Airspace between Class B upper limits and Class A

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manlymatt83

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Matt
Curious... new-ish student pilot, here.

The above limit for Class B airspace varies, but over NYC, it's 7000 feet. Does that mean a pilot flying VFR at 7500 feet over the Class B could intercept Jet Traffic ascending up into the Class A controlled airspace? I realize VFR flying requires separation, but what's to stop a jet coming out of the clouds from below (provided VFR operations above the clouds)?
 
John221us said:
Mode C veil
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Sort of but this is only part of the answer. The mode C veil requires you to have an altitude encoding transponder installed if you have an electrical system and plan on flying within 30 NM of a class B airport.

This allows ATC to see you even if you are flying VFR and not talking to anyone. The aircraft that you are worried about are either flying through a cloud, as you mentioned, and would be under positive control on an IFR flight plan or, if VFR, exiting the class B airspace and would have been notified of your presence by ATC.

Don't forget to look out the window, I bet the big guys are looking back.
 
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red4golf said:
Sort of but this is only part of the answer. The mode C veil requires you to have an altitude encoding transponder installed if you have an electrical system and plan on flying within 30 NM of a class B airport.

This allows ATC to see you even if you are flying VFR and not talking to anyone. The aircraft that you are worried about are either flying through a cloud, as you mentioned, and would be under positive control on an IFR flight plan or, if VFR, exiting the class B airspace and would have been notified of your presence by ATC.

Don't forget to look out the window, I bet the big guys are looking back.
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I agree, see and avoid. I was only highlighting that you should be visible to ATC. In my area, I always have FF near class C and B anyway. It keeps me out of trouble.
 
John221us said:
I agree, see and avoid. I was only highlighting that you should be visible to ATC. In my area, I always have FF near class C and B anyway. It keeps me out of trouble.
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Just filling in the blanks since I can't sleep.....

I fly from either KPLU or KOLM and spend a lot of time in the Mode C veil of Sea-Tac (KSEA) and I'm ALWAYS on FF when going north.

One time I had a 737 called out to me at something like 10 o'clock and 2 miles but all I could say is "looking".

ATC said that it was the big silver thing to my left.....

There was one little puffy could in the sky that just happened to hide the 737 perfectly. I was laughing so hard at their reply that I could hardly say "traffic in sight".
 
that's why it is 1000ft above and either 2000ft or 1Mi horizontal... To give you some time to see and avoid those guys poking up through the clouds and accounting a bit for the probable speeds they are ascending.

FF should be your best friend if your going to fly under, over, through, and near class B. I'm under a busy little airports B (DFW) and I'm on FF 90% of the time.
 
I've had jets pop up out of the Chicago class B in VFR conditions. Of course they popped back down again when TCAS gave them an RA.
 
1. Yes, you could / will encounter large jet traffic in such an area (the wormhole teleporter between B and A is currently NOTAM closed for maintenance).

2. Get flight following so you're talking to the people talking to those big jets.

3. You will also encounter big jets under and horizontal to the B depending on the day's patterns. For this too see #2
 
I pretty much stay away from B [going past Atlanta, I get vectored if IFR and not cleared in when VFR] and almost always have flight following. Even when VFR, I've had departure at Class C halt jet climbs and watched them pass under me before they are cleared higher. Nice guys on the ground! I return the favor and tell them when the big guys are clear to resume climb.
 
Yup, you sure can.

And if you're on flight following, it will be announced with something like "United 1234 heavy approach remain below 6000." BTDT.

It's kinda cool to have something real big restricted below your spam can. :)
 
MAKG1 said:
Yup, you sure can.

And if you're on flight following, it will be announced with something like "United 1234 heavy approach remain below 6000." BTDT.

It's kinda cool to have something real big restricted below your spam can. :)
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Until ATC misses one and they climb into your path and then push over in response to an RA.
 
manlymatt83 said:
The above limit for Class B airspace varies, but over NYC, it's 7000 feet. Does that mean a pilot flying VFR at 7500 feet over the Class B could intercept Jet Traffic ascending up into the Class A controlled airspace? I realize VFR flying requires separation, but what's to stop a jet coming out of the clouds from below (provided VFR operations above the clouds)?
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Nothing. In fact, the whole idea of B-space is for the jets to drop in from the top and exit up through the top (not through the sides). So if you're going over the top of B-space, it would be a really good idea for you to be talking to the ATC facility covering that area even though the regulations don't require it.
 
Ron Levy said:
In fact, the whole idea of B-space is for the jets to drop in from the top and exit up through the top (not through the sides).
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Ron,

You have a source for that?

I routinely commuted under the Miami TCA, and it sure seemed jet traffic entered from the sides.

And the handful of times I overflew it or NYC, it also sure appeared that way as well.

I thought that was the whole idea of the "upside-down wedding cake".
 
FastEddieB said:
Ron,

You have a source for that?

I routinely commuted under the Miami TCA, and it sure seemed jet traffic entered from the sides.

And the handful of times I overflew it or NYC, it also sure appeared that way as well.
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That was the original idea when TCA's were first proposed around 1973. Sorry, I don't think there's a link to that original NPRM unless someone researches it in the Federal Register. In addition, the current version of FAA Order 7110.65 tells controllers not to route "large turbine-powered aircraft" below the floors of Class B airspace, so they should not be entering from the side other than above the highest floor.
 
I think the goal is for them to enter the top, but it doesn't always work out that way.
 
I thought the point of B airspace was to contain all the instrument approaches. That doesn't mean the transitions don't enter from the side.

E.g., SFO ILS or LOC 28R starts at ARCHI intersection at 7000 (restricted above and below), which is just barely inside the B at that altitude. To get there, it's unavoidable to enter the airspace from below the top shelf.
 
MAKG1 said:
I thought the point of B airspace was to contain all the instrument approaches. That doesn't mean the transitions don't enter from the side.
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The original intent was to contain all large/turbine aircraft operations below the ceiling of the TCA. Having those aircraft enter from the side was not part of the original plan. How it as been bastardized since then is another story.
 
Like I said, I'm pretty sure I was taught this way (arrivals entering from the side of the upside-down wedding cake), complete with diagrams, from the very beginning when they were TCA's. Also pretty sure I taught this at Burnside Ott and then to all of my students thereafter.

If that's wrong, I owe a lot of folks an apology and a correction! :eek:
 
Could someone use FlightAware and take a look at arrivals into Miami, let's say, and plot altitudes on the way in?

That should settle what's going on "in real life".
 
They probably always enter through the surface where the Mode C vail meets 10,000 ft, so in theory the heavy iron should always be in airspace where TCAS would work...?
 
FastEddieB said:
Could someone use FlightAware and take a look at arrivals into Miami, let's say, and plot altitudes on the way in?

That should settle what's going on "in real life".
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Miami may not be a representative example. It seems almost every time I land MIA, I enter from the side.... OF THE LOWER TIER. It's the only place I get routinely vectored and the say "you will be under the class bravo" as I'm on final. Yes, I'm in a jet flying IFR.
 
In my observation for a few class B's I bump into regularly (DC, NY, and Chicago), departures do regularly pop out the top. Arrivals usually come in through the sides.
 
Sheesh.... It's not only my class B's you need to be concerned with. You should always be looking for other aircraft. That also applies to the "big guy" coming out of the the Bravo. I am s "big airplane guy", and I'm always looking for traffic.. (Unless I'm above FL180. And then I am on o limited basis). Point is, the "big sky theory", although very good, is far from perfect.

That's a bunch of gobledegook... Get flight following and all is well. (But still look outside).
 
red4golf said:
Sort of but this is only part of the answer. The mode C veil requires you to have an altitude encoding transponder installed if you have an electrical system and plan on flying within 30 NM of a class B airport.



This allows ATC to see you even if you are flying VFR and not talking to anyone. The aircraft that you are worried about are either flying through a cloud, as you mentioned, and would be under positive control on an IFR flight plan or, if VFR, exiting the class B airspace and would have been notified of your presence by ATC.



Don't forget to look out the window, I bet the big guys are looking back.
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Your still require a transponder over the top of class B, even with out an electrical system.

(3) Notwithstanding paragraph (b)(2) of this section, any aircraft which was not originally certificated with an engine-driven electrical system or which has not subsequently been certified with such a system installed, balloon or glider may conduct operations in the airspace within 30 nautical miles of an airport listed in appendix D, section 1 of this part provided such operations are conducted—

(i) Outside any Class A, Class B, or Class C airspace area; and

(ii) Below the altitude of the ceiling of a Class B or Class C airspace area designated for an airport or 10,000 feet MSL, whichever is lower; and


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Kritchlow said:
Miami may not be a representative example. It seems almost every time I land MIA, I enter from the side.... OF THE LOWER TIER. It's the only place I get routinely vectored and the say "you will be under the class bravo" as I'm on final. Yes, I'm in a jet flying IFR.
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That's my observation.

I was routinely back and forth from OPF or HWO to TMB staying just under one of the tiers (at 1,400' just below the 1,500' floor) and the jets were right above me on east operations. No way were they coming in "from the top".

ClassB-C.jpg


So my perception may be off if MIA is an exception.
 
VanDy said:
Your still require a transponder over the top of class B, even with out an electrical system.

(3) Notwithstanding paragraph (b)(2) of this section, any aircraft which was not originally certificated with an engine-driven electrical system or which has not subsequently been certified with such a system installed, balloon or glider may conduct operations in the airspace within 30 nautical miles of an airport listed in appendix D, section 1 of this part provided such operations are conducted—

(i) Outside any Class A, Class B, or Class C airspace area; and

(ii) Below the altitude of the ceiling of a Class B or Class C airspace area designated for an airport or 10,000 feet MSL, whichever is lower; and


Sent from my iPhone using Tapatalk
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Doesn't (3)(ii) right there say you don't need one on top, since the ceiling of the B is below you if you're on top?
 
No it does not. The clause is defining where you HAVE to be if you're using the exception. You must be outside the class B and below it's top or 10,000' which ever is lower.

There's extraneous verbiage there. What class B or C do we have that's not designated for an airport in the US?
 
Airports with parallel runways require the IFR arrivals to turn onto their respective finals 1000' feet vertically separated, which usually means the higher altitude needs to be quite a ways from the airport and potentially outside the class B.

At ORD, the jet arrivals typically enter from the top from the far arrival fixes, and from the side on the close arrival fixes. Departures usually climb out pretty close to both the top and side at the same time, but then the MDW departures are restricted below the ORD departures, which is usually in the B (even though they started in a C).
 
VanDy said:
Your still require a transponder over the top of class B, even with out an electrical system.

(3) Notwithstanding paragraph (b)(2) of this section, any aircraft which was not originally certificated with an engine-driven electrical system or which has not subsequently been certified with such a system installed, balloon or glider may conduct operations in the airspace within 30 nautical miles of an airport listed in appendix D, section 1 of this part provided such operations are conducted—

(i) Outside any Class A, Class B, or Class C airspace area; and

(ii) Below the altitude of the ceiling of a Class B or Class C airspace area designated for an airport or 10,000 feet MSL, whichever is lower; and


Sent from my iPhone using Tapatalk
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aarrrggghhhh.... Ya got me!
 
red4golf said:
Just filling in the blanks since I can't sleep.....

I fly from either KPLU or KOLM and spend a lot of time in the Mode C veil of Sea-Tac (KSEA) and I'm ALWAYS on FF when going north.

One time I had a 737 called out to me at something like 10 o'clock and 2 miles but all I could say is "looking".

ATC said that it was the big silver thing to my left.....

There was one little puffy could in the sky that just happened to hide the 737 perfectly. I was laughing so hard at their reply that I could hardly say "traffic in sight".
Click to expand...

I love those guys at SEA approach and center. They really are great to work with.

Coming back from eastern Washington heading into KOLM one day a number of years ago we were on FF and the CFI I was flying with wanted to get some pictures of Mt. Rainier from a bit closer. So we turned towards the mountain. SEA center came up on the radio and said, "I know what you're doing!" with a smile in his voice. I replied that he was right and that we'd be returning to our course to KOLM shortly. Another wonderful day flying in the PNW.
 
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