WineCountryUA

ATC can institute capacity limitations (for a variety of reason -- would suspect weather is the most common) -- limiting the number of takeoffs or landings or the number of flights in various air corridors. This is also sometimes called flow control or ground delay (SFO is great for losing the ability to use its parallel runways in the slightest weather situation).

Any of the above can lead to the airlines cancelling flights. This is reason regional flights can be a problem since a mainline and regional will count the same to ATC. So the airlines will trend to cancel regionals in favor of using the large mailine aircraft for the limited capacity allocations.

ATC caused delays (as with other weather delays) trend to get no compensation since they are beyond the ability of the airlines to control. UA will provide overnight lodging for in-route premium / 1K customers if needed and Rule 240 reroutes for others.

TerryK

That's what irked OP. Flights were not cancelled by ATC. Flights were cancelled by UA due to ATC delays.

Often1

Semantics. Of course, ATC doesn't cancel flights any more than the mechanical or the weather do. It's always UA that cancels the flight. The question is why UA cancelled the flight: ATC, WX, MX, flight crew out of time. Here, apparently the flight wasn't going to push in a time which would have allowed for adequate crew rest and so it was cancelled.

Welcome to the real world of air travel. It's nobody's fault and OP got to his destination, albeit fatigued.

aluminumdriver

Well, yes they can, in a way. If there is flow control into an airport, say ORD for example, they will limit the number of arrivals allowed per airline. With United having so many flights, they and American will be told they have to reduce their flights by say 10% during so and so hours. So do they cancel full 757's and 777's coming in, or a 50 or 70 seater? All about getting the most passengers in and out in the fewer slots available, as well as make up capability from the airport.

So, ATC doesn't come out and say United, you will cancel flight so and so but they do tell United that they have to cancel a certain number of flights. That's an ATC cancellation. Another one could be an ATC delay so long that the company decides to cancel the turn.

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fastair

AD hit it on the head. ORD capacity is (within a few) 112 landings per hour. All day today the ATC allowed between 40 and 56 landings/ hr for the majority of the morning, afternoon, and evening. So the 1st hour pushes 60 addl flights to the next hour, which pushes 120 flights into the next hour, which pushes 180 flights additional into the next hour. With capacity already pretty much maxed out, it would take days just to recover the 1st 3 hours of delays (not utilizing the middle of the night) with 12 hours more of additive backups. Without canceling some, the airport would realistically be backed up for an impractical time. So the airlines cncl some to ease ATC backups

freshairborne

Here is the FAA Arrival Demand Chart link. You can just enter any airport and it will give you the current and forecast demand capacity along with a lot of other info. Just make sure you put in the right stuff because GI=GO. This, along with the coveted cell phone number for one of the Central Flow Control dudes, is one of the things i use for planning my flights.

FAB

mduell

What's the mechanism for ATC or ATCSCC ordering cancellations? The only CDM/TFMS mechanisms I know can only assign delays and the airline decides how many and which to cancel.

ralfp

How does UA/CO treat an employee that's hours late to work because of traffic? What if it happens dozens of times a year? It's not the employee's fault that the road was over capacity during rush hour in inclement weather... how could the employee expect such a thing?

Sarcasm aside, truly rare/unusual ATC delays like an ATC hold into HPN can be excused. However, many flights are subject to ATC and/or weather delays so often that such delays are as normal as rush-hour traffic. Many flights are late > 50% of the time. Would UA or CO retain an employee that was late that often, even if all latenesses were due to traffic jams resulting from weather or heavy traffic?

An interesting WSJ article related to this topic.

freshairborne

You got it. The Feds say "you can only fly so many flights from here to there". That number might be one less than what's scheduled or it might be all of them. The airline will pick which ones to cancel, while minimizing collateral damage (to themselves, of course).

FAB


I have to say that, in my experience, EWR is truly the worst airport for delays I've ever flown into or out of. I hate flying near that place. And I saw a box of "Fresh Seafood" being belt-loaded onto my plane one day last summer when I was doing a walk-around in 98 degree heat. Mental note to self: don't eat in any seafood restaurants in Denver for the next week or so.

Just another reason to avoid EWR! (The people are nice, though)

FAB

kwildnj

75% of my travel is into/out of EWR, based on where I live, and the airline I choose to fly. Of that 75% of my travels, I have NEVER been delayed over 30 minutes of my scheduled departure/arrival time.

In fact, the only time which a late flight has caused me to miss a connection was out of PHL...

freshairborne

Then obviously, I'd love to have you on each and every flight I do into or out of EWR^

FAB

aluminumdriver

Each airline has an ATC coordinator that works for them in their Operations Center. They are in direct contact with all the centers. If there is a flow, these are the folks that get the call saying United can only have so many flights per hour. They pass that on to the operations center folks who start to prioritize flights based on capacity, connections, moving the most passengers, etc...

I think your attempted comparison is a little off the mark there. If an employee were to miss their flight a lot, they'd be in trouble and be at risk of losing their job. So, they'd need to either leave at a different time, take a different route or move.

As to the flight issue, if a flight is notoriously late/cancelled all the time, the DOT would see this as they track all the flights, and they would call United on it as a chronically late flight. United would then look at whether maybe fewer flights, with a bigger aircraft might be better, or just cancelling that flight that day, or various other factors. Just like I stated above, they'd look for a solution to that situation.

The problem with stations that are served by mostly RJ's, is United makes up for the fewer seats by more frequency. RJ's mess up the ATC system as they take up the same airspace and manhours from ATC, but move fewer people So when there is a flow control issue, United will be more inclined to cancel a flight on a RJ that may have 4 more flights that day, versus a mainline flight from a city that only has 2-3 mainline flights that day. When I look at a schedule board on weather days, easily 75% of the delays and cancellations I see are UAX aircraft.

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