Two questions: Departure vs. Approach vs. Center AND Updrafts/Downdrafts

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Vas

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Vas
Hi all, I had two questions I am hoping the community might be able to help with.

First, how important is the distinction between departure/approach/center? Sometimes when I call approach for flight following, they identify themselves as departure. Sometimes they'll hand me off to another approach or departure frequency, and I call up (and say whatever the previous controller told me...) and they identify themselves as Denver Center (i.e., "Skyhawk 55555, Denver Center, proceed on course"). For example:

Denver Departure 1: Skyhawk 55555, Denver Departure, contact Denver Approach on 121.8.
Me: 121.8.
[Switch to 121.8]
Me: Denver Approach, Skyhawk 55555, 7,500.
Denver Center: Skyhawk 55555, Denver Center, proceed on route.

Is there any significance to these terms, does it matter what I use in terms of Approach, Departure, Center? Should I read anything into it if I'm talking to one versus the other? My inkling is that they're basically the same, but if Denver is landing south, North frequencies are Departure and South frequencies are Approach. But the "Center" threw me off. For east/west do they say "Center"?

Second, I recently encountered significant updrafts and downdrafts, which led to me reading the PHAK and a few advisory circulars as they pertain to updrafts/downdrafts. I feel like I have a good understanding of avoiding them and the circumstances in which they arise, and their dangers (especially microbursts). But what should I do if I inadvertently encounter them at low altitude (other than land).

Thanks in advance for your thoughts.
 
Approach and Departure are both radio callsigns for Terminal Radar Approach Control (TRACON), while Center is the callsign for an Air Route Traffic Control Center (ARTCC).

"Approach" and "departure" are usually interchangeable, as often a controller will work both departing and arriving traffic, except at very busy airports (and even then I doubt one would be upset by being called the wrong one). The choice of one over the other can provide context about your flight or intentions but that's it.

Centers are entirely different facilities though. If the controller is telling you he is handing you off to Denver Approach, and they answer with Denver Center, the controller that gave the handoff mis-spoke.
 
Terminal radar approach control (TRACON) is the radar service associated with Class B and C airspace. Center is the radar service outside the TRACON. Generally, Departure is the frequency and ATC label for aircraft departing the primary airport. The rest of the aircraft in the TRACON are using approach control. When you exit the TRACON, ATC service is provided by Center.

Microbursts are associated with thunderstorms. If you encounter one at low altitude you will likey crash and die because the downdraft will exceed the climb performance of your airplane by 5-10x. This is one reason the FAA advises you to avoid thunderstorms by at least 20 NM.

You might want to read up on mountain turbulence if you are in the Denver area.
 
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I appreciate that you looked in the PHAK for information. So few pilots do.

Approach and Departure is provided by the TRACON. At larger airports, the approach and departure functions may be on separate frequencies. At smaller airports, they are combined. It doesn't matter what you call them but you generally will use "departure" when you are departing and "approach" when you are arriving and when you are transitioning their airspace.

Center is one of the Air Route Traffic Control Centers (ARTCC). They do things differently from TRACON and you'll notice some differences is how they provide radar traffic advisory services. If you call them "approach", it won't be the first time someone did. It is part of their radio call sign, though, so you should at least try to get it right most of the time.

You'll find information on TRACON and ARTCC services in the AIM.

Microbursts will be associated with convective activity. You should be aware of that and give building cells plenty of room.

You can also get strong up/down drafts from mechanical turbulence when the wind is blowing over mountainous terrain. If you are in such areas, stay aware of the winds and read more about mountain flying.

Typical summer thermals are common and come from uneven heating. As you fly over different surface conditions, i.e. water, land, pavement, etc., the air movement will change. They can be uncomfortable, but are rarely dangerous.
 
Vas said:
Hi all, I had two questions I am hoping the community might be able to help with.

First, how important is the distinction between departure/approach/center? Sometimes when I call approach for flight following, they identify themselves as departure. Sometimes they'll hand me off to another approach or departure frequency, and I call up (and say whatever the previous controller told me...) and they identify themselves as Denver Center (i.e., "Skyhawk 55555, Denver Center, proceed on course"). For example:

Denver Departure 1: Skyhawk 55555, Denver Departure, contact Denver Approach on 121.8.
Me: 121.8.
[Switch to 121.8]
Me: Denver Approach, Skyhawk 55555, 7,500.
Denver Center: Skyhawk 55555, Denver Center, proceed on route.

Is there any significance to these terms, does it matter what I use in terms of Approach, Departure, Center? Should I read anything into it if I'm talking to one versus the other? My inkling is that they're basically the same, but if Denver is landing south, North frequencies are Departure and South frequencies are Approach. But the "Center" threw me off. For east/west do they say "Center"?

Second, I recently encountered significant updrafts and downdrafts, which led to me reading the PHAK and a few advisory circulars as they pertain to updrafts/downdrafts. I feel like I have a good understanding of avoiding them and the circumstances in which they arise, and their dangers (especially microbursts). But what should I do if I inadvertently encounter them at low altitude (other than land).

Thanks in advance for your thoughts.
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Like said above the distinction between Approach and Departure is really no thing. They are both a function within an Approach Control Facility known as a TRACON, an acronym of Terminal Radar Approach Control. Airspace in the US is allocated to Air Route Traffic Control Centers. They in turn delegate Airspace to the TRACONS. Here is a map showing the boundaries of the Centers.

upload_2021-11-8_5-13-23.png
 
Clip4 said:
Terminal radar approach control (TRACON) is the radar service associated with Class B and C airspace. Center is the radar service outside the TRACON. Generally, Departure is the frequency and ATC label for aircraft departing the primary airport. The rest of the aircraft in the TRACON are using approach control. When you exit the TRACON, ATC service is provided by Center.

Microbursts are associated with thunderstorms. If you encounter one at low altitude you will likey crash and die because the downdraft will exceed the climb performance of your airplane by 5-10x. This is one reason the FAA advises you to avoid thunderstorms by at least 20 NM.

You might want to read up on mountain turbulence if you are in the Denver area.
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Yeah. A little thing to add though. There are many TRACONS that are not at Class B and C's.
 
Approach, departure? I don't worry about it. As long as I dialed in the correct frequency, I'll just start with my call sign. They know who they are, and they don't hesitate to tell me who they are when they answer.

Updrafts and downdrafts? That covers a wide range of phenomena. Associated with t-storms they are bad news, but easy to avoid most times. Associated with mountains? Can be bad news too, sometimes harder to avoid, but good preflight will keep you away from bad situations.
 
Thanks everyone, this is super helpful.
 
You also have military equivalent to TRACONs as well. As stated above, they may or may not be associated with a class B or C. They might refer to themselves as approach or departure. Don’t sweat it if you call them the wrong term, they’re essentially the same. On a rare occasion you might even talk to “Arrival” that works a lower altitude or a “GCA” (Ground Controlled Approach) that’ll generally just work you on final.

A932388F-D7D7-45F0-80D3-A30A6A71D9F8.jpeg
 
Clip4 said:
Microbursts are associated with thunderstorms. If you encounter one at low altitude you will likey crash and die because the downdraft will exceed the climb performance of your airplane by 5-10x. This is one reason the FAA advises you to avoid thunderstorms by at least 20 NM.
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That’s a bit hyperbolic.

The big discovery some time back was that the downbursts associated with thunderstorms could be particularly dangerous for even the most powerful jet airliners. It wasn’t that the vertical velocity of the downbursts could dash them into the ground but rather the combination of encountering a sudden strong headwind during approach followed by a strong downdraft, followed by a strong tailwind, could cause the pilot (or autopilot?) to get behind the need to apply full power and get the hell out of there. Instead the pilot might initially reduce power and then given the lag inherent in jet engines, would be unable to increase power enough to compensate for sudden downdraft followed by a strong tailwind.

Staying out of strong convective activity is not only recommended but easier to do now than ever before. You probably stand a better chance of surviving a microburst in a piston airplane than a jet. In any case, downdrafts don’t exist at ground level and they can’t exceed the full power climb capability of an aircraft when close to the ground. A sudden change in horizontal winds might exceed ones ability to compensate. In any case, they are dangerous as hell but it’s useful to understand how they work.

But I’m just a glider guider and light plane flier pontificating about stuff I just barely know much about, so there’s that.


Sent from my iPad using Tapatalk Pro
 
Velocity173 said:
You also have military equivalent to TRACONs as well. As stated above, they may or may not be associated with a class B or C. They might refer to themselves as approach or departure. Don’t sweat it if you call them the wrong term, they’re essentially the same. On a rare occasion you might even talk to “Arrival” that works a lower altitude or a “GCA” (Ground Controlled Approach) that’ll generally just work you on final.

View attachment 101713
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I think the Navy and Air Farce started calling them TRACON's a year or so ago.
 
luvflyin said:
I think the Navy and Air Farce started calling them TRACON's a year or so ago.
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I don’t know but I’m still reading AF pubs dated this year that still refer to approach facilities as RAPCONs.
 
Velocity173 said:
I don’t know but I’m still reading AF pubs dated this year that still refer to approach facilities as RAPCONs.
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I was just looking for a reference to it but couldn't find it. I musta had it confused with something else.
 
Vas said:
...Second, I recently encountered significant updrafts and downdrafts, which led to me reading the PHAK and a few advisory circulars as they pertain to updrafts/downdrafts. I feel like I have a good understanding of avoiding them and the circumstances in which they arise, and their dangers (especially microbursts). But what should I do if I inadvertently encounter them at low altitude (other than land)...
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I once flew into a tiny microburst. Couldn't have been more than a quarter-mile in diameter--maybe less. We were VFR, descending into downwind at Ellensburg, WA (ELN)

On the 45, approaching Ellenburg's (ELN) 07 (The Great White Way), a very small, contained rain squall was clearly visible over the downwind leg to 07 moving east. At pattern altitude, 1000 AGL, we rolled onto a left downwind heading west and into the squall. Immediately we began losing altitude. Rain streamed across the windscreen. It was a micro-burst, with lots of cold air being pulled down with the rain and us with it. Full power, maximum up elevator, and we were still descending. Just as I was about to turn out of the pattern to the north, we cleared the squall and began gaining altitude.Turning to final, we saw the tiny squall moving off eastward. The damned thing looked to be only a couple thousand feet in diameter. The landing was uneventful and welcome.

Luckily, it was tiny and clearly visible, that is, I knew it was tiny and we'd be out of it quickly. Had it been larger or obscured, not sure how things would have ended. It was a tense few seconds and an altitude loss of about 400 feet. Obviously, I should have recognized it and should not have flown into it. It was a humbling, learning experience I'll never forget.
 
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