what is the floor of Class B airspace....

korben88

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....at addison airport (east of DFW)?

I got this wrong on a practice test and I'm not sure why.

The airport sits below the section of Dallas' Airspace that has a floor of 2500, but the class D shows a ceiling of 3000.

Doesn't the Class B floor overrule the Class D ceiling?
 
If you look carefully, part of their class D underlies the 2500 foot class B, but the east side of the class D underlies the 3000 floor of the class B. That's why it shows as 3000 for the class D.
 
Another question that is bordering on designed to confuse you. In real life you are going to be talking to someone in a location that is going to give you an altitude and heading until you are out of that mess. You have to contact DFW approach before you can enter ADS.

I'm going to say it is 2500
I may be wrong but that's my guess.

Given that ADS under the 30 is listed as [-30] I would assume the same is true for the 25 ring so ADS would be [-25] even though it isn't specified.
 
That is very interesting. I have never seen one like that. I've flown into many DFW airports but never KADS.
Subscribing here to follow the namecalling that is bound to ensue. :D
 
It looks like the question, related test supplement and correct answer have changed.

I have an old bank of questions from 2007.

Here's the 2007 version of this question and related chart from the old test supplement. This old chart shows Addison's delta as [-30] which means it stops just below 3000, and shows the bravo segment as [30/110] which means the bravo floor is exactly 3000. In other words, the correct answer used to be 3000.

Back then, the intermediate 25/110 ring segment didn't overlie Addison on the test supplement's chart, and 2500 wasn't even an option.

PPL_Test_Addison2.jpg


I don't have a current version of the question, but here's the current version of the chart from the 2016 test supplement.

It now includes an additional 25/100 bravo segment that is part of a new inner ring segment that overlies Addison, so the answer now is almost certainly 2500.

It's pretty sweaty of them to locate the (2) symbol so that it covers most of a bravo indicator that's displayed in a much smaller font than the other bravo indicators, and then ask a question about the little 25.

PPL_Test_Addison_2016.jpg


From a current chart on SkyVector, here's the 25/100 altitude indicator that they're partially covering up in the test supplement:

PPL_Test_Addison3.jpg
 
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I would have said 3,000' as well as Addison's airspace is surface to [-30]. Bravo is [30] to [110]
 
I would have said 3,000' as well as Addison's airspace is surface up to but not including [-30]. Bravo is [30] to [110]

FTFY. You can't have an Addison airspace up to [30] in this case, the "but not including" is very important.
 
But "AT" (or more like "directly over") Addison it is 2500.

I would agree with you but [-30] over Addison has to mean something and based on the answer choices above, 2,500 isn't even an option. There is a whole lot of ink in that area so it looks as if they squeezed in [-30] as close to Addison as they could get. That's my take on it and I'm probably wrong as usual.
 
But "AT" (or more like "directly over") Addison it is 2500.

Not necessarily. Class D isn't ALWAYS a ceiling of 2500. It's GENERALLY 2500.

Class D airspace is generally airspace from the surface to 2,500 feet above the airport elevation (charted in MSL) surrounding those airports that have an operational control tower. The configuration of each Class D airspace area is individually tailored and, when instrument procedures are published, the airspace is normally designed to contain the procedures.

644 + 2500 = 3144 which is more than 3000..so technically speaking, AT or above Addison, the class D is more like 2355, which is less than the typical 2500.
 
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Not necessarily. Class D isn't ALWAYS a ceiling of 2500. It's GENERALLY 2500.

Class D airspace is generally airspace from the surface to 2,500 feet above the airport elevation (charted in MSL) surrounding those airports that have an operational control tower. The configuration of each Class D airspace area is individually tailored and, when instrument procedures are published, the airspace is normally designed to contain the procedures.

644 + 2500 = 3144 which is more than 3000..so technically speaking, AT or above Addison, the ceiling of class D is more like 2355 heh..
That's not what I am using to judge it at 2500.

If you look close, you will see a very small 110/25 written on the slice of airspace over Addison...that's where I'm coming up with 2500. It actually does go up to 3000 farther east, where the class B rises.

Since it can't go all the way up to 3000 directly over the airport (as it would put it into the class B) it can only go to 2500.
 
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That's not what I am using to judge it at 2500.

If you look close, you will see a very small 25/110 written on the slice of airspace over Addison...that's where I'm coming up with 2500. It actually does go up to 3000 farther east, where the class B rises.

Since it can't go all the way up to 3000 directly over the airport (as it would put it into the class B) it can only go to 2500.

Yup..I think they put the "2" over it in attempt to hide any "ambiguity". If you look at a current chart through skyvector you get this:

upload_2017-3-9_14-0-59.png
 
So do we know the correct answer?
Often, the correct answer and the FAA "best" answer are two different things. Looking at the chart up close, I see that Addison class D has ceilings at 2000, 2500, and <3000, due to the class B floor.
 
more detail available on the terminal chart:
 

Attachments

  • image.jpeg
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Not necessarily. Class D isn't ALWAYS a ceiling of 2500. It's GENERALLY 2500.

Class D airspace is generally airspace from the surface to 2,500 feet above the airport elevation (charted in MSL) surrounding those airports that have an operational control tower. The configuration of each Class D airspace area is individually tailored and, when instrument procedures are published, the airspace is normally designed to contain the procedures.

644 + 2500 = 3144 which is more than 3000..so technically speaking, AT or above Addison, the class D is more like 2355, which is less than the typical 2500.

This post is a non sequitur. The question is about the floor of the Class B not the ceiling of the Class D; and it's in MSL.
 
It looks like the question, related test supplement and correct answer have changed.

I have an old bank of questions from 2007.

Here's the 2007 version of this question and related chart from the old test supplement. This old chart shows Addison's delta as [-30] which means it stops just below 3000, and shows the bravo segment as [30/110] which means the bravo floor is exactly 3000. In other words, the correct answer used to be 3000.

Back then, the intermediate 25/110 ring segment didn't overlie Addison on the test supplement's chart, and 2500 wasn't even an option.

I don't have a current version of the question, but here's the current version of the chart from the 2016 test supplement.

It now includes an additional 25/100 bravo segment that is part of a new inner ring segment that overlies Addison, so the answer now is almost certainly 2500.

It's pretty sweaty of them to locate the (2) symbol so that it covers most of a bravo indicator that's displayed in a much smaller font than the other bravo indicators, and then ask a question about the little 25..
Yep, I saw the 2016 test supplement which is exactly the reason I asked what the verbatim question and choices were.
Covering it suggests to me an accident - an error introduced during the revision. It wouldn't be the first time
 
This post is a non sequitur. The question is about the floor of the Class B not the ceiling of the Class D; and it's in MSL.

Heh, my numbers are in MSL too. If you look at the map that @Let'sgoflying! posted, I was in fact correct in my calculations in that 24 (the blue number exactly above the runway) is indeed what 2355 rounded up represents.

And the ceiling of one airspace abuts the floor of another. I fail to see how discussing the many variations of this airspace equates to non-relevance.
 
Heh, my numbers are in MSL too. If you look at the map that @Let'sgoflying! posted, I was in fact correct in my calculations in that 24 (the blue number exactly above the runway) is indeed what 2355 rounded up represents.

And the ceiling of one airspace abuts the floor of another. I fail to see how discussing the many variations of this airspace equates to non-relevance.

Where do you see 24?

Your post started with the idea the Class D is generally 2,500' AGL. The Class B floor above the airport, as shown on the chart, is 2,500' MSL, which is 1,855' AGL, so you completely lost me.
 
Where do you see 24?

Your post started with the idea the Class D is generally 2,500' AGL. The Class B floor above the airport, as shown on the chart, is 2,500' MSL, which is 1,855' AGL, so you completely lost me.

Open his attachment and look directly above the runway.

Airport elevation of Addison was (in the first supplement) 644 MSL. Most Class D airspaces extended 2500 ft MSL from the surface. 2500 + 644 = 3144 which would be IN the Bravo. Since it can't be in the Bravo and I can't lower the airport by 145 feet, I took 2500 - 145 to give me 2355. The supplement I found has the MSL elevation of the airport as now 645, so it would be 2354. The airspace around Addison makes for good conversation :).
 
Open his attachment and look directly above the runway.

Airport elevation of Addison was (in the first supplement) 644 MSL. Most Class D airspaces extended 2500 ft MSL from the surface. 2500 + 644 = 3144 which would be IN the Bravo. Since it can't be in the Bravo and I can't lower the airport by 145 feet, I took 2500 - 145 to give me 2355. The supplement I found has the MSL elevation of the airport as now 645, so it would be 2354. The airspace around Addison makes for good conversation :).

Dude I already looked at it before I entered the discussion. There is no 24 there, only a 25, which is the floor of the Class B which is 500 feet lower than the Class D ceiling. Since they overlap, the Class B takes precedence. So directly above the airport, the Class B floor is 2,500 MSL. Your 2355 (or 2354) has no relevance and no purpose in the discussion other than obfuscation.
 
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I'd have said 2500

image.jpg


But these little gotcha questions are one of the reasons I always just say to get the written done and it's just a box to check.
 
This is interesting. In my neck of the woods, we have this to deal with. At KFFZ (Falcon Field - Mesa, AZ), there is a small sliver of Bravo that over the KFFZ airspace that is specifically designated as 90/34, while KFFZ is [-34]. It looks like they put that little sliver in so as not to confuse people.


upload_2017-3-22_18-19-35.png
 
Similar cut out for KFTG right in KDENs backyard.

People bust the Bravo all the time by not turning left after departing on 26 by Imboden Road where the Bravo drops to the surface, or going north of 08/26. Or by climbing. The Delta top says -80, but the vast majority of the Delta is topped by the Bravo at 7000.

57a1338c350e7fc925dc4c084025969b.jpg


You also have to watch it if you're flying the ILS 35 VFR for practice. If you're at 7500 at ARRES you don't have very far to go to the 7000 shelf ahead.

d671980ef49a6e91d1974c1282272c0a.jpg


630809a1dd99299dfc785f16224c8fc0.jpg


(Yes, my house is way out on the far extended centerline almost of KFTG 35... at the airplane marker. Grin...)

DEN TRACON often will vector you onto the final right around there and NOT say the magic words, "cleared into the Bravo"... and almost acts annoyed if you ask if it's okay to clip the Bravo on the way down if you or the person you're safety pilot for isn't coming down right away at ARRES and is high on the glideslope. There isn't much wiggle room there.

The ILS 26 is also tight, too ... but a little better, in that you're at 7200 at SKIPI. You still need to be on your way down right now, at SKIPI though.

40f8260fcd059b79ee16e3be6b32781e.jpg


270872ed37703b8c446759ce4e5ce795.jpg


That's the charts.

In practice, DEN TRACON seems to not say a word as folks clip both edges flying the approaches VFR all the time, I'm sure.

They're talking to you and know where you are and forget to issue or don't want to issue the Bravo clearance about 99.99% of the time. So technically you need to drop. Quick.
 
My experience with FAA tests is that they are designed so no one ever gets 100%. There was one question on my IA test that was so confusing I simply threw a dart at it.
 
Similar cut out for KFTG right in KDENs backyard.

People bust the Bravo all the time by not turning left after departing on 26 by Imboden Road where the Bravo drops to the surface, or going north of 08/26. Or by climbing. The Delta top says -80, but the vast majority of the Delta is topped by the Bravo at 7000.

57a1338c350e7fc925dc4c084025969b.jpg


You also have to watch it if you're flying the ILS 35 VFR for practice. If you're at 7500 at ARRES you don't have very far to go to the 7000 shelf ahead.

d671980ef49a6e91d1974c1282272c0a.jpg


630809a1dd99299dfc785f16224c8fc0.jpg


(Yes, my house is way out on the far extended centerline almost of KFTG 35... at the airplane marker. Grin...)

DEN TRACON often will vector you onto the final right around there and NOT say the magic words, "cleared into the Bravo"... and almost acts annoyed if you ask if it's okay to clip the Bravo on the way down if you or the person you're safety pilot for isn't coming down right away at ARRES and is high on the glideslope. There isn't much wiggle room there.

The ILS 26 is also tight, too ... but a little better, in that you're at 7200 at SKIPI. You still need to be on your way down right now, at SKIPI though.

40f8260fcd059b79ee16e3be6b32781e.jpg


270872ed37703b8c446759ce4e5ce795.jpg


That's the charts.

In practice, DEN TRACON seems to not say a word as folks clip both edges flying the approaches VFR all the time, I'm sure.

They're talking to you and know where you are and forget to issue or don't want to issue the Bravo clearance about 99.99% of the time. So technically you need to drop. Quick.
What do they say when they give you the approach? Do they clear you for it and say maintain VFR, or do they approve it and say separation services will not be provided?
 
What do they say when they give you the approach? Do they clear you for it and say maintain VFR, or do they approve it and say separation services will not be provided?

One of those, depending on the controller. Sometimes all three.

But I don't believe "cleared for the approach, no separation services provided" counts the same as "cleared in the Bravo"... or does it?

I've gotten, "Cleared ILS 35 practice approach, maintain VFR, no radar separation services provided" as one big sentence more than once. Including on my Commercial ME ride. Then Approach forgot we asked for a full stop and/or the Tower forgot and had too much traffic and had us break it off to the south while I only had one engine producing power at 300 AGL. LOL.

The frequency congestion was high enough I looked at the DPE and said, "Can I have that back?" pointing at the idled engine throttle. Haha. It had suddenly gotten busy at FTG that afternoon. :)

He let me have it back while still under the hood and we did the SE landing at APA a few minutes later to satisfy the requirements. :) He said the approach looked great until they made me go away! Ha.
 
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