“Maintain Visual Separation”

[JNev]

Other than wake turbulence application, what use does this phrase have in ATC? I repeatedly hear coworkers and NCT controllers use it and I don’t really understand saying it to a VFR pilot after they have traffic in sight. They’re flying VFR so legally they always have to maintain visual separation and also they should if they want to not collide with other A/C. Isn’t it just wasted verbiage and redundant?

 

[Cmsgthokage]

Other than wake turbulence application, what use does this phrase have in ATC? I repeatedly hear coworkers and NCT controllers use it and I don’t really understand saying it to a VFR pilot after they have traffic in sight. They’re flying VFR so legally they always have to maintain visual separation and also they should if they want to not collide with other A/C. Isn’t it just wasted verbiage and redundant?

It’s used a lot in approach too. Let’s say you have 2 IFR aircraft and you need to descend/climb one and if you do you’ll lose your 1000ft/3mi. When one gets the other in sight and you use visual separation between them as long as you have the appropriate IFR sep before and after the application of vis sep.

Another example is visual approaches #2 has #1 in sight then they can follow them to land.

Edit: as far as the NCT controllers using it with VFR a/c I assume it’s just good practice.

 

[JNev]

Okay cool that makes sense from an approach perspective then

 

[Shikaka]

Like Cmsgthokage said, though its common on approach. Our airport has centerline 700' apart. Vis Sep is useful for overtakes to the parallel runway. Same thing with smaller A/C on the go around, tower can issue a visual approach, so a small IFR jet on a visual approach can go into the pattern and have visual separation with traffic on final, #2 to follow/maintain visual and cleared to whichever runway.

So depending on what typical traffic is for you, it could be used more often other than wake turb.

 

[Stinger]

From an approach standpoint, it's mostly redundant telling a vfr aircraft to maintain visual separation (excluding wake turbulence.)
However, the 7110 says that aircraft in some airspace categories need to be separated with either 500 feet vertical, target resolution, or visual separation. For me... I'll never tell a vfr Cessna to maintain visual from a large or smaller inside a class C airspace. He's doing it automatically by vfr rules.

 

[JNev]

I notice it when they're giving traffic calls to guys on a right base for 28R about a guy on a straight in on 28L, two successive VFR departures going similar directions, and VFR guys following other VFRs and IFRs on the same RWY

 

[Shikaka]

I notice it when they're giving traffic calls to guys on a right base for 28R about a guy on a straight in on 28L, two successive VFR departures going similar directions, and VFR guys following other VFRs and IFRs on the same RWY

VFR to VFR "maintain visual" is pointless unless there is wake turbulence. They're see and avoid by VFR rules.

 

[Phillyman2633]

Every time a tower controller tells a VFR to "maintain visual separation" with another VFR, a puppy gets punched in the face. Or tells a VFR pilot to maintain visual separation with an IFR for that matter.

What the fuck is the alternative? Tower didnt tell me to maintain sep with that traffic, guess I'll just die now.

 

[CF]

People do this where I work and it's annoying but I'm not gonna die on the hill trying to convince them to change.

 

[JNev]

They think they’re protecting themselves if the VFRs crash lol

 

[DankVectorz]

It’s as annoying and redundant as “squawk 1234 and ident”

 

[CaptainObvious]

Never personally seen anyone do it but ?‍♂️

 

[Bob44zw]

Um - when I fiest heard the phrase it was a magic set of words that the pilot had to initiate - controllers could not prompt us - kinda like a special VFR clearance. If you didn't know the secret words, you could wait three minutes for the King Air wake to settle down.

I was outraged - how could I possibly catch that King Air? Answer - the words do not mean what they say - they mean "waive the wake turbulence."

"Line up and wait" is the same - it does not mean line up, it means "taxi into position on the runway and hold." Our patient controllers are still explaining it, and it has been a decade!

Now all we have to say is "King Air in sight" and the tower controller says the magic words that do not mean visually separate yourself from the King Air. We learn these things and deal with them.

New guy - just escaped from Stuckmic - those folks were a big help before the forum got revamped.

 

[joker432]

Um - when I fiest heard the phrase it was a magic set of words that the pilot had to initiate - controllers could not prompt us - kinda like a special VFR clearance. If you didn't know the secret words, you could wait three minutes for the King Air wake to settle down.

I was outraged - how could I possibly catch that King Air? Answer - the words do not mean what they say - they mean "waive the wake turbulence."

"Line up and wait" is the same - it does not mean line up, it means "taxi into position on the runway and hold." Our patient controllers are still explaining it, and it has been a decade!

Now all we have to say is "King Air in sight" and the tower controller says the magic words that do not mean visually separate yourself from the King Air. We learn these things and deal with them.

New guy - just escaped from Stuckmic - those folks were a big help before the forum got revamped.

If you think it means “waive the wake turbulence” then you are mistaken. When you tell us you have the King Air in sight and you are maintaining visual, you should be plotting the right amount of spacing you feel comfortable with to avoid the wake turbulence. Additionally if you are watching the King Air depart then you should see it’s point of rotation which is where the wake turbulence begins. Then you can better avoid it.

 

[Bob44zw]

Thanks. My understanding was that it relieved the controller of that responsibility. It, as far as I can tell, is always the PICs responsibility to avoid wake turbulence, even before the magic words are spoken. But your understanding makes the words even less of a match with what is actually happening.

 

[colombia_atc]

I use visual separation a lot working approach (arrival). When vectoring to follow from the downwind or base, and particularly when filling a gap on final, it's easy to lose separation technically, even though the airplane will be in the gap once you're done. It's also handy when you're running visual parallel approaches but the airplanes aren't seeing the airport very far out (say, less than 10 miles). You need one airplane cleared for the visual approach or visual separation. Working at LAX during an arrival push, working arrivals to all 4 runways simultaneously... you will say "maintain visual" and "follow" (which is also visual separation) more times than you can count.

As for VFR aircraft, it depends on the airspace. Yes, a controller can definitely have a separation error with a VFR aircraft in B or C airspace, or in a TRSA. Visual separation is neither assumed nor automatic, even for VFR aircraft, as far as the controller is concerned. In that airspace where VFR aircraft must be separated, the controller must apply the separation standards or instruct the aircraft to "maintain visual separation," even if it's a VFR aircraft.

Per the .65, in the Visual Separation section (7-2-1): Separation requirements also apply to VFR aircraft when IFR, Class B, Class C or TRSA separation services are required.

Visual separation for VFR aircraft is also specifically mentioned in the sections for TRSA, B, and C airspace.

There is a difference between see-and-avoid and positive separation. VFR aircraft in those classes of airspace are guaranteed ATC radar separation (in most cases) so the "maintain visual separation" is supposed to impress on the pilot that ATC is relieving itself of that obligation.

(sorry for not completing this thought earlier... I realize the original question was about VFR aircraft)

 

[Phillyman2633]

Thanks. My understanding was that it relieved the controller of that responsibility. It, as far as I can tell, is always the PICs responsibility to avoid wake turbulence, even before the magic words are spoken. But your understanding makes the words even less of a match with what is actually happening.

"Waive wake turbulence" and "maintain visual sep" are 2 separate things that I think you've melted into one concept.

"Waive wake turbulence" is something you say if you're trying to depart behind a heavier aircraft (not including heavies, which cannot be waived) so if you're trying to depart behind a B737 or a A320, you can say the magic words and get rolling. Also, if you're departing from an intersection more than 500 feet down the runway from where a larger aircraft started their takeoff roll, you have to wait 3 minutes unless you use those magic 3 words. There are different weight categories, but I think even a B350 (Super King Air) would cause you a 3 minute wait if you're trying to depart from an intersection after they roll full length. You can say "Waive wake turbulence," however, controllers cannot solicit (same with a contact approach).

"Maintain visual separation" is what you use when approach fucks up speed control on final. If I have an A320 doing 200kts and approach dumps them 5.5nm in trail with an A340 doing 140kts, in about 30 seconds I'm going to lose my required 5nm of separation so if it's a nice clear day, I can tell the A320 to maintain visual sep with the heavy. I am allowed to give him this instruction, there is nothing withholding me from giving the pilot this clearance (as there is with the previous scenario where I cannot solicit). If the pilot cannot or doesn't want to maintain his own visual separation with the heavy, he can say Unable and I'll have to take him off the approach if he cant slow in time. There are plenty of other scenarios in which you would use Maintain Visual Separation, but that is the most common one in the tower environment.

As you mentioned, as a VFR pilot you are always supposed to maintain your own separation with any traffic we issue you (and you report in sight). "Maintain visual separation" is an IFR-to-IFR function, so if you're flying around VFR and a controller tells you to maintain visual separation with some other traffic, then they dont have an understanding of the rule.

 

[Shikaka]

As you mentioned, as a VFR pilot you are always supposed to maintain your own separation with any traffic we issue you (and you report in sight). "Maintain visual separation" is an IFR-to-IFR function, so if you're flying around VFR and a controller tells you to maintain visual separation with some other traffic, then they dont have an understanding of the rule.

And another example of depends on where you go, our parallels are 700' centerline to centerline and we're wake recat. So the VFR C172 on the downwind is going to get a "maintain visual caution wake turbulence" with the IFR A306 short final since we're required to treat our 2 runways as 1 for wake turbulence at times.

 

[MJ]

There's multiple topics going on in this thread and I think it's becoming intertwined. To clarify: OP was talking about the meaningless instruction some people say when issuing traffic to a VFR a/c.

Bob's talking about being told to maintain visual in the pattern, where wake from a previous departure comes into play. Which is effectively "waiving wake turbulence". He's correct, and the application is correct as well. The FAA implemented/withdrew/re-implemented this rule a few years ago with lots of headache over the usage of "maintain visual". I guess they couldn't think of another phrase and just reused that one.

Some others are referencing the actual usage for IFR A/C which philly explained pretty well above.

 

[colombia_atc]

"Maintain visual separation" is an IFR-to-IFR function, so if you're flying around VFR and a controller tells you to maintain visual separation with some other traffic, then they dont have an understanding of the rule.

This is not always true. Visual separation procedures (i.e. "maintain visual separation") for VFR aircraft do apply in B, C, and TRSA airspace. This is specifically addressed a few times in the appropriate sections of chapter 7. Even student and VFR-only pilots -- particularly those who routinely fly to/from airports in B, C, or TRSA airspace -- are supposed to be familiar with this procedure.