspace or just wants the simple option to turn off installed equipment outside of Rule Airspace for whatever other reason. This has nothing to do with a change in regulation but rather provides a one-time one-ship exemption analogous to the proven existing LOA process while keeping regs in place.

The new ADS-B rule does not allow any equipped aircraft to ever turn off ADS-B out unless you are parked without the engine running. Regardless of location. Wthin Rule Airspace or not.
Anywhere on the surface or in the air, in the whole United States. Whether a maintenance run-up or taxiing on the ground 200 miles from civilization.

So this request is simple. Allow our aircraft to turn off ADS-B when outside of Rule Airspace just like we could do for Mode C in the past. The AOPA legal team is escorting this petiton through the FAA as a yes/no request with deliberate language. Our membership dollars at work. If anybody wants to read the petition I can send a link.
 
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For visual flight rules (VFR) formation flights not receiving ATC services, ATC directs that only the lead aircraft should squawk the assigned beacon code(1200). All other aircraft should disable transponder and ADS-B transmissions once established within the formation.

I read this to mean that when not in contact with ATC during VFR formation flights the standing guidance is for wingmen to disable transponder and ADS-B out.


As some have already pointed out there are a number of issues with this guidance.* For example, my EFB receives*its GPS and ADS-B-in data from my ADS-B system.* Additionally*my Uavionix system is not switched.* I can only disable it by pulling the breaker. (What about those systems on a fuse that is not readily accessible?)* * If you happen to have the Uavionix Sky Beacon it is powered with the nav lights and cannot be separated.* On certified aircraft with this system the STC requires the nav lights and ADS-B to be on at all times.*

What about maneuvering formations where you go from standard to non-standard formation, I.E. Extended trail with over the top maneuvering?*


Some systems or components(mainly some encoders) have a several minute warm up*time which effectively precludes quickly turning the system back on, not to mention taking eyes off of the plane in front of you.

I could make some comments about the FAA not thinking this through before they mandated ADS-B and published the rules, which they are now changing, but it would not do much good. I am afraid that this is setting people up for unintentional violations, which now that we have ADS-B transmitting identification it makes it much easier for the FAA to do from an office while looking at ADS-B data on their computer.

V/R,

John
 
I could make some comments about the FAA not thinking this through before they mandated ADS-B and published the rules,

There are a lot of things regarding ADS-B and its implementation that the FAA doesn't seem to have thought through or considered.

- Operator privacy
- Formation flight
- Aircraft with non-engine-powered electrical systems that want to use ADS-B (gliders, antiques, ultralights, etc.)
- Overall system security
- Drones/UAS
- Overall system capacity/congestion

And so on.


However, like most FAA rules (and indeed, most legislation and regulation in general) they make a set of rules expecting one outcome, and get a different outcome. Go look at the Light Sport rules and what the FAA intended vs. what it got.
 
Unclear

For visual flight rules (VFR) formation flights not receiving ATC services, ATC directs that only the lead aircraft should squawk the assigned beacon code(1200). All other aircraft should disable transponder and ADS-B transmissions once established within the formation.

I read this to mean that when not in contact with ATC during VFR formation flights the standing guidance is for wingmen to disable transponder and ADS-B out.


As some have already pointed out there are a number of issues with this guidance.* For example, my EFB receives*its GPS and ADS-B-in data from my ADS-B system.* Additionally*my Uavionix system is not switched.* I can only disable it by pulling the breaker. (What about those systems on a fuse that is not readily accessible?)* * If you happen to have the Uavionix Sky Beacon it is powered with the nav lights and cannot be separated.* On certified aircraft with this system the STC requires the nav lights and ADS-B to be on at all times.*

What about maneuvering formations where you go from standard to non-standard formation, I.E. Extended trail with over the top maneuvering?*


Some systems or components(mainly some encoders) have a several minute warm up*time which effectively precludes quickly turning the system back on, not to mention taking eyes off of the plane in front of you.

I could make some comments about the FAA not thinking this through before they mandated ADS-B and published the rules, which they are now changing, but it would not do much good. I am afraid that this is setting people up for unintentional violations, which now that we have ADS-B transmitting identification it makes it much easier for the FAA to do from an office while looking at ADS-B data on their computer.

V/R,

John

To add to your questions, I have some of my own:

1. When departing a controlled airport VFR, are wingman required to squawk until told otherwise? (I assume airport operations at a controlled airport constitutes "receiving ATC services".

2. When an enroute/VFR flight squawking 1200 requests flight following, are all wingmen in the flight required to turn their transponders/ADSB out on until requested to turn them back off by ATC?

3. When a VFR flight returns to a a controlled airport/airspace and lead contacts the tower, are wingmen required to turn their transponders/ADSB out back on?

I agree that it doesn't seem like the ADSB operational requirements were very well thought out and now they're making up the rules as they go along...

My take is that we aren't in violation of the regs as long as the transponders/ADSB are on so I leave it on until told otherwise (A/C's are not regulatory). Maybe if the controllers are annoyed enough by this, they'll fix the regs for good!

Skylor
 
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To add to your questions, I have some of my own:

1. When departing a controlled airport VFR, are wingman required to squawk until told otherwise? (I assume airport operations at a controlled airport costitutes "receiving ATC services".

2. When an enroute/VFR flight squawking 1200 requests flight following, are all wingmen in the flight required to turn their transponders/ADSB out on until requested to turn them back off by ATC?

3. When a VFR flight returns to a a controlled airport/airspace and lead contacts the tower, are wingmen required to turn their transponders/ADSB out back on?

I agree that it doesn't seem like the ADSB operational requirements were very well thought out and now they're making up the rules as they go along...

My take is that we aren't in violation of the regs as long as the transponders/ADSB are on so I leave it on until told otherwise (A/C's are not regulatory). Maybe if the controllers are annoyed enough by this, they'll fix the regs for good!

Skylor

skylor asks the big question. the ac, which he points out correctly is not regulatory tells you to violate a far: far 91.225

(2) Otherwise directed by ATC when transmitting would jeopardize the safe execution of air traffic control functions.

it says when not VFR not using ATC services to turn it off. that is in direct violation of 91.225. which says ATC can tell you to turn it off not some AC.

im with skylor. its their mess, mine stay on until they fix it legally. will be great hearing ATC at osh tell everybody to turn it off over the already crowded radio.

bob burns
RV-4 N82RB
 
ATC treatment of Formation Flights

ATC has treated formation flights as a single entity for many years. Long before ADS-B, only the lead would squawk. Or in the case of longer in-trail "formations" (usually large aircraft), the lead and the last aircraft might squawk.

When a formation flight taxies out, the entire flight is cleared to taxi as one entity.

When a formation flight is cleared for takeoff, the entire formation is cleared, as if one entity. Example: A 60-ship flight of T-6 aircraft was cleared for takeoff at Oshkosh years ago. One transmission, one "entity" for ATC.

When you arrive at an airport as a flight of four, you are cleared to land as a flight, and the normal runway separation standards don't apply.

So it would seem logical that when in formation, ATC would like to treat you as a single entity. I can't imagine that they really want aircraft in close proximity squawking and "ADSB-ing". Surely it will trigger collision warnings in their system.

A little common sense goes a long way to interpreting the rules. No matter how many times rules are written and re-written, if you are pedantic enough, you can find some conflict in the rule.

Flame suit on...........
 
What Pete said is what I was thinking. Annoying the controllers by having everyone turn their ADS-B on and have to be told to turn it off again is just being an *ss. The controllers have no direct control over the regs, they're just the ones who have to live with them.

You know that they'll tell you to turn it off again, so just leave it off unless you're lead.
 
^^This....

Doesn't matter if you are talking with an ATC facility or not, their collision warning systems are still going to alert if it sees two or more aircraft in close proximity to one another. Imagine having to deal with this day in and day out.

Any time you are operating as a formation flight (FAA defines that as w/in 1NM of another aircraft on purpose) the wingmen need to disable their transponder and ADS-B signals to prevent nuisance collision warnings.

If you have followed the regs, you briefed your formation flight prior to takeoff, the lead assumes all responsibility for adherence to the FARs, that includes, VFR weather minimums and cloud clearances, equipment requirements, etc.

To ATC and the FAA you are a single entity until that time that you break up the formation. That's why when your buddy pulls up along side of you in flight unexpectedly, it's not a great idea.
 
Squawk vs.??

...I can't imagine that they really want aircraft in close proximity squawking and "ADSB-ing".

Since transponders were originally conceptualized as a "parrot" system, the term "squawk" emerged. Since ADS-B is viewed by some as a chicken s**t concept, maybe the term should be "cluck"
"N123, approach, stop squawk stop cluck"
:D
 
FAA Flight Standards has a computer that monitors all ADS-B out transmissions within the coverage areas. If one is sending data that is out of tolerance, it will flag, and multiple fails will result in a letter to th aircraft owner
 
Anyone know who actually monitors ADS-B for compliance? Anyone been busted for non-compliance since the 2020 mandate?

An FAA "red light" computer in Washington DC (not OKC). I know 4 aircraft owners who got nastygrams from said computer last year. I helped draft a response for one I did the installation on. It was a brand new dual G5 system and the #1 G5 was used as the digital encoder for the transponder/ADS-B system and the G5's internal air data computer went haywire within 10 hours resulting in the ADS-B altitude transmission to swing from 300 ft MSL to 14,000 ft MSL within two seconds and then all points in between. The airplane was taking off and departing an uncontrolled field in the LA basin and lit up ATC panels like a Christmas tree.

I attended the Air Boss briefing at Oshkosh and they told the performers that if their aircraft was equipped with ADS-B it had to be on during their performance from engine start on. Air Boss agreed it was ridiculous, especially in Waivered Airspace but nobody knew how to explain all that to the robocop enforcement computer in DC. As we waited our turn with the engine idling I could watch the preceeding performer on my aera 660 as he did an acro routine.

That crazy computer is the same reason why the AirVenture NOTAM approach proceedure instructs ADS-B equipped aircraft to never squawk standby, much to the chagrin of Center and local ATC facilities.

Jim
 
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ATC has treated formation flights as a single entity for many years. Long before ADS-B, only the lead would squawk. Or in the case of longer in-trail "formations" (usually large aircraft), the lead and the last aircraft might squawk.

When a formation flight taxies out, the entire flight is cleared to taxi as one entity.

When a formation flight is cleared for takeoff, the entire formation is cleared, as if one entity. Example: A 60-ship flight of T-6 aircraft was cleared for takeoff at Oshkosh years ago. One transmission, one "entity" for ATC.

When you arrive at an airport as a flight of four, you are cleared to land as a flight, and the normal runway separation standards don't apply.

So it would seem logical that when in formation, ATC would like to treat you as a single entity. I can't imagine that they really want aircraft in close proximity squawking and "ADSB-ing". Surely it will trigger collision warnings in their system.

A little common sense goes a long way to interpreting the rules. No matter how many times rules are written and re-written, if you are pedantic enough, you can find some conflict in the rule.

Flame suit on...........

While I agree with you in principle, that is clearly not what the FAA wrote in AC 90-114B:

For visual flight rules (VFR) formation flights not receiving ATC services, ATC directs that only the lead aircraft should squawk the assigned beacon code(1200). All other aircraft should disable transponder and ADS-B transmissions once established within the formation.

They could have simply stated "For formation flights ATC directs that only the lead aircraft should squawk the assigned or VFR beacon code. All other aircraft should disable transponder and ADS-B transmissions once established within the formation." But they didn't state it this way which leads me to believe that the rule makers don't want wingmen to "strangle the parrot" in the other situations.

Skylor
 
One other thing...
Once the FAA computer decides your ADS-B is "non-compliant", it is considered to be unworthy until you report evidence that your ADS-B out has been repaired.
Last time I looked at the FAA data, about 8% of ADS-B out systems had a non-compliant event.
 
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