Airspace Regulations & Sectional Charts

Introduction

The airspace above the United States is chopped up and regulated in six different ways, largely based on the location of airports all across the country.

These six classifications define where and when air traffic control must take control to ensure safe takeoff and landings. They range from the unregulated airspace amongst the Rocky Mountains to the tightly controlled skies around busy airports like JFK or Logan.

For the test, you’ll need to know about each classification of airspace, the corresponding regulations, and whether drone flight is permitted.

That’s the easy part.

The harder part—and the part that you will encounter more than anything on the test—will be reading the incredibly dense sectional charts that communicate everything from airspace regulations in certain areas to the height of half-finished buildings and the presence of weather balloons. It takes practice, but once you learn how, it will feel like you speak a hieroglyphic language.

Airspace Regulations

Class A Airspace

Above everything – 18,000ft MSL to FL600

Class A airspace is the cruising lane for passenger jets. It extends from 18,000ft above sea level (MSL) to Flight Level 600 (FL600), which is 60,000ft MSL

As a drone pilot, you won’t be interacting with anything over 18,000 feet, and you likely won’t encounter any questions about Class A airspace on your test. So just know that class A exists above everything else and focus on the other classifications.

Class B Airspace

Busiest Airports
Surface – ~10,000ft MSL
Requires Air Traffic Control Authorization

A depiction of class B airspace.

Class B airspace surrounds the nation’s busiest airports like JFK, Logan, and LAX. Resultantly, much of the airspace above the country’s big cities is Class B as well.

Class B airspace is shaped like an upside down wedding cake, with each subsequent tier extending further out from the center. The first tier—the area immediately around the airport—is controlled from the “floor,” or ground level, up to the “ceiling” at around 10,000ft MSL.

(By the way, the reason I’m saying around 10,000ft is because all airspace designations are slightly different. The details of a specific area will be defined in the region’s “sectional chart,” which we will learn to read later in this section.)

At around 2,500ft, a second tier of Class B airspace juts outward, leaving room beneath it for other classifications. The floor of this second tier begins at 2,500ft and continues to the ceiling at 10,000ft. Finally, at around 5,000ft, a third tier begins.

Class B airspace is designed to protect large planes as they take off or descend towards an airport, so the “floor” of Class B airspace gets closer to the ground as it gets closer to the airport.

All aircraft passing through Class B airspace need permission from Air Traffic Control to do so. As a drone pilot, you will need to apply for authorization before you think about operating in Class B airspace.

Class C Airspace

Control Tower
Surface – 4,000ft AGL
Requires Air Traffic Control Authorization

Generally, Class C airspace is a scaled-down version of Class B airspace with only two tiers instead of three. It surrounds comparatively less busy airports that meet certain requirements (which the FAA won’t ask you about).

Similar to Class B, the first tier begins at the surface and continues to the ceiling at about 4,000ft. At around 1,200ft

Just like Class B airspace, pilots need permission from Air Traffic Control before flying in Class C airspace.

Class D Airspace

Everything Else
Surface – 2,500ft AGL
No ATC Authorization Needed

Class D airspace consists of only one tier extending from the surface to a ceiling at around 2,500ft AGL.

During control tower hours, you need authorization to fly in Class D airspace. But outside of control tower hours, Class D airspace is no longer regulated.

Class E Airspace

Everything Else
Surface / 700ft / 1,200ft AGL – 18,000ft MSL
No ATC Authorization Needed

Class E behaves a bit differently. It effectively fills in the space between every other classification of airspace. For the most part, the floor of Class E airspace starts at 1,200ft AGL and extends all the way up to Class A airspace at 18,000ft MSL.

In the vicinity of small airports, Class E airspace can start at 700ft AGL or extend all the way down to ground level.

Quick side-note: there are two types of air traffic according to the FAA—IFR and VFR.

IFR stands for Instrument Flight Rules which apply to large aircraft that rely predominantly on computers. Any flight you’ve been on has flown under IFR.

VFR stands for Visual Flight Rules which apply to smaller aircraft in which a pilot can see and react to their surroundings while flying.

In Class E airspace, IFR traffic must communicate with Air Traffic Control, but VFR is permitted to fly freely, as long as they stay clear of any IFR traffic in the area.

Class G Airspace

Go for it!
Surface – 700ft / 1,200ft / +

Finally, this is where you fly a drone! Class G airspace is uncontrolled airspace and requires no authorization. It extends from ground level to the floor of Class E airspace at 700 or 1,200ft.

Sectional Charts

“Woah” –Most People

Sectional charts include common flight routes, runway layouts, airport radio frequencies, visual landmarks, and just about everything else a pilot could possibly need to know. They’re undoubtedly ugly and difficult to make sense of, but we’ll tackle it piece by piece and they’ll start to make sense quicker than you expect.

We’ll start by learning how to spot different classes of airspace regulation and follow with the finer details.

Fortunately, you’ll have a legend to refer to on the test, and we’ll be covering that legend and how to use it.

Reading Airspace on Sectional Charts

Whether you’re answering a question on the part 107 test or planning a day of filming, a sectional chart will be your guide to how and where airspace is regulated.

The graphic on the left is from the chart legend that you’ll have for your test.

Class B

What it looks like:
Concentric circles of solid blue lines.

How to read it:
As you know, the first tier of Class B airspace begins at the surface and continues up to a ceiling at around 10,000ft MSL. A sectional chart will define exactly how high the ceiling is like so:

This 70/SFC is telling us the Ceiling/Floor of this particular tier. With only a few exceptions, numbers on sectional charts drop two zeroes, so this is telling us that the Class B airspace immediately around Boston’s Logan Airport goes up to 7,000ft MSL.

Each new circle communicates a new tier, and with each new tier, a sectional chart provides a new ceiling/floor. In this case, we can see a new tier start with a floor of 2,000ft MSL and a ceiling of 7,000ft.

Here we have a third tier with a floor at 3,000ft MSL. Pretty simple once you know what to look for (and what to ignore!).

The airspace around Boston has some additional complexity that the FAA likes to include on the test. It’s simple. Just find the solid blue lines for the boundaries and check for the ceiling/floor notation.

Class C

What it looks like:
Concentric circles of solid magenta lines.

How to read it:
Just like with Class B airspace, we have multiple tiers with ceiling/floor notation. The crucial difference is that these altitudes are AGL (above ground level) instead of MSL (above sea level) as they were with Class B.

In this case, the first tier starts at the surface and extends to 4,300ft AGL.

The second tier of this airspace is sliced up a bit (to account for the topography of the area), so keep an eye out for the solid magenta boundaries. The FAA loves to ask tricky questions about charts like this.

Class D

What it looks like:
A single circle with a dashed blue line. (Not to be confused with the solid blue line with tick marks, which indicates the range of a radio signal.)

How to read it:
Recall that Class D airspace consists of a single tier and extends from the surface up to a ceiling at around 2,500ft AGL.

On a sectional chart, a dashed blue line indicates the boundaries of the airspace, and the number in a box defines the ceiling.

Class E (with a floor of 700ft)

What it looks like:
A shaded magenta area. 

How to read it:
The floor of Class E airspace—which is generally 1,200ft AGL—drops to 700ft AGL around small airports. On sectional charts, these areas are bordered with shaded magenta.

For example, the area around the Nauset airport in the image above is Class G airspace up to 700ft, at which point it becomes Class E airspace.

Class E (extending down to the surface)

What it looks like:
A dashed magenta line. Often shares area with a shaded magenta area.

How to read it:
Class E airspace can extend down to the surface for small airports with slightly busier runways. On sectional charts, these areas are defined with dashed magenta lines.

The example above shows the small airport just north of Acadia National Park, which can see a fairly high volume of aircraft during the summer. If you look closely at the icon in the center, you can see the arrangement of its runways. Notice how the dashed magenta lines create space for a safe approach.

Reading Airport Information on Sectional Charts

When it comes to airport information, the sectional chart legend is surprisingly helpful. If you’re familiar with a few examples, you should be good to work out any questions the FAA asks you on the test.

Once again we have the sectional chart for Boston’s Logan Airport.