Requirement to advise for traffic in the IFR system?

Fearless Tower

Fearless Tower

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Fearless Tower
Curious what the actual requirement is for controllers to advise aircraft under IFR of traffic.

I have been noticing an increasing trend among controllers in the Southwest to not advise me of nearby traffic while I am flying IFR in the system. Sometimes, I'll hear the controller advise the jets of me, but never mention the jet traffic to me.

The other day I had an MV-22 pass relatively close by (opposite direction) near Thermal and I asked the approach controller if he was tracking him - he responded that he was 1000 feet above me and talking to another controller in a tone that suggested that I was silly for being concerned.

What gives? Is this just another effort to encourage GA not to use the system?

Granted, 1000' separation is still a healthy safety margin, but still, would have been nice to have a heads up.
 
Fearless Tower said:
Curious what the actual requirement is for controllers to advise aircraft under IFR of traffic.

I have been noticing an increasing trend among controllers in the Southwest to not advise me of nearby traffic while I am flying IFR in the system. Sometimes, I'll hear the controller advise the jets of me, but never mention the jet traffic to me.

The other day I had an MV-22 pass relatively close by (opposite direction) near Thermal and I asked the approach controller if he was tracking him - he responded that he was 1000 feet above me and talking to another controller in a tone that suggested that I was silly for being concerned.

What gives? Is this just another effort to encourage GA not to use the system?

Granted, 1000' separation is still a healthy safety margin, but still, would have been nice to have a heads up.
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See Order JO 7110.65T Air Traffic Control para 5-1-8. MERGING TARGET PROCEDURES.
 
I watched them almost colide me with one of our flightschool planes, we were both on with the same controller on different frequencies popping in and out of the clouds and untill I said "eight one echo has the traffic" he didn't do a damn thing.

now after I said something a rather hurried controler told the school 172 (who was ahead of us and below but climbing on a wonderful intercept course) to "Stop your climb!"
 
Remember IFR is not guaranteed separation from VFR aircraft, despite what many think. When its VMC you are responsible for your own separation.
 
Correct! and that even applies to tower ops where the mandate is "separation on the runway....". Many moons ago, DVT apologized on air for forgetting about a cessna on the opposite base, and when I got down and quit cussing, I called the tower and "had a discussion".

The buffet was SO near and the propellor was SO loud, I looked for paint transfer for about 15 minutes. I never trust a controller blindly as a result. NEVER never never.

I was used to the MIL controllers, who are held to separation, period.

As in, "Yer own yer own, son".
 
SkyHog said:
Remember IFR is not guaranteed separation from VFR aircraft, despite what many think. When its VMC you are responsible for your own separation.
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Yes, I know that, which is why I keep my head on a swivel, but many of the cases I've noticed involve two aircraft in the IFR system.

I'm just curious in the requirement to advise of traffic since I have noticed a significant decline in this service. Unfortunately, unless I am misreading it, what Roncachamp posted seems to refer to aircraft above 10,000. Surely there must be a delineated requirement for traffic below 10k....that's where all the terminal areas are!

Also, this isn't a matter of under-staffed or overworked ATC.....most of these cases seem to be in the enroute phase or on the fringes of the TRACON area and the freq is not clobbered.
 
Fearless Tower said:
Yes, I know that, which is why I keep my head on a swivel, but many of the cases I've noticed involve two aircraft in the IFR system.

I'm just curious in the requirement to advise of traffic since I have noticed a significant decline in this service. Unfortunately, unless I am misreading it, what Roncachamp posted seems to refer to aircraft above 10,000. Surely there must be a delineated requirement for traffic below 10k....that's where all the terminal areas are!

Also, this isn't a matter of under-staffed or overworked ATC.....most of these cases seem to be in the enroute phase or on the fringes of the TRACON area and the freq is not clobbered.
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If the traffic is not in IMC the same applies.
 
SkyHog said:
If the traffic is not in IMC the same applies.
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The same what applies? If you are referring to 'see and avoid' as I said, I am well aware of that....what I am wondering is what the controller's responsibility is in that situation. He has some - what is it, that is my question.

If two aircraft under IFR collide in VMC, the pilots are naturally going to get the bulk of the blame, but the controller will not come away unscathed.
 
Fearless Tower said:
If two aircraft under IFR collide in VMC, the pilots are naturally going to get the bulk of the blame, but the controller will not come away unscathed.
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If two aircraft under IFR collide in VMC the controller may be the only one available to blame.
 
Fearless Tower said:
The same what applies? If you are referring to 'see and avoid' as I said, I am well aware of that....what I am wondering is what the controller's responsibility is in that situation. He has some - what is it, that is my question.

If two aircraft under IFR collide in VMC, the pilots are naturally going to get the bulk of the blame, but the controller will not come away unscathed.
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Why would the controller get any blame when he is not required to provide separation in VMC?
 
SkyHog said:
Why would the controller get any blame when he is not required to provide separation in VMC?
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Because the controller is required to provide separation between 2 IFR planes. It is ultimately up to the planes to maintain separation in VMC, but the controller does have some responsibility for the separation.
 
Greg Bockelman said:
Because the controller is required to provide separation between 2 IFR planes. It is ultimately up to the planes to maintain separation in VMC, but the controller does have some responsibility for the separation.
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The controller's responsibility for separation between IFR aircraft in VMC is exactly the same as his responsibility between IFR aircraft in IMC.
 
Fearless Tower said:
The same what applies? If you are referring to 'see and avoid' as I said, I am well aware of that....what I am wondering is what the controller's responsibility is in that situation. He has some - what is it, that is my question.

If two aircraft under IFR collide in VMC, the pilots are naturally going to get the bulk of the blame, but the controller will not come away unscathed.
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I'm Mr. Skeptic, but can't we assume that if aircraft collide and both are not under IFR control, the weather at the time will automatically be VMC? :idea:

Course, if it wasn't VMC, the VFR pilot would have been in violation...but you can have the IFR pop out of a cloud and hit the VFR that had legal cloud separation.
 
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roncachamp said:
The controller's responsibility for separation between IFR aircraft in VMC is exactly the same as his responsibility between IFR aircraft in IMC.
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Yep, until the pilots accept the responsibility by acknowledging that they have the traffic in site and the controller instructs them to "maintain visual separation", the controller needs to keep the two IFR planes apart.
 
mikea said:
I'm Mr. Sceptic, but can't we assume that if aircraft collide and both are not under IFR control, the weather at the time will automatically be VMC?
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I don't think so. They could be operating illegally in IMC or they could be legally operating IFR in Class G airspace.
 
Fearless Tower said:
I'm just curious in the requirement to advise of traffic since I have noticed a significant decline in this service. Unfortunately, unless I am misreading it, what Roncachamp posted seems to refer to aircraft above 10,000. Surely there must be a delineated requirement for traffic below 10k....that's where all the terminal areas are!
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For the situation you described the only requirement to advise of traffic is found in paragraph 5-1-8. MERGING TARGET PROCEDURES. Many controllers issue this advisory to all users regardless of altitude, even though there is no requirement to do so. The "decline in this service" that you observed is probably just due to fewer controllers electing to do it when not required.
 
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roncachamp said:
For the situation you described the only requirement to advise of traffic is found in paragraph 5-1-8. MERGING TARGET PROCEDURES. Many controllers issue this advisory to all users regardless of altitude, even though there is no requirement to do so. The "decline in this service" that you oberved is probably just due to fewer controllers electing to do it when not required.
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Interesting, thanks.
 
How would a controller know when aircraft are in VMC or IMC? How can I have faith in the IR system if their requirements to provide separation service fluctuates like this?
 
Jaybird180 said:
How would a controller know when aircraft are in VMC or IMC? How can I have faith in the IR system if their requirements to provide separation service fluctuates like this?
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Well, ATC separates IFR aircraft regardless of weather conditions. VFR aircraft are separated visually, and they are separated from IMC conditions by cloud clearance requirements.
 
roncachamp said:
Those requirements don't fluctuate like that.
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roncachamp said:
For the situation you described the only requirement to advise of traffic is found in paragraph 5-1-8. MERGING TARGET PROCEDURES. Many controllers issue this advisory to all users regardless of altitude, even though there is no requirement to do so. The "decline in this service" that you observed is probably just due to fewer controllers electing to do it when not required.
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I'm not IR yet, but I am concerned about the potential for collision. Perhaps some study on my part will find the risk unfounded???
 
Jaybird180 said:
I'm not IR yet, but I am concerned about the potential for collision. Perhaps some study on my part will find the risk unfounded???
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There is always a risk. You manage it.

Keep your eyes up looking out the window and scan.

Obey speed limits and cloud clearance requirements. Obey cardinal altitudes. Obey traffic pattern rules if you choose to fly a pattern.

Use flight following often. I've had them miss traffic that I've had to actively avoid, but more often they call out folks that I don't see, and if I can't get a visual I ask for vectors before they get to close.

And keep your eyes out the window and scan.

Fly offset a bit from the centerline of an airway. Be VIGILANT when overflight a VOR on an airway -traffic can converge on that point from all directions (in spite of cardinal altitudes)

Know the system and how it works and how it's built. Then you can use it to enhance safety.

And keep your eyes up looking out the window and scan.
 
Jaybird180 said:
I'm not IR yet, but I am concerned about the potential for collision. Perhaps some study on my part will find the risk unfounded???
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It certainly should. We're talking about merging target procedures; the overlapping of radar targets when minimum vertical separation exists.
 
Jaybird180 said:
How would a controller know when aircraft are in VMC or IMC? How can I have faith in the IR system if their requirements to provide separation service fluctuates like this?
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Most of the time the controller doesn't know - they issue the traffic advisory as they see fit. In those situations you simply tell the controller that you are in IMC. That was basically what happened the night a NORDO 737 almost hit me departing SAN. Controller rather excitedly advised me of the traffic and asked me if I could see him - I had to tell him I was in solid IMC.
 
Fearless Tower said:
Most of the time the controller doesn't know - they issue the traffic advisory as they see fit. In those situations you simply tell the controller that you are in IMC. That was basically what happened the night a NORDO 737 almost hit me departing SAN. Controller rather excitedly advised me of the traffic and asked me if I could see him - I had to tell him I was in solid IMC.
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That's my point about how can I trust? Prior to this discussion, it was my (mistaken) belief that ATC would provide a separation zone around my aircraft while operating IFR.
 
Jaybird180 said:
That's my point about how can I trust? Prior to this discussion, it was my (mistaken) belief that ATC would provide a separation zone around my aircraft while operating IFR.
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What in this discussion caused you to alter that belief?
 
Jaybird180 said:
That's my point about how can I trust? Prior to this discussion, it was my (mistaken) belief that ATC would provide a separation zone around my aircraft while operating IFR.
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They separate IFR traffic from other IFR traffic. If you're IFR, they don't separate you from VFR traffic except in certain airspace (Class B, C, and I believe TRSAs as well but I'm not certain; also not certain about ordinary Class D but my understanding is no). That's why you still need to see and avoid in VMC even if you're IFR.

See JeffDG's post #25 for a very succinct summary.
 
Jaybird180 said:
That's my point about how can I trust? Prior to this discussion, it was my (mistaken) belief that ATC would provide a separation zone around my aircraft while operating IFR.
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Nothing has changed in your belief - the controller is still required to provide separation to a/c in the system. If in VMC, the pilots are additionally required to 'see and avoid'.

The issue I brought up was over the requirement to 'advise' of traffic, not separate and that is what seems left up to the discretion/interpretation of the controller. From digging in the AIM under Pilot/Controller responsibilities, it seems the requirement is to 'issue radar traffic to the maximum extent possible consistent with higher priority duties except in Class A airspace' (AIM 5-5-10). As you can see - Alot of room for interpretation in that one.
 
roncachamp said:
The controller's responsibility for separation between IFR aircraft in VMC is exactly the same as his responsibility between IFR aircraft in IMC.
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And that's a good thing given that most of the time the controllers don't know if the airplanes they're controlling are in IMC or VMC.
 
Jaybird180 said:
Prior to this discussion, it was my (mistaken) belief that ATC would provide a separation zone around my aircraft while operating IFR.
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Also, keep in mind, that in the example I gave it was a bit more challenging for the controller to provide separation when the 737 that was heading right for me missed the handoff and wasn't talking to anyone. The controller DID provide the separation, but he had to canx my approach clearance and vector me around in a 360 in order to do it.
 
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