What is "participating VFR" ?

kicktireslightfires

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kicktireslightfires
What exactly does “participating VFR” mean when the FAR talks about ATC providing separation as in when you’re IFR you receive separation from other IFR traffic and participating VFR traffic? Does that mean active flight following or does it mean ADS-B or does it just mean those with at minimum a mode C transponder? And further, why would any of that be needed in a radar environment? Within radar coverage, can’t ATC separate IFR aircraft from any other aircraft whether they have a transponder or not? A transponder and ADS-B only supplements the radar data, right? It doesn’t require a transponder for ATC to see traffic on their radar I assume.
 
Participating VFR means VFR talking to ATC. Transponder or adsb status has no bearing on whether an aircraft is participating or not.

Primary radar requires different separation standards from non radar. It also requires communication with the pilot to verify target, usually by a change of heading. All radar identification requires altitude verification.

ATC can't anticipate what a non-participating aircraft might do regarding altitude speed or heading. How could they separate from non participating aircraft aside from giving away high swaths of airspace?
 
My understanding of "paticipating" VFR means those VFR aircraft that are talking to ATC and have been given a discrete code (ie. they are positively identified). I don't know how ADSB has changed the way ATC works traffic around aircraft they aren't talking to but have ADSB. When ATC has a radar target that is squawking 1200 and mode c but has not contacted them, ATC might still point out that traffic to participating aircraft at that position and altitude but always with the caveat "unverified." ATC radar, at least the ones I'm familiar with, are not 3D (they only get range and azimuth), hence the need for mode C to give them altitude. Some military radars, since they are designed to ultimately guide a missile or projectile to shoot down an aircraft, are designed to track an uncooperating aircraft in 3 dimensions so they have range, azimuth and altitude. While ATC radar can skin paint an aircraft, a transponder provides the ATC radar with a much more reliable return and in some instances, the controller may choose to filter out all returns other than transponder returns to declutter his scope from ground or atmospheric interference.
 
Just because ATC can see a tail # w/ADSB, they have no idea what, if any freq they might monitoring. They have no way to talk to them.
 
And just to underline the point Brad made, non-participating VFR aircraft can’t be predicted.

@kicktireslightfires - if you were a controller would you pass an IFR aircraft above an observed but non-participating VFR aircraft with 1,000-foot separation- and realize you’re betting your job/performance rating in addition to the safety of those involved.
 
What exactly does “participating VFR” mean when the FAR talks about ATC providing separation as in when you’re IFR you receive separation from other IFR traffic and participating VFR traffic? Does that mean active flight following or does it mean ADS-B or does it just mean those with at minimum a mode C transponder? And further, why would any of that be needed in a radar environment? Within radar coverage, can’t ATC separate IFR aircraft from any other aircraft whether they have a transponder or not? A transponder and ADS-B only supplements the radar data, right? It doesn’t require a transponder for ATC to see traffic on their radar I assume.
What FAR says that?
 
A few weeks ago I was out in our practice area. I was tuned into Anchorage Approach frequency, but I wasn't talking to them and didn't have a squawk. This is what I typically do out there: I listen, and have the frequency tuned in in case I have a problem.

Randomly, they called me!:
"Aircraft <my tailnumber>, I don't know if you're on frequency, but you've got traffic... <blah blah blah>"
I replied that I was on the frequency, and we talked about the traffic.

This had never happened to me before... but I suppose that since I've got ADS-B, they could identify my tail number even though I wasn't "participating". I was thankful for their transmission in the blind -- traffic significant enough they thought to try making the call. A "new feature" of ADS-B, I suppose.

After they pointed out a few more traffics, I told them, "You might as well give me a squawk at this point..." :)
 
Sort of like promotions being limited to participating McDonald's locations.

I wanna open a McDonald’s and not participate in anything. I wanna be a stubborn McDonald’s owner. “Cheeseburgers?” “Nope! We got spaghetti, and blankets. And we are not affiliated with that clown.
 
Randomly, they called me!:
"Aircraft <my tailnumber>, I don't know if you're on frequency, but you've got traffic... <blah blah blah>"
I replied that I was on the frequency, and we talked about the traffic.

Similar thing happened to me. A plane is talking to HKY tower and someone asked about traffic.

HKY: There's a navion 5327K out there, but I am not talking to him.
ME: You're talking to him now. Eight miles east 2500 landing Hickory.
 
A few weeks ago I was out in our practice area. I was tuned into Anchorage Approach frequency, but I wasn't talking to them and didn't have a squawk. This is what I typically do out there: I listen, and have the frequency tuned in in case I have a problem.

Randomly, they called me!:
"Aircraft <my tailnumber>, I don't know if you're on frequency, but you've got traffic... <blah blah blah>"
I replied that I was on the frequency, and we talked about the traffic.

This had never happened to me before... but I suppose that since I've got ADS-B, they could identify my tail number even though I wasn't "participating". I was thankful for their transmission in the blind -- traffic significant enough they thought to try making the call. A "new feature" of ADS-B, I suppose.

After they pointed out a few more traffics, I told them, "You might as well give me a squawk at this point..." :)

With ADS-B these days, this seems to be happening more. In the past you were a random primary or even 1200 target. Now ATC can see a data block for you whether you are talking to them or not. But if you aren't talking to them, they cannot confirm the reported altitude is indeed correct, and they have no way of knowing your intentions.

The unanswered question at this point, is if ATC cold calls you, do you have to comply with any instructions?
 
Sounds like you’re reading the definition of a TRSA. In order to receive the approved separation for a VFR, you must “participate.” Meaning, be up their frequency.

08230283-38C8-4DA2-87D2-7C824625DD07.jpeg
 
With ADS-B these days, this seems to be happening more. In the past you were a random primary or even 1200 target. Now ATC can see a data block for you whether you are talking to them or not. But if you aren't talking to them, they cannot confirm the reported altitude is indeed correct, and they have no way of knowing your intentions.

The unanswered question at this point, is if ATC cold calls you, do you have to comply with any instructions?
You are supposed to. But ya can’t really get in trouble for not doing it if you don’t talk to them and let them know you were even listening.
 
Sounds like you’re reading the definition of a TRSA. In order to receive the approved separation for a VFR, you must “participate.” Meaning, be up their frequency.

View attachment 108661
That’s what I was thinking maybe he was doing to. Although I’m not sure ‘participating’ doesn’t show up elsewhere also. @kicktireslightfires , when you said FAR in your post #1, did you mean AIM?
 
A few weeks ago I was out in our practice area. I was tuned into Anchorage Approach frequency, but I wasn't talking to them and didn't have a squawk. This is what I typically do out there: I listen, and have the frequency tuned in in case I have a problem.

Randomly, they called me!:
"Aircraft <my tailnumber>, I don't know if you're on frequency, but you've got traffic... <blah blah blah>"
I replied that I was on the frequency, and we talked about the traffic.

This had never happened to me before... but I suppose that since I've got ADS-B, they could identify my tail number even though I wasn't "participating". I was thankful for their transmission in the blind -- traffic significant enough they thought to try making the call. A "new feature" of ADS-B, I suppose.

After they pointed out a few more traffics, I told them, "You might as well give me a squawk at this point..." :)

Similar thing happened to me. A plane is talking to HKY tower and someone asked about traffic.

HKY: There's a navion 5327K out there, but I am not talking to him.
ME: You're talking to him now. Eight miles east 2500 landing Hickory.

Yep. I was VFR, squawking 1200 last week, monitoring Norcal, heard them identify my plane as traffic to another. Said-"I'm that traffic, have aircraft in sight" Identified myself and asked for flight following...
 
That’s what I was thinking maybe he was doing to. Although I’m not sure ‘participating’ doesn’t show up elsewhere also. @kicktireslightfires , when you said FAR in your post #1, did you mean AIM?
In the context of providing separation services, sounds like TRSA. But if you check out AIM 4-1-18, you can see the discussion goes beyond TRSA. There are some basic Class Ds here and there which provide radar sequencing and separation to aircraft which all Approach without being TRSA. Pueblo, CO was one when I was there.

and yeah, most likely meant AIM. I don't think TRSA appears in the FAR.
 
In the context of providing separation services, sounds like TRSA. But if you check out AIM 4-1-18, you can see the discussion goes beyond TRSA. There are some basic Class Ds here and there which provide radar sequencing and separation to aircraft which all Approach without being TRSA. Pueblo, CO was one when I was there.

and yeah, most likely meant AIM. I don't think TRSA appears in the FAR.
Ah ha, there it is. Not only in 4-1-18 b.TRSA, but before that in a. 5. (a)
 
The Letter to Airmen for practice instrument approaches at KHKY states:

The Air Traffic Controller's responsibility to provide standard IFR separation for participating VFR aircraft begins at the point...
 
And just to underline the point Brad made, non-participating VFR aircraft can’t be predicted.

@kicktireslightfires - if you were a controller would you pass an IFR aircraft above an observed but non-participating VFR aircraft with 1,000-foot separation- and realize you’re betting your job/performance rating in addition to the safety of those involved.

Not my question, but I'll chip in: it depends. If there is a VFR aircraft I'm not talking to that has been flying along at 7500, I think it is safe to descend the IFR aircraft to 8000 and issue traffic. If the VFR appears to be in a climb where altitude separation may not be feasible, I'd probably turn the IFR aircraft and issue a descent.

Please keep on mind that with few exceptions, outside of Class B and Class C, there is no separation standard for IFR/VFR or VFR/VFR aircraft. Controllers must not allow the aircraft to come in unsafe proximity to one another. This is a first priority duty.
 
Another use of "participating aircraft" that I've seen is at Diego Garcia, a US military base on a coral atoll in the Indian Ocean.

The airspace around Diego is uncontrolled from the surface up to FL245. Since there are IFR operations in and out of Diego, military and civilian, Diego tower offers optional "IFR traffic advisory service to participating aircraft".
 
So, if I'm on flight following and am a Participating VFR Aircraft.......

.......do I get a participation trophy?
 
Nope. Why would you? Let’s assume you’re not violating any airspace at the time they call. You know. Because POA.

I think this question came up here or on another forum not too long ago. Someone was flying somewhere in Socal I believe, when the controller cold called them using the tail number from his ADS-B. Once they responded the controller provided a squawk code, then started vectoring the VFR aircraft due to traffic. They were in Class E airspace, albeit a congested area, and had not requested any VFR services.

So the question was, you normally have to follow ATC instructions, but what if you didn't ask for it in the first place?

Or just pretend you didn't hear it and weren't monitoring the frequency?
 
Or just pretend you didn't hear it and weren't monitoring the frequency?

That's a good question. I think the technical answer is you don't have to. Since you may or may not have been monitoring approach (or whatever the frequency).

Practically - if ATC called me up and asked if I was on freq and then gave me a code and started vectoring me for traffic... I would answer. It gets busy like that in the airspace just outside the SFRA here in DC. I like all the SA I can get. But I better get my VFR participation trophy mailed to me after. :rofl:
 
I think this question came up here or on another forum not too long ago. Someone was flying somewhere in Socal I believe, when the controller cold called them using the tail number from his ADS-B. Once they responded the controller provided a squawk code, then started vectoring the VFR aircraft due to traffic. They were in Class E airspace, albeit a congested area, and had not requested any VFR services.

So the question was, you normally have to follow ATC instructions, but what if you didn't ask for it in the first place?

Or just pretend you didn't hear it and weren't monitoring the frequency?
Treat them like a lot lizard. If you don’t want their services ignore them… once you start talking to them an objective observer could argue you solicited services.
 
Treat them like a lot lizard. If you don’t want their services ignore them… once you start talking to them an objective observer could argue you solicited services.
If ATC goes to the trouble of calling for me in the blind I'm going to assume it's something important enough to respond immediately, regardless of whether I want radar services.

ATC doesn't call out 1200 traffic looking for more aircraft to work just for the fun of it.
 
If ATC goes to the trouble of calling for me in the blind I'm going to assume it's something important enough to respond immediately, regardless of whether I want radar services.

ATC doesn't call out 1200 traffic looking for more aircraft to work just for the fun of it.
I was responding to the question “do I have to respond” not “is it a good idea to respond” or “am I a dumbass if I ignore atc?”

If you ask what I would do then the answer is I would very quickly become a participant in ATC services to ensure my parts all stayed attached.

- Tarheelpilot
Answering just the question that was asked.
 
I was responding to the question “do I have to respond” not “is it a good idea to respond” or “am I a dumbass if I ignore atc?”

If you ask what I would do then the answer is I would very quickly become a participant in ATC services to ensure my parts all stayed attached.

- Tarheelpilot
Answering just the question that was asked.
I had to look up the (urban dictionary) meaning of "lot lizard" but my point is even if I didn't want radar services, the novelty (and presumed urgency) of ATC cold calling me would be compelling enough to answer.

Even with ADS-B, I suspect ATC cold calling to be exceptionally rare. I suspect when it does happen it's because you tried to check in on the frequency but the controller was to busy to acknowledge you, or you just got approved for a frequency change and the controller hoped you might not have switched over yet.

What seems to be most common is motoring along monitoring approach frequency and then checking in when ATC calls out traffic on a target that matches your heading and altitude.
 
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