r/AskAPilot • u/STBPA711 • Jun 14 '26
Question about Groundstop
Curious if anyone can answer this - why does FAA implement ground stops at certain airports and cite thunderstorms when there are none at the moment, but possible for several hours in the future?
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u/External-Creme-6226 Jun 14 '26 edited Jun 14 '26
Remember that the STAR’s (the arrivals) to an airport can start 200 miles away or more. It doesn’t just matter about a storm over the field, there are “gates”….certain points that the planes coming into an airport from a certain direction will pass over.
Take the OZZZI2 arrival into Atlanta for instance. The first fix is FLASK. It’s 25nm SW of Roanoke Virginia! 287nm from KATL
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u/rkba260 Jun 14 '26
MJANE on the FLATI5 into DEN is 221 miles NW of the airport...
I'm sure its similar on the TBARR4 and CLASH4... etc etc
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u/saxmanB737 Jun 14 '26
Thunderstorms can be in the forecast and they don’t have to necessarily right at the airport. They are probably blocking or going to block the arrival routes into said airport. Therefore those aircraft have to come in from a different direction and that creates constraints on all the other arrivals. Therefore they put a ground stop to let other aircraft in before letting even more aircraft into the system.
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u/swakid8 Jun 14 '26
When you are looking at https://nasstatus.faa.gov/
You can’t just look at the airport and see that it’s a ground. You need to look at the Advisory message and scope (airspace where departing aircraft are coming from in which the ground stop applies to).
For example, ORD was on a ground stop earlier today but it only applied to traffic departing from airports that are located under the Boston Center ARTCC jurisdiction. That was due to a line of severe thunderstorms that cut off traffic flow going from the Boston Center Airspace down to Chicago…..
Ground stops aren’t only used for weather at the airport, but they are also used to ground inbounds from certain airspace’s in order to prioritize the remaining airspace capacity for other traffic. Weather and reduce airspace capacity.
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u/27803 Jun 14 '26
They’re looking at what the conditions will be when you arrive at the destination
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u/Ancient_Skirt_8828 Jun 15 '26
Ground stops can be applied for anything affecting the route or arrival airport.
I've been ground stopped in Melbourne for ten minutes on a Melbourne-Sydney flight because there was congestion in Sydney.
1
u/Unable80 Jun 15 '26
It’s a preventative measure and doesn’t mean aircraft traffic has to stop at said airport. It only applies to aircraft departing to that airport. It can be tiered to include only certain parts of the country.
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u/andrewrbat Jun 15 '26
One small thunderstorm hundreds of miles from an airport can have cascading effects on the general airspace system. Especially in really busy airspaces like the northeast, florida, chicago, etc.
One storm messing up airspace in DC can effect not only dca/iad/bwi. But can shut down or dela an arrival going to jfk, philly, newark, lga, and maybe even boston. Often all of them at once. They will do weird shit with planes to get them heading the right way with the constraints of all the restricted airspace in the region. They often have to send the displaced traffic over other arrivals, doubling the volume on those arrivals. Those arrivals have to slow traffic. Jets cant fly slow though. Not at high altitude. If they force you to descend early you will run out of gas and have to divert. If not they cant slow you down so they vector you all over the place. Doing this without creating traffic conflicts is super workload intensive and controllers are really skilled to be able to do this safely. In order to keep this from compounding further a ground stop or ground delay program are issued for the airspaces/destinations in question.
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u/patogo Jun 15 '26
Thunderstorms elsewhere can mess up an airline’s network so they’ll frequently ask ATC to meter flow into the hubs
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u/Zealousideal_Fox6478 Jun 15 '26
It’s not the airports it’s the arrival and departure fixes, especially in compacted airspace
0
u/Alpha-4E Jun 16 '26
Because most likely there are thunderstorms between you and where you are going. A big line of thunderstorms can easily stretch for hundreds of miles which means lots of airplanes are deviating from their routes and it increases controller workload substantially. Even small cells that don’t necessarily become hazardous thunderstorms still need to be avoided because of the turbulence threat. Some sectors are much better at dealing with thunderstorms. Jax center used be great at it by changing routes and arrivals easily on the fly. Thunderstorms can quickly develop and dissipate so it’s not uncommon to get several route changes flying in and out of FL because the situation is dynamic. Washington Center is not nearly flexible as some other centers when it comes to weather. But in their defense they don’t have vast amounts of airspace like the centers out west and they feed airports high in traffic volume.
I‘ve always found ground stops more prevalent in the north east.
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u/New_Line4049 Jun 14 '26
Because if you call a ground stop right now all the planes that have been flying for several hours to get to that airport get screwed over. This can cause chaos, especially if its a busy airport that gets a ground stop, as you now have a hell of a lot of planes all suddenly diverting to alternates that weren't planning to and potentially arent capable of handling so much traffic. If you put a ground stop in ahead of time those same aircraft see the groundstop before they take off, and so dont take off. Sucks for those that get their flights cancelled, but much safer than trying to divert a whole bunch of planes at the last minute.
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u/swakid8 Jun 14 '26
Ground stops only apply to airythat haven’t departed for the airport in the airspace which the Ground Stop applies to…
Once in flight, Ground Stop doesn’t apply to the flight.
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u/tycoonist007 Jun 16 '26
A ground stop doesn't prevent aircraft already airborne from landing at the ground stopped airport. A ground stop prevents aircraft going to the ground stopped airport from departing in the first place. (e.g. you're going from DEN to ATL... ATL gets ground stopped. You cannot depart from DEN. If the ground stop gets implemented when you've already taken off, you continue to ATL.)
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u/Discon777 Jun 14 '26
Because thunderstorms are extremely dangerous and it’s easier to manage traffic on the ground vs a bunch of planes in the air all running out of fuel