How are ARTCC boundaries determined?

Discussion in 'Flight Following' started by Ryanb, Mar 10, 2019.

  1. Ryanb

    Ryanb Final Approach PoA Supporter

    Joined:
    Jul 21, 2010
    Messages:
    9,091
    Location:
    Tennessee
    Display Name:

    Display name:
    Ryan
    Some are much larger than others and have interesting boundary lines. How do they determine these boundaries? Seems like several Centers could be consolidated.

    91123DAF-C2D1-434C-A070-819F7693768F.jpeg
     
  2. murphey

    murphey Final Approach PoA Supporter

    Joined:
    Aug 21, 2008
    Messages:
    8,342
    Location:
    Colorado
    Display Name:

    Display name:
    murphey
    I have no clue but looking at the map, I’d guess commercial aircraft density for takeoffs and landings. Note that each one has 1 or N Class B or very busy Class C airports. except for jackson, but that’s on the borderline for Miami with 4.
     
    Last edited: Mar 10, 2019
  3. Let'sgoflying!

    Let'sgoflying! Touchdown! Greaser! PoA Supporter

    Joined:
    Feb 23, 2005
    Messages:
    16,541
    Location:
    west Texas
    Display Name:

    Display name:
    Dave Taylor
    I bet its going to include available resources vs demands on the system.
     
  4. Ryanb

    Ryanb Final Approach PoA Supporter

    Joined:
    Jul 21, 2010
    Messages:
    9,091
    Location:
    Tennessee
    Display Name:

    Display name:
    Ryan
    Interesting observation, I didn’t catch that. To me, it would seem like Jacksonville could consolidate with Atlanta or Miami and Ft Worth could consolidate with Houston.
     
  5. sarangan

    sarangan Line Up and Wait

    Joined:
    Jun 7, 2008
    Messages:
    514
    Location:
    Dayton, OH
    Display Name:

    Display name:
    Andrew Sarangan, CFII
    But ZJX also covers a heavily traveled north-south corridor.

    ZJX.png
     
  6. John Collins

    John Collins Pattern Altitude

    Joined:
    Feb 29, 2008
    Messages:
    2,213
    Location:
    Charlotte, NC
    Display Name:

    Display name:
    John
    There are actually multiple boundaries for the various centers. The published ones are the ones charted on the Low IFR enroute charts and the High IFR enroute charts. There are many other boundaries and they change infrequently, but more often. The boundaries are vertically stratified and based on agreements between centers and TRACONs. For filing flightplans, the surface boundary is the most important, because it is where the flightplan needs to be routed to in order for it to be accepted into the ERAM system. The surface boundaries were just published at my request. Here are the surface boundaries and there are significant differences between them and the published boundaries. These are based on agreements between the players and don't change often, but when a new metroplex is put into effect or the airspace needs a major improvement, these boundaries are affected.
     

    Attached Files:

    flyingcheesehead likes this.
  7. John Collins

    John Collins Pattern Altitude

    Joined:
    Feb 29, 2008
    Messages:
    2,213
    Location:
    Charlotte, NC
    Display Name:

    Display name:
    John
    Here is an example of a surface boundary that is much different than the charted boundary in the Tampa - Orlando region. The magenta is the surface boundary and the blue course line is an overlay of the Miami charted boundary.
     

    Attached Files:

  8. luvflyin

    luvflyin Final Approach

    Joined:
    May 8, 2015
    Messages:
    5,960
    Location:
    Vancouver, WA
    Display Name:

    Display name:
    Luvflyin
    That could require building new Centers. There’s only so much room for Scopes and people in any given building. May happen someday, who knows. There used to be a Great Falls Center. I’m pretty sure it was when they built a new one in Salt Lake is when they took over Great Fall’s Sky. Same thing happened to Phoenix Center. LA and Albuquerque got pieces of it. Maybe Denver to.
     
  9. luvflyin

    luvflyin Final Approach

    Joined:
    May 8, 2015
    Messages:
    5,960
    Location:
    Vancouver, WA
    Display Name:

    Display name:
    Luvflyin
    That looks like Forflight. How did you get that to come up?
     
  10. John Collins

    John Collins Pattern Altitude

    Joined:
    Feb 29, 2008
    Messages:
    2,213
    Location:
    Charlotte, NC
    Display Name:

    Display name:
    John
    An associate generated a map layer to reflect the surface boundaries as user content, and I installed it on my ForeFlight. As far as the charted boundary on the map for comparison, I just loaded the IFR Low altitude chart and put in a route that overlaid the charted boundaries.

    I just attached the zip file to an email and sent it to my iPad or iPhone that has FF installed. Tap on the zip attachment and use the send to icon. It will then display options for the send-to, I chose "Open In", then on the middle line, I scrolled to the "Copy to ForeFlight" icon and tapped it. Then it opens FF and you accept it. Tap the layers and select the new one at the bottom of the RH layers. It should read as ERAM A...31-Jan-19.
     

    Attached Files:

  11. John Collins

    John Collins Pattern Altitude

    Joined:
    Feb 29, 2008
    Messages:
    2,213
    Location:
    Charlotte, NC
    Display Name:

    Display name:
    John
    Routing of flightplans needs to be to the correct center. This is the center you would call to locate your flightplan if you knew the center telephone number. For flightplans that depart from airports, the center the flightplan needs to be routed to is always known as it is published in the FAA database NASR, so flightplans will go to the right center. But, if you file from a point that is not an airport, such as a VOR, a named fix, a latitude-longitude, or a fix-radial-distance, the surface boundary is important for the filing program to know so it can route the flightplan accordingly. If it goes to the wrong center, it is simply discarded by the center who in turn sends a rejection message back to the filing system. In some filing systems, this simply results in ATC not being able to find the flightplan when the pilot calls for their clearance. Usually this only affects IFR pickups after a VFR departure and pickup the flightplan when airborne, down the road. It would also potentially affect departures from farmer's fields, or a seaplane or amphib lake departure, or an accident scene by a helicopter.
     
  12. mcheathe

    mcheathe Filing Flight Plan

    Joined:
    Nov 29, 2012
    Messages:
    22
    Location:
    Vancouver,WA
    Display Name:

    Display name:
    Mike C
    After WWII, when commercial airlines were growing by leaps and bounds their main customer were business flyers, traveling from a major business to another major business center. Air carriers and military made up 95% of the IFR traffic until the early 70s. Most carriers operated on a linear point to point dispatch system until the late 70s when the hub and spoke became dominant. Jet airway routings between major business centers often were developed to approximate a great circle. In order to be most efficient, the boundaries of ARTCC’s were adjusted to fit the busiest routes within their areas.

    Look at the boundaries of ZLA, ZOA, ZLC, ZDV, ZAB, and ZKC. They are laid out on an ENE/WSW axis that fits the GC routing from the Chicago and the Northeast to California. The Eastern ARTCCs were laid out to fit the major traffic flows between ORD-MIA-BOS triangle. ZHU and ZFW handle the Southern Coast To Coast traffic

    The ARTCC boundaries have not changed a great deal in the last 60 years. Great Falls and Phoenix were consolidated in the 60s. Other ARTCCs have made minor adjustments over the years. DEN-SLC and CHI-MSP swaps may have been the biggest in land area.
     
  13. Salty

    Salty En-Route PoA Supporter

    Joined:
    Dec 21, 2016
    Messages:
    3,382
    Location:
    FL
    Display Name:

    Display name:
    Salty
    A lot of those lines follow mountain ridges for obvious reasons.
     
  14. flyingcheesehead

    flyingcheesehead Touchdown! Greaser!

    Joined:
    Feb 23, 2005
    Messages:
    22,216
    Location:
    UQACY, WI
    Display Name:

    Display name:
    iMooniac
    "Oh ****, it looks like that guy's gonna crash, I'd better hand him off quick." ;)
     
    TCABM and Briar Rabbit like this.