Major Airspace Math

[Matthew Kramer]

Want to be clear here that the way to calculate “33%” for a division and “25%” for a sub-division is by taking all the controllable airports (i.e. with a control tower) plus all TRACON areas (combined and split). 

 

Airports are designated as major or minor (or restricted) and the overlying airspace is thusly also major but doesn’t count against the total.

 

Is that correct? For example, KLAS is a major airport, and the L30 TRACON above it equals “2” but only KLAS is “major” and thus there is only “1” major.

 

KSAN, KMYF, KSDM, KCRQ, KSEE etc are 5+, SOCAL SAN is 1, and the remaining SOCALs are 5 so that’s “1” major airport with major airspace on top of it for a total of 11+?

Edited July 21, 2021 at 04:56 AM by Matthew Kramer

[Harry Sugden]

Also, if a bandbox of 2 or 4 main sectors are restricted, but the individual sectors are not, does that count towards the total...? Confusing!

[Phil Dowling]

Ohhh Harry.  It's only confusing when you try to overcomplicate it 😉 😛 LOLOL. J/K 😉

So...to take a couple of examples from Matthew.

8 hours ago, Matthew Kramer said:

For example, KLAS is a major airport, and the L30 TRACON above it equals “2” but only KLAS is “major” and thus there is only “1” major.

So in this instance.  KLAS is the major.  The L30 Tracon is not considered a major airspace, so would not count in the total.  HOWEVER, in order to control the Tracon, as it contains a major airport/airspace, and due to top down.  The controller would need to hold the major certification for KLAS.  Make sense?

8 hours ago, Matthew Kramer said:

KSAN, KMYF, KSDM, KCRQ, KSEE etc are 5+, SOCAL SAN is 1, and the remaining SOCALs are 5 so that’s “1” major airport with major airspace on top of it for a total of 11+?

In this example.  What is the major airspace/airport.  If the Major Airspace is considered to be SOCAL.  That it is major does not translate down to all the individual fields.  It simply applies to the SOCAL airspace.  The fields would remain as either Minor/Restricted or however they are defined.  So a TWR controller could validly control at KSAN but would need the rating AND major endorsement in order to control SOCAL.

 

Hopefully that helps a little.

Phil

[Alex Ying]

I have many concerns similar to Matthew regarding how to count facilities. Like ZLA, ZNY has extremely complex airspace and we have 4 Class B airports in close proximity with numerous underlying fields. Combined with the current proposal to dis-allow competency checks on sub-division transfers (VATUSA ZXX -> ZNY), we are very concerned about transfer controller quality at these underlying fields.

1. Is en-route excluded from the 25% count? Based on my early reading of the policy, it looks like all en-route is automatically Restricted and can be upgrade to Major and also doesn't count as a terminal or aerodrome facility so my guess is no. Is this correct?
2. How are large / consolidated TRACONs counted? Is NY TRACON (N90) counted as 1 terminal facility? There are 5 "areas" in N90 which line up with the RW division into areas (LGA, JFK, ISP, EWR, LIB). Are each of those counted as a facility or is the entire TRACON 1 facility?
3. How are up-down facilities counted? Philadelphia Approach/Departure is the same facility as Philadelphia ATCT and IRL controllers work both the radar room and the cab. Do we count this as 1 or 2 facilities for GCAP purposes?

We at ZNY are very concerned about situations where a brand-new VATUSA transfer comes in, and because we cannot assign Restricted status to say TEB or FRG or ISP due to the limitation on the number of Restricted facilities, logs on without doing any competency check or familiarity training and provides bad service. It is true that TEB does not require as much training as its neighbor EWR, but it still requires learning some knowledge about how New York TRACON is set up and the basics of the airspace which means it should fall into Restricted status. We have 17 towered airports the sit below N90.

There are 2 ways to resolve this issue. One is to increase the number of allowable Restricted airports which I think this is the wrong approach. Instead, we should allow competency checks on sub-Division transfers so that we can keep those airports in minor status instead of having to upgrade them to Restricted.

[Matthew Bartels]

The language here needs to be better flushed out.

The intent is that you must have significantly less airspace that requires restrictions than airspace that requires restrictions.

Enroute does not count towards the number. It’s controllable airports and terminal facilities.

The thought with the consolidated TRACONS is that each area counts as one. So JFK, LGA,EWR, ISP,LIB are all one. Same goes for the airports. 

The idea is that if you have 8 towered airports in your subdivision then you can designate 2 of them as restricted. If one of those is designated as a major then you can only designate 1 airport as a restricted.  Where I’m now a bit confused is the tracons. The original thought was that your total controllable airspace is what controlled the percentage. So in the above example let’s say that there are only 4 TRACONS in the airspace. Your total controllable facilities is 12. This way you could designate up to 3 general airspaces as Restricted and/or Major. If the airport is major though then the tracon would be major. So this would burn 2 slots. But if all 8 had a terminal facility, then you get 4. It would be then up to the local facility to decide how to apply that. Do you put the restriction on the TRACON, do you put it on the tower? Do you put it on Both and essentially have just 2 airports with restrictions.

I’ll need to think about how to get this worded better. 

Concerning the intradivsiional comp check. It’s understandably a concern but the truth is that a controller within the same division is to be a the same standard if awarded a rating. (Yes, I know that’s not how it really is today) However this is a practice that has been abused far too long in keeping visitors and transfers off scopes and one that will be ending. Other avenues are provided for controllers that refuse to Improve.

 

 

[Ben Lindsey]

12 minutes ago, Matthew Bartels said:

Concerning the intradivsiional comp check. It’s understandably a concern but the truth is that a controller within the same division is to be a the same standard if awarded a rating. (Yes, I know that’s not how it really is today) However this is a practice that has been abused far too long in keeping visitors and transfers off scopes and one that will be ending. Other avenues are provided for controllers that refuse to Improve.

I’d like to think that I’m at least an okay controller that meets all the competencies expected of a C1. That doesn’t mean I’d be capable of jumping right in to an airport in N90, even after a thorough review of the SOP. I might be okay, but it’s not fair for “maybe” to be the standard that controllers come to expect from one another of airspace understanding. 

[Matthew Bartels]

In practice, N90 is restricted at the minimum so its somewhat of a moot point. That requires extra training. However as a C1, would you not be able to work a place like AVP with a good read of an SOP and LOA?

[Matthew Kramer]

I've addressed the VC/Transfer comp checks in a different thread, but the math on this is still clouded so I'd like to stay on topic. The current "top-down" system extends "major" designation to overlying airspace. LAX_CTR is "Major" by virtue of having 3 "major airports" within it. We control the whole ARTCC and thus a controller needs major endorsements to work it (in addition to their C1). Likewise, overlying approach facilities need major endorsements (and S3) because the airports are major. However, because we have "Combined" TRACONs, there are several terminal facilities that can be worked together that overly a major airport and are thus major, but worked as an individual sector may be considered "minor."

Moreover, SOCAL is actually 6 (or 7, depending on how you count) different TRACONs. The wording as-is doesn't imply that you eat up "2" slots with a designation. You can't control LAX_APP without controlling LAX. 

[Thimo Koolen]

30 minutes ago, Matthew Bartels said:

The thought with the consolidated TRACONS is that each area counts as one. So JFK, LGA,EWR, ISP,LIB are all one. Same goes for the airports.

@Matthew Bartels I have a question regarding this. See this chart: https://www.lvnl.nl/eaip/2021-06-03-AIRAC/graphics/eAIP/EH-ENR-6-2-1.pdf

 

On Vatsim, Schiphol (EHAM) approach covers Lelystad (EHLE) and Rotterdam (EHRD). EHAM is major airfield, EHLE and EHRD are not. However, the EHRD + EHLE TMA's are part of/bordering the EHAM TMAs. Would this be concidered as consolidated TMA's, thus already requiring major endorsement for EHRD + EHLE APP positions (not the airfield positions)? We (Training Department) are probably thinking of making EHRD APP + EHLE APP restricted (because it has a huge impact on EHAM APP operations, this should be instantly clear from the chart above), but if these APP sectors are automatically considered to require a major endorsement, then that would be even better.

[Alex Ying]

AVP, ABE, BGM, etc. is not where we're concerned, those would all remain as minors, there's no point restricting them. For sake of discussion, let's assume all N90 areas, and KJFK, KLGA, KEWR (the Class B airports) stay major. Our concern is an underlying airport like TEB. Specific things like how to handle the Skyline route, or preferred routes (where do I find these? What do the different restrictions in the database mean?), or even who is controlling airspace above you are non-trivial even with a thorough read of the SOP and LOAs (of which there are many). I think a fundamental philosophical difference we're seeing here is that we want to be proactive in providing training and assessing competency, rather than being reactive letting nominally rated (but maybe out-of-practice or lapsed currency which I will leave the definition to another thread) control, providing bad service and and getting bad feedback, and then trying to do something remedial.

Back on topic, I think the crux of the issue that Matthew also just pointed out is that this policy may be too general and not account for the vast difference in how airspace is designed across the world. If every N90 area has to be separately counted, and the PHL radar room separately from the PHL cab, that's already 10 major facilities in ZNY which eats up our entire allocation of restricted facilities with Major facilities alone, leaving us no flexibility to mark an airport restricted like TEB (which legitimately could use a Restricted label, independent of any of the competency check stuff I brought up earlier).

[Matthew Wurzbach]

I get the overall concept here. We want to open controlling up to people and give them the opportunity to control in settings where it won't adversely affect large volumes of traffic (majors and restricted facilities). I think this policy is too loosely defined and too strict. I would rewrite it:

"4.02 Designation of Restricted Airspace

4.02(a)A sub-division may designate not more than 75% of all controllable aerodromes and terminal facilities within that sub-division as any combination of Restricted Airspace or Major Airspace. Not more than 50% of all controllable aerodromes may be designated as Major Airspace."

Delete 4.02(b) and all of 4.03.

This leaves, at a minimum 25% of facilities controllable for controllers who hold a minor cert only, which is plenty of options for someone who wants to put in only minimal effort and control minimal traffic levels. I think most sub-divisions will be less restrictive than this. I know my sub-division reviewed this policy and the initial reaction was we could get by with about 40-50% of fields designated as restricted and/or major in combination.

[Andre Almeida]

I'd also like to receive an example of this working, please. This was just being talked about in the Discord, and to help me visualize everything I created a fictitious example, which led me to believe that this might not work as hoped.

Quote

A fictitious division constituted of 3 sub-divisions:

Sub-division A: 15 airports
Sub-division B: 9 airports
Sub-division C : 6 airports

Division Total: 30 airports

33% can be major, so up to 10.

However, each sub-division can have only up to 25% of their airports as major or restricted

Maximum major/restricted in each sub-division:
Sub-division A: 3,75 (does this round up to 4 or down to 3? I'll assume for now everything rounding up, regardless of the decimals, so I don't make this impossible due to rounding)
Sub-division B: 2,25 ~= 3
Sub-division C : 1,5 ~= 2

2 + 3 + 4 = 9

So the maximum amount of majors and restricted of all sub-divisions together is lower then the amount of majors the division can have. And that is with everything rounding up. If everything were to round down the sub-divisions could only use in total 6 majors, even though the division can have 10. And all of that would leave no room whatsoever for restricted airports.

 

Would it be possible to receive an example of the 33% Major in a Division and 25% Major+Restricted in a Sub-Division? I can't visualize how this would work with these percentages.

And how will the rounding work? Will we use the standard convention of x.5 - x.999(9) rounds up, and everything below rounds down, or will everything round up, or everything round down? This rounding detail will make a difference to sub-divisions who have few airports.
 

Edited July 22, 2021 at 09:36 AM by Andre Almeida

[Erik Quinn]

1 hour ago, Andre Almeida said:

Would it be possible to receive an example of the 33% Major in a Division and 25% Major+Restricted in a Sub-Division? I can't visualize how this would work with these percentages.

I'm glad somebody else noticed this, because no, it is definitionally impossible to get any more than 25% total (division level) if each portion of the whole (subdivision) is restricted to 25%.

You got close by rounding up, but I am certain they will not allow rounding up like that-- if we at the subdivision level are limited to 25%, then 15 airports x 25% = 3.75 = 3 airports (20%). To round up to 4 airports would be 26.7%, in excess of our allowance.

Unless they're just really bad at basic math, all I can assume is that they meant subdivisions 33% restricted+major, and no more than 25% of a division's airports can be major (in other words, sometimes you'll have to settle for restricted status instead of major).

[Rick Rump]

4 hours ago, Erik Quinn said:

all I can assume is that they meant subdivisions 33% restricted+major, and no more than 25% of a division's airports can be major

It is confusing, technically the 4.03(b) exists for Divisions without Sub-Divisions, it really needs to be clarified and it was in a previous draft.

[Matthew Bartels]

It needs to be 25% and 25% if you want to play it that way. The point being that giving a division the power to designate a major, of which we want very very few of them, needs to be met with a hard restriction of how many is too many.  The thought was that in a division that has 100 towers. only 33 of them could be designated as major. Now if that division has sub divisions. those 33 towers get spread out into those sub-divisions. The sub division then has the power to designate restricted airspace. So lets say that sub-division A has 15 towers and 2 of those were designated major. So if no more than 25% of airports in a sub division can be designated as major or restricted. That means you have 3 that can be restricted in some way. Since 25% of 15 is 3 and change. You can only have 3 total. Your two majors eat up 2. You can designate 1 additional airport as restricted.

[Erik Quinn]

4 hours ago, Matthew Bartels said:

It needs to be 25% and 25% if you want to play it that way. The point being that giving a division the power to designate a major, of which we want very very few of them, needs to be met with a hard restriction of how many is too many.  The thought was that in a division that has 100 towers. only 33 of them could be designated as major. Now if that division has sub divisions. those 33 towers get spread out into those sub-divisions. The sub division then has the power to designate restricted airspace. So lets say that sub-division A has 15 towers and 2 of those were designated major. So if no more than 25% of airports in a sub division can be designated as major or restricted. That means you have 3 that can be restricted in some way. Since 25% of 15 is 3 and change. You can only have 3 total. Your two majors eat up 2. You can designate 1 additional airport as restricted.

Well this answers my question-- yes, this stems from errors in basic math. Let's review your example:

Division (having two subdivisions): 100 towers, allowed 33 majors (33%)
Subdivision A: 50 towers, major+restricted = up to 12 towers (25% --> 12.5 airports, rounded down)
Subdivision B: 50 towers, major+restricted = up to 12 towers (25% --> 12.5 airports, rounded down)

Together, subdivisions A and B can only have 24 major fields. Their parent division is allowed "up to 33", but are "full" once they reach 24 airports (24%). The notion that "those 33 towers get spread out into those sub-divisions" is mathematically impossible... There is no scenario where subdivisions restricted to 25% can add up to a total of 33%. It, quite literally, does not add up.

[Artur Vasiljev]

Hey!

I have a little proposal for this part of the policy. 4.05 says:

Quote

Exemptions to the limits prescribed in 4.02(b) and 4.03(b) may be approved in extraordinary circumstances by the Regional Vice President.

There are quite many places with not that many towered airfields. There are even some that have so little that they won't even be able to designate 1 airport as major/restricted minor. Could we make it so each division/subdivision always has the right to designate 1 airport and/or airspace as major/restricted minor regardless of the numbers, just to we don't have to make a request to the regional VP for each of these cases. That largely would solve the problem for such places as VATSSA, the Netherlands, Latvia, Estonia, UAE, etc.

What do you think? @Matthew Bartels

[Thimo Koolen]

The maths aren't fair for smaller countries anyway, so you're correct on that. I would suggest something like "a maximum of 3 airports or xx% of controllable aerodromes / TMAs, whichever is larger" to make it more fair for those smaller countries.

 

Also: I've heard the calculation is as follows: all controllable aerodrome sectors (irrelevant are the amount of DEL/GND/TWR positions, it's the aeorodromes that count) + all controllable TMA's for these airports. And then 25% of that. However, an aerodrome that is considered major, means that the relevant TMA/APP sector is automatically major as well (due to Vatsim's top-down principle). WHY, oh WHY does the TMA sector also count towards the 25% limit here?

[Greg Barber]

On 7/31/2021 at 7:58 AM, Artur Vasiljev said:

Hey!

I have a little proposal for this part of the policy. 4.05 says:

There are quite many places with not that many towered airfields. There are even some that have so little that they won't even be able to designate 1 airport as major/restricted minor. Could we make it so each division/subdivision always has the right to designate 1 airport and/or airspace as major/restricted minor regardless of the numbers, just to we don't have to make a request to the regional VP for each of these cases. That largely would solve the problem for such places as VATSSA, the Netherlands, Latvia, Estonia, UAE, etc.

What do you think? @Matthew Bartels

This is exactly why the Regional VP can over-rule this clause and grant permission for a major in a facility that cannot satisfy this requirement.  An example is Hong Kong. 

[Artur Vasiljev]

9 hours ago, Greg Barber said:

This is exactly why the Regional VP can over-rule this clause and grant permission for a major in a facility that cannot satisfy this requirement.  An example is Hong Kong. 

My point is that making a request to the VP for every airport that we need to designate as major/restricted minor in a place with not enough airports would be annoying both for you and the VP. That is why the proposal of '3 or xx%, whichever is larger' makes sense. It reduces bureaucracy and generally makes it easier for both sides.

[Simon Irvine]

On 8/1/2021 at 11:13 AM, Artur Vasiljev said:

My point is that making a request to the VP for every airport that we need to designate as major/restricted minor in a place with not enough airports would be annoying both for you and the VP. That is why the proposal of '3 or xx%, whichever is larger' makes sense. It reduces bureaucracy and generally makes it easier for both sides.

I don't envisage this being a lot of airports Artur.  I have already had conversations with David Kirchner in EUD regarding which airports will need an override for the policy.

[Artur Vasiljev]

1 hour ago, Simon Irvine said:

I don't envisage this being a lot of airports Artur.  I have already had conversations with David Kirchner in EUD regarding which airports will need an override for the policy.

Yeah, heard of that too. Well, if you're ok with it then why wouldn't I be. Thanks!

Edited August 2, 2021 at 08:16 PM by Artur Vasiljev