Class E Surface Area designated for an airport

Visual Graphic to Understand Class E Surface Area

We normally launch in Class G airspace and climb into Ek which starts at 1200 (or 700′) AGL and goes up to 18,000′.

We canNOT fly in or over the “lateral boundaries of the surface area of Class E airspace designated for an airport” without permission (like that below). But there’s more to it. Here’s more on why we can’t fly OVER it..

In the depiction above, green is the boundary between G (think G for Ground) and E (just about Everything else). Dashed magenta lines mean E airspace drops to the surface — “Class E surface area.” This one goes all the way around the airport. That’s significant.

There are some class E surface areas that we CAN fly in. Read on.

Various FAA documents specify two types of Class E surface area:

  • those designated for an airport, (requires permission) and
  • those designated as an extension (we can fly here withOUT permission).

You can see these differentiated in both the FAA Aeronautical Information Manual (AIM) 3-2-6, and the 1500+ page airspace tome FAA Order JO 7400.9 Airspace Designations and Reporting Points (excerpt below) which lists every single airport with E surface airspace. Airport surface areas, dubbed “E2”, are listed under section 6002, and extensions, sprouting from towered airports, dubbed “E4”, are listed under section 6004. Section 6003 lists extensions from B and C airports.

An exciting episode from FAA Order JO 7400.9 Airspace Designations and Reporting Points

We canNOT fly in airport E surface areas (like the one above or airport 1 or 2 below).

We CAN fly in the E surface extensions (like airport 3 below). We can even fly in extensions from class B or C airports (dubbed E3).

There may be airports out there that have a complete dashed magenta circle AND magenta extensions, but I haven’t found one. If you do, where you can see they’re delineated as extensions, then we can fly there. Weird. Arcane.

The ultimate test is to see if the surface area in question is listed in JO 7400.9 as E3 (extensions to B/C airspace) or E4 (extensions to D/E airspace). If so, we can fly there, other factors permitting.


Class E surface area of any type is depicted with magenta dashed lines.

Below are descriptions of the types of Surface area and whether we can fly in the extensions. You can get permission for the airport E surface area by calling the Air Route Traffic Control Center or approach control that’s responsible.

Class E Surface area designated for an airport

Above is another example of “the lateral boundaries of the surface area of Class E airspace designated for an airport”. It’s defined under JO 7400.9 section 6002 (E2) and we can’t fly here without permission.

Class E Surface area with Class E surface extensions


Galesburg (above) is also “the lateral boundaries of the surface area of Class E airspace designated for an airport”. We know because its geometry is defined under JO 7400.9 section 6002 as E2 airspace including the tabs that look like extensions but are not called extensions, they’re part of area’s definition. The piece of JO 7400.9 that defines Galesburg’s E surface area is shown below (irrelevant other airport info blacked out). We can’t fly here without permission.

And lastly…

Class D with E Surface Area designated as extensions

The primary airport (above) is D airspace where we need permission from the tower. But the extensions are listed as such under JO 7400.9 section 6004. They are E4 and we do NOT need permission to fly in them.

Few FAA people will know this. I’ve asked. It wasn’t until I was shown the documents and studied them a bit that I saw clearly how it works and what their intent was: to keep us away from moderately busy airports without permission.

As an aside, I have gotten permission from the controlling agency (Air Route Traffic Control Center) to fly from these airports but expect them to be surprised because regular aircraft do not need permission.

Justification For Interpretation

FAR 103.17 doesn’t just say “Class E Surface area,” it adds “designated for an airport.” Both the AIM and JO 7400.9 (that defines each individual airport) differentiates “designated for an airport” and “designated as an extension,” showing that they didn’t mean to exclude us but rather just require us to mind the higher visibility and cloud clearance requirements.

If you think there’s a better supported interpretation, please Email me at the Contact address. Include supporting document references with your explanation. Thanks!

Updated 2018-02-09  thanks to Bryan Schwartz and “aeroexperiments” on