How Do I Know Which Feed When Tracking My Flight

[BravoLima]

If I wanted to listen to comms with a flight I was on how do I know which one they'd be on especially at a big airport like ORD?  Its easier on takeoff because they'll say which freq to contact but on arrival?  For example I was on a TPA-ORD flight and we were approaching from the southeast over Indiana.  So I figured it would be on the Approach SE Feeder but that's not it because they were talking to planes approaching over Lake Michigan from the northeast (on the SE feeder frequency!)  Then I tried the approach secondary feed and I found them, but the times don't match.  At 28 minutes in the audio clip my flight came on and checked in at 7,000ft but at 1428z they were several miles ahead and down to 6700ft.  And who would they be talking to before approach secondary?

[KB4TEZ]

Without knowing which flight you were on, my guess would probably be Chicago Center, before the hand off to Approach, then to Final, then to tower.
John

[JetScan1]

If I wanted to listen to comms with a flight I was on how do I know which one they'd be on especially at a big airport like ORD? 

I'm not that familiar with ORD Approach but they do use different sector configurations depending on the time of day and traffic volume. The SE feeder sector, where you would expect to have heard it, might have been combined with another sector at the time. Any chance you can provide the date and flight number, and we might be able to figure it out ? Prior to ORD Approach the flights from the SE via BONNT and the VEECK STAR (typical route from TPA) would be handled by Chicago Center on 134.875 but it's not covered by LiveATC.

KB4TEZ,

Where did you get that map from ?

[JetScan1]

Just checking some archives and I see they use the SW frequency 135.075 for the SE feeder sector at times. Might catch them there. Also when traffic is light they bypass the feeder sectors and go directly to Approach. Re that chart: I see it's off the ZAU IVAO site. I wonder what their source was ? I've been looking for charts that depict Approach Control airspace like that for other areas.

[KB4TEZ]

Jetscan1 here ya go !
https://wiki.us.ivao.aero/atc/sop/kzau

[JetScan1]

Jetscan1 here ya go !

Thanks. I also found a copy of the TRACON SOP Manual (2017) that you can download here.

https://www.documentcloud.org/documents/5763110-C90-SOP/

They seem to like to switch up their frequencies, recently they have been using the Loop Departure frequency 118.275 for arrival final to 10C, and 135.075 to feed SE arrivals.

[BravoLima]

I was on NK3492.  Also with regard to the Center frequencies how would I know which sector number? 

I was also on NK2076.  They would have been on a ZLA frequency, coming in from the northeast, but I have no idea which sector before they got handed off to LAS Approach.

[KB4TEZ]

here's a pretty decent site I use
https://www.radioreference.com

ZAU example attached

[JetScan1]

I was on NK3492.

I'm guessing ORD was landing west at the time which explains why you didn't hear them on the SE Feeder frequency. From what I've heard so far, when ORD is landing west the SE Feeder sector is not used and flights are handed off directly from the Center 134.875 to the Final Approach frequency, typically 133.625 for runway 28C around that time.

Also with regard to the Center frequencies how would I know which sector number?

A few years ago I posted some High Altitude Charts in the "ARTCC/FIR/TRACON Maps" Forum that are still "mostly" accurate. Might be helpful ?

https://forums.liveatc.net/artccfirtracon-maps/tracking-flights-coast-to-coast-from-takeoff-to-landing-is-this-possible/

https://forums.liveatc.net/artccfirtracon-maps/high-altitude-chart-zbw-zob-zdc-zau-zid/

I was also on NK2076.  They would have been on a ZLA frequency, coming in from the northeast, but I have no idea which sector before they got handed off to LAS Approach.

124.200 ZLA Sector 07. It's not covered on LiveATC.

[RonR]

A short time ago I put together an ORD arrivals map (sort of lol).  After some extensive research (listening for hours lol), this map gives a fairly accurate idea of what frequencies Chicago Tracon uses for approaches to ORD.  It's handwritten so hopefully it's understandable.  Hopefully it helps!

Ron

[JetScan1]

A short time ago I put together an ORD arrivals map

Using the chart from that SOP document I added the STAR names and frequencies. This is just based on monitoring over the last week but seems consistent with what you heard Ron. On the SOP chart it appeared to show when landing east that the TRTLL STAR was one used as a secondary from the SW but so far I've only heard them use the BENKY STAR as a secondary to SHAIN, so I added it to my chart. The few times I checked they were using 128.575 as the overnight frequency.

[RonR]

Yea, you're right, they have stopped using 125.0 altogether as far as I can tell apparently bc of interference on that frequency.  Forgot to update my handwritten chart lol!  Thanks!