Class D without ceiling

SkyHog

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So KAEG is towered now.

In anticipation, it appears the FAA marked the airspace around KAEG as Class D, before the tower went up. The most recent sectional shows it as Class D without an operating tower.

But there's no ceiling. GENERALLY, Class D goes up to 2500ft AGL, but that's not written in stone as far as I know. So how high does the airspace really, and legally go?
 
The answer lies within..

3-2-5. Class D Airspace

a. Definition. Generally, that 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 will normally be designed to contain the
procedures.
 
I thought in the AIM or the FAA Pilot Handbook of Aeronautical Knowledge it mentioned that it was 2500 feet above the airport elevation if not indicated by the [xx] in the dashed blue circle.

Don't have it here infront of me,.... if no one responds soon with a reference I'll get mine out and see if I can find it.

Edit... Looks like it was just posted above while I was typing.
 
I thought in the AIM or the FAA Pilot Handbook of Aeronautical Knowledge it mentioned that it was 2500 feet above the airport elevation if not indicated by the [xx] in the dashed blue circle.

Don't have it here infront of me,.... if no one responds soon with a reference I'll get mine out and see if I can find it.

Edit... Looks like it was just posted above while I was typing.
Yes, it's usually 2500 above airport elevation (rounded) but not always.
 
So KAEG is towered now.

In anticipation, it appears the FAA marked the airspace around KAEG as Class D, before the tower went up. The most recent sectional shows it as Class D without an operating tower.

But there's no ceiling. GENERALLY, Class D goes up to 2500ft AGL, but that's not written in stone as far as I know. So how high does the airspace really, and legally go?

It really and legally goes up to 7,500 MSL.


ASW NM D Albuquerque, NM​
Double Eagle II Airport, NM
(lat. 35°08'43''N., long. 106°47'43''W.)

That airspace extending upward from the surface to
and including 7,500 feet MSL within a 4.3-mile
radius of Double Eagle II Airport, and within 1 mile
each side of the Double Eagle Runway 22 ILS
localizer northeast course, extending from the 4.3-
mile radius to 5.9 miles northeast of the airport. This
Class D airspace area is effective during the specific
dates and times established in advance by a Notice to
Airmen. The effective date and time will thereafter be
continuously published in the Airport/Facility
Directory.​
AMENDMENTS 09/25/08 73 FR 39220 (Added)
 
It really and legally goes up to 7,500 MSL.


ASW NM D Albuquerque, NM​
Double Eagle II Airport, NM
(lat. 35°08'43''N., long. 106°47'43''W.)

That airspace extending upward from the surface to
and including 7,500 feet MSL within a 4.3-mile
radius of Double Eagle II Airport, and within 1 mile
each side of the Double Eagle Runway 22 ILS
localizer northeast course, extending from the 4.3-
mile radius to 5.9 miles northeast of the airport. This
Class D airspace area is effective during the specific
dates and times established in advance by a Notice to
Airmen. The effective date and time will thereafter be
continuously published in the Airport/Facility
Directory.​
AMENDMENTS 09/25/08 73 FR 39220 (Added)

According to Airnav, the elevation at KAEW is 5837 ft MSL, so a 2,500 ft AGL Class D would have a top at 8,337 ft MSL. Looks like they opted to allow a mere 1,663 ft AGL Class D here. Of course, some of it intersects ABQ's Class C, which comes down to 6,900 there, so there's some overlap. I don't know what they're going to do with the overlap. Presumably they'll draft a letter of agreement between ABQ Approach and KAEW tower and hopefully will chart it clearly. It's probably more complicated if the tower isn't 24x7, which I wouldn't expect it to be.
 
According to Airnav, the elevation at KAEW is 5837 ft MSL, so a 2,500 ft AGL Class D would have a top at 8,337 ft MSL. Looks like they opted to allow a mere 1,663 ft AGL Class D here. Of course, some of it intersects ABQ's Class C, which comes down to 6,900 there, so there's some overlap. I don't know what they're going to do with the overlap. Presumably they'll draft a letter of agreement between ABQ Approach and KAEW tower and hopefully will chart it clearly. It's probably more complicated if the tower isn't 24x7, which I wouldn't expect it to be.

Airspace does not actually overlap, the less restrictive classes give way to the more restrictive classes.

§ 71.9 Overlapping airspace designations.

(a) When overlapping airspace designations apply to the same airspace, the operating rules associated with the more restrictive airspace designation apply.

(b) For the purpose of this section—

(1) Class A airspace is more restrictive than Class B, Class C, Class D, Class E, or Class G airspace;

(2) Class B airspace is more restrictive than Class C, Class D, Class E, or Class G airspace;

(3) Class C airspace is more restrictive than Class D, Class E, or Class G airspace;

(4) Class D airspace is more restrictive than Class E or Class G airspace; and

(5) Class E is more restrictive than Class G airspace.
 
Airspace does not actually overlap, the less restrictive classes give way to the more restrictive classes.

§ 71.9 Overlapping airspace designations.

(a) When overlapping airspace designations apply to the same airspace, the operating rules associated with the more restrictive airspace designation apply.

(b) For the purpose of this section—

(1) Class A airspace is more restrictive than Class B, Class C, Class D, Class E, or Class G airspace;

(2) Class B airspace is more restrictive than Class C, Class D, Class E, or Class G airspace;

(3) Class C airspace is more restrictive than Class D, Class E, or Class G airspace;

(4) Class D airspace is more restrictive than Class E or Class G airspace; and

(5) Class E is more restrictive than Class G airspace.
So in this case the ceiling of Class D would be bounded by the floor of Class C where the "overlapping airspace designations apply to the same airspace", right?
 
So in this case the ceiling of Class D would be bounded by the floor of Class C where the "overlapping airspace designations apply to the same airspace", right?

Yes, the Class D ceiling is effectively at the Class C floor.
 
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As I look at the VFR Sectional over KAEG. The Class C to the Southwest only covers less than half of the Class D area. So it would appear that the Class D "should" have a shelf.
The Class D "should" only reach up to the floor of the overlying Class C at 6900MSL and then contiue on up to the published 7500MSL in the other ares, primarily over the airport and NW and along the ILS course.
 
So KAEG is towered now.

In anticipation, it appears the FAA marked the airspace around KAEG as Class D, before the tower went up. The most recent sectional shows it as Class D without an operating tower.

But there's no ceiling. GENERALLY, Class D goes up to 2500ft AGL, but that's not written in stone as far as I know. So how high does the airspace really, and legally go?

SkyHog,

You found it, so it's up to you to report the discrepancy to NACO by phone at 800-626-3677 or email at 9-amc-aerochart@faa.gov
http://www.naco.faa.gov
 
I also noticed the current published chart says "Class D by NOTAM".
Maybe it will be correct at the next publication cycle?
 
So in this case the ceiling of Class D would be bounded by the floor of Class C where the "overlapping airspace designations apply to the same airspace", right?

Yes, the Class D ceiling is effectively at the Class C floor.

But if the "legal" definition weren't 7500, but actually didn't have a ceiling, then the Class D would continue up from the ceiling of the Class C to the base of the Class A, then appear again at FL600, wouldn't it?
 
Airspace is defined by the TERPS. Don't have my copy handy, but when I talked to the FSDO about the FTG class D, that's the answer I got.

Want truly silly airspace? Take a look at FTG (SE corner of DEN) and what happens to the airspace when the tower is open and then when it's closed.
 
But if the "legal" definition weren't 7500, but actually didn't have a ceiling, then the Class D would continue up from the ceiling of the Class C to the base of the Class A, then appear again at FL600, wouldn't it?

But it were, and it do.
 
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