5-5-7 passing or diverging

[Sassyquatch]

The rule states
" TERMINAL. In accordance with the following criteria, all other approved separation may be discontinued and passing or diverging separation applied when:
a.)...aircraft are on same or crossing courses/assigned radar vectors and one aircraft has crossed the projected course of the other, and the angular difference between their courses/assigned radar vectors is at least 15 degrees.

NOTE-
Two aircraft, both assigned courses and/or radar vectors with an angular difference of at least 15 degrees, is considered a correct application of this paragraph.

b) The tracks are monitored to ensure that the primary targets, beacon control slashes, FUSION target symbols, or full digital terminal system primary and/or beacon target symbols will not touch."

The key issue is "assigned radar vectors". Management is saying aircraft must be established on 15° or more before you apply passing and diverging, but it does not read that way. It reads if you assign a vector that ensures 15° and apply subparagraph b, then you can use passing and diverging prior to the aircraft turning 15° or more.

This is a specific application where I work due to a departure course and arrival course to a satellite airport diverging by 8°. Specifically if an aircraft goes around at the main airport and you have someone on final to the satellite airport.

Management refuses to submit an interpretation request, I've asked at least twice already. Their reasoning is it takes too long to get an answer back. We've been arguing this rule since February. They have email correspondence with a QA/QC person who was once a supervisor here. I've been told it was an "unofficially official interpretation to the rule". Their exact words. The email said the same thing I was told, stating "[QA/QC] opinion is that both aircraft must be established on the headings diverging by 15° or more".

 

[rhombus]

Because that's a whole other set of rules.
Read 5-8-3
And tower is applying other forms of separation ex: visual

5-8-3 sets the rules. 5-5-7 allows you to not have to worry about lateral, vertical, or visual separation after applying those rules

 

[Acquired Taste]

You can assume separation will exist by the time #2 is turned. Assuming separation because of aircraft characteristics is part of our job. There are other factors involved that you're ignoring, like turn rate. A B737 isn't going to go from 270 to 090 in a millisecond and he'll be like 5 miles away from where he first started the turn once established on the 090°.

Now if you used something like a IFR C150 then obviously in these scenarios you will most likely have a loss of separation when putting them on the same exact heading. You've given yourself a watch situation. And why did we start giving examples of assigning a/c the same exact heading? Degree divergence does not involve putting aircraft on the same heading.

The "assigned radar vector"& "course" is something you're trying to define as the exact heading an aircraft is flying. They make it ambiguous on purpose. No where in the book does it state "15° or more from the exact heading of two aircraft when winds are accounted for". Dct FIXES is a 270°. I'll give my second aircraft 285° for divergence regardless of wind. And that is a correct application to this rule. Doesn't matter what either aircraft is tracking or if the wind gives my 2nd 280°. They will NEVER hit and I'm applying the rule as it states. Now, if the winds are just ridiculous and aircraft #2 appears to be more in line with 270° and overtaking #1, you use your best judgement to avoid an unsafe situation.

Do you realize that someone direct to a fix could be tracking 270° on your scope and you could assign a vector to another plane of 285° and with strong winds aloft, they could actually track 265°? It sure would be something to try and explain in court how you were applying divergence when the tracks were actually converging.

Have you never had to correct for wind when vectoring someone to final? If you give them direct to a fix, they fly the course direct to said fix and the plane accounts for the wind. That is not the case when issuing headings.

5-8-3 sets the rules. 5-5-7 allows you to not have to worry about lateral, vertical, or visual separation after applying those rules

Why is ORD tower always holding on to guys?

"Turn right heading 360, remain this frequency for another turn."

It's literally all day, everyday. Don't they know they can just assign the headings off the bat and ship em? Or are they ignorant and inefficient?

 

[Termine]

Are you saying you’re going to wait until that second 737 is established on a 255 heading before switching them to departure?

No, but only because the note at 5-8-3 specifically says you don't have to wait.

“Immediately after departure” is considered to be any turn that provides at least the minimum required divergence that commences no later than 2 miles from the DER.

It's probably good to hold on to them (to continue providing tower visual) at least until you see them "commence" that turn.

 

[MJ]

If you think the language is wrong submit it to the email in 1-1-8

 

[DADDYSbabyBIRD]

5-8-3 sets the rules. 5-5-7 allows you to not have to worry about lateral, vertical, or visual separation after applying those rules

Airport is hard IMC OVC005, tower cannot see airborne departures at all... you're telling me that it's legal to launch successive IFR aircraft 6000 and airborne same runway as long as you issue them headings 15 degrees apart? Would you please let me know what airport uses the rule in such a way? I think TMC would like to know so they can up everyone's departure rates in IMC conditions.

 

[Sassyquatch]

Do you realize that someone direct to a fix could be tracking 270° on your scope and you could assign a vector to another plane of 285° and with strong winds aloft, they could actually track 265°? It sure would be something to try and explain in court how you were applying divergence when the tracks were actually converging.

Have you never had to correct for wind when vectoring someone to final? If you give them direct to a fix, they fly the course direct to said fix and the plane accounts for the wind. That is not the case when issuing headings.

Of course I know this and yes, I've had to correct for wind. Who hasn't? As stated in my previous comment that you quoted in the very last sentence, you use your best judgement if that were to happen.

I've had this discussion with people at my facility. The way I apply the rule is how most people I work with understand the rule. The .65 does not say anything about accounting for the wind.

 

[rhombus]

Airport is hard IMC OVC005, tower cannot see airborne departures at all... you're telling me that it's legal to launch successive IFR aircraft 6000 and airborne same runway as long as you issue them headings 15 degrees apart? Would you please let me know what airport uses the rule in such a way? I think TMC would like to know so they can up everyone's departure rates in IMC conditions.

Of course that’s legal. 5-8-3 says you just need a mile. 6000 feet is a mile so as long as the leader is airborne, you’re gucci. You better make sure the headings you issue comply with 5-5-7 though. If you’re using headings that criss-cross then you need to be using some other form of separation until they’re no factor. But runway heading and then a 15+ degree turn for the next guy is good all day.



OVC005 ceilings should have no impact on departure rates in an of itself. The problem with a lot of airports is that you have to apply 2 increasing to 3 between your arrivals and departures and that can really limit the amount of departures you get out per hour, especially in an arrival push. But if you have minimal arrivals or work at an airport that doesn’t need to use 2 increasing to 3 then you should be able to get out just as many departures in OVC005 as you can with SKC.

 

[Dolan]

That would indeed be a deal if they have less than 15 degrees of divergence between the tracks before they had another form of separation.

Let's make the scenario a little more extreme. Let's say they're still both 737s 250 kts separated by 1,000 feet. #1 heading 090, #2 heading 270 pointed directly at each other. The second they are tail to tail, the controller tells #2 to fly heading 090 and descend through #1's altitude. By your logic, that is a deal because as soon as you assign the heading, you can no longer use passing diverging even though there is a 0% chance they will lose mileage/altitude prior to losing 15 degrees divergence between the tracks.

Just as my hypothetical doesn't instantly give a controller a deal the instant the heading is assigned, your hypothetical doesn't instantly ensure you are legally separated.

Just a quick reply since I'm on break but you're clean until they go from opposite/reciprocal courses to same/crossing without any other form of separation.(I don't think that's physically possible but I'm addressing your argument). If you would have assigned 075 or 105 you'd be clean the whole time since you've assigned a non-conflicting vector unless the targets somehow get back together and satisfied the entire paragraph.

 

[CoffeeIV]

Of course I know this and yes, I've had to correct for wind. Who hasn't? As stated in my previous comment that you quoted in the very last sentence, you use your best judgement if that were to happen.

I've had this discussion with people at my facility. The way I apply the rule is how most people I work with understand the rule. The .65 does not say anything about accounting for the wind.

So the 7110.65 definitely says you have to factor wind and in fact mentions it many times. Call me judgmental but every half decent radar controller I've met factors wind and arguing that you don't have to because youre not instructed to by the book is a weak stance.




Section 6. Vectoring

5−6−2.

METHODS

a. Vector aircraft by specifying:
1. Direction of turn, if appropriate, and magnetic heading to be flown, or
PHRASEOLOGY−
TURN LEFT/RIGHT HEADING (degrees).
FLY HEADING (degrees).
FLY PRESENT HEADING.
DEPART (fix) HEADING (degrees).
2. The number of degrees, in group form, to turn and the direction of turn, or
PHRASEOLOGY−
TURN (number of degrees) DEGREES LEFT/RIGHT.
3.For NO-GYRO procedures, the type of vector, direction of turn, and when to stop turn.
PHRASEOLOGY− THIS WILL BE A NO-GYRO VECTOR, Vectoring 5−6−1 JO 7110.65AA 4/20/23 TURN LEFT/RIGHT. STOP TURN.

b. When initiating a vector, advise the pilot of the purpose, and if appropriate, what to expect when radar navigational guidance is terminated.
PHRASEOLOGY−
VECTOR TO (fix or airway).
VECTOR TO INTERCEPT (name of NAVAID) (specified) RADIAL.
VECTOR FOR SPACING. (if appropriate) EXPECT DIRECT (NAVAID, waypoint, fix)
VECTOR TO FINAL APPROACH COURSE, or if the pilot does not have knowledge of the type of approach, VECTOR TO (approach name) FINAL APPROACH COURSE.

NOTE− Determine optimum routing based on factors such as wind, weather, traffic, pilot requests, noise abatement, adjacent sector requirement, and letters of agreement.

 

[SquawkHijack]

That seems like over controlling. Let’s say you’re using Runway 27. Two 737s. First 737 is given runway heading. You get 6000 and airborne, second 737 is given a 255 heading and cleared for takeoff. Are you saying you’re going to wait until that second 737 is established on a 255 heading before switching them to departure?

It doesn’t matter if there’s only 2 miles of separation between those 737s when the second one rotates. You assigned 15 degrees of divergence between them and can switch the second 737 to departure as soon as you want.

Negative, if you switch a second aircraft to departure and have 15 degrees with LESS than one mile in trail of the first, you just handed departure a bust that will ultimately fall on you. We are talking about passing or diverging which involves 15 to 135 degrees divergence and target resolution. You’re referencing successive, same runway departures. There are different minima between the two.

Yeah this is what I was thinking cause without it how are places like ORD launching guys that fast lol

ORD is also authorized to use other forms of separation. For example, if 2 aircraft are executing separate, diverging published SIDS, that only need 10 or sometimes even 7 degrees divergence and 1 mile in trail.

Kinda apples and oranges in respect to other facilities. Especially when what you’re referencing is successive, same runway departures. Not passing or diverging. They have different minima.

 

[rhombus]

Negative, if you switch a second aircraft to departure and have 15 degrees with LESS than one mile in trail of the first, you just handed departure a bust that will ultimately fall on you. We are talking about passing or diverging which involves 15 to 135 degrees divergence and target resolution. You’re referencing successive, same runway departures. There are different minima between the two.

Never in the scenario I laid out will you ever end up with less than a mile. The point I was making was that you don’t have to have the standard 3 miles of separation before they’re switched to departure because of the 15 degrees of divergence assigned.

 

[SquawkHijack]

Never in the scenario I laid out will you ever end up with less than a mile. The point I was making was that you don’t have to have the standard 3 miles of separation before they’re switched to departure because of the 15 degrees of divergence assigned.

I understand the point you’re making, but I’m countering your point by simply saying that you’re comparing two different kinds of separation laid out in two different places of the 7110. This thread is regarding passing or diverging, you are referencing same runway separation for successive departures. The difference lies between a mile and target resolution.

And you can absolutely lose 1 mile between two similar-type departures. I’ve seen it actually between two 737s. The leader was a Delta 738 full of people and bags that hit a gust front at ~500AGL, the follower was an empty KII (cargo) 738 that was cleared and rolled with 6000 & airborne. Another mile upwind and QA deemed a loss on the tower at 0.8NM before departure could get a better turn and climb for the leader.