Understanding airspace can be really difficult for drone pilots, typically because you are someone who is unfamiliar with aviation to begin with. If you have not already, you will quickly become familiar with a flight planning map called a Visual Flight Rules (VFR) sectional. Everyone just refers to these maps as sectionals. The sectional indicates airspace classifications along with a multitude of other helpful markers. All markings on the sectional are measured in height above mean sea level, unless they state otherwise. To familiarize yourself with a sectional chart and its markings, your time will be best spent reviewing a sectional legend. Another place to get sectionals to review and learn about individual markings is vfrmap.com (it’s free). This will allow you to see any part of the United States and to become familiar with the map. Additionally though, it will ultimately be helpful to zoom in on your local area and get a better idea of the surrounding airports near you.
The best advice I can give you is actually to open a sectional in one browser window and a sectional legend in another window. Place them side by side and look at the markings. Chances are, after some practice, you will be able to identify most of them. If there’s something you’re struggling with, feel free to contact me (my email is listed on the About page). I’ll either send you an answer to your question or create a post answering the question.
Recognizing Airspace 101
Controlled vs. Uncontrolled Airspace
The key to airspace classification for drone pilots is to know that all airspace in the United States is either controlled or uncontrolled. Classes A, B, C, D, and E are controlled. Class G is uncontrolled. We will discuss each of these below except Class A because it is generally 18,000 MSL and above and really doesn’t apply to what we’re learning about here. If you’re flying at 18,000 feet, you’ve got way cooler drones than I do and probably already have some pretty sick training on how to fly them.
To start out, just know that you will always need permission to fly in controlled airspace. Once you have your Part 107 license, you have permission to fly drones for commercial purposes in the U.S. but will still need additional permission to fly in controlled airspace. Check out the first section on getting Part 107 waivers if you haven’t already or our article on the difference between a Part 107 authorization and a waiver.
What is Class B Airspace?
Class B airspace surrounds the nation’s busiest airports (think B for busy) and is indicated by a solid blue line on a sectional. It looks a lot like a 3-tiered upside down wedding cake overtop of the airport (see below). The smallest section of the cake is typically a 5-mile radius containing the main portion of the airspace from the surface to 10,000 ft MSL plus two outer shelves. Each outer shelf encompasses a larger swath of land but does not reach down to the surface at the edges.
If you look at the figure below, the airspace surrounding CVG (Cincinnati International Airport), you can see the markings on the map showing 100 over SFC, 100 over 21, 100 over 35, and 100 over 50. I’ve added red squares over these markings on the image below, but please note that these markings are not usually covered in red on a sectional. I just did this to call your attention to it. The last two zeros of the altitude will be cut off, but 100 over 21 indicates that Class B airspace in this area extends from 2,100 feet MSL to 10,000 feet MSL. It is the same reading with each of the rest of these notations. The top number indicates the top of the airspace and the bottom number indicates the floor of the airspace. SFC as the bottom “number” means surface, and is usually reserved for the top tier of the “wedding cake,” which is the circle closest to the airport.
What is Class C Airspace?
Class C airspace is typically less busy than Class B airspace and is indicated on a sectional by a solid magenta line. These airports still have a control tower and radar controlled approach. Like Class B airspace, Class C airspace also has an upper shelf (think upside down wedding cake again. Only this time it is a 2-tiered cake).
Class C only has one shelf instead of the two associated with Class B. Class C airspace is usually from the surface to 4,000 MSL, which is again different than Class B in that it does not extend as high (Class B is typically 10,000 MSL). Despite the fact that you will likely never be flying your drone at or above 4,000 MSL, this will be important information to know and understand for purposes of getting your license. Although the size and shape of Class C airspace can be (and usually is) tailored to the specific airport, the bottom layer of the cake usually has a 5 nautical mile radius, just like Class B, with the shelves extending outwards from there.
Below, you can see that the bottom later of the cake shows that Lexington, Kentucky’s airport has Class C airspace extending from the surface up to 5,000 MSL. Note that this is a departure from the normal 4,000 foot MSL ceiling of typical Class C. The outer shelf extends from 2,200 feet MSL to 5,000 feet MSL. Additionally, the numbers in magenta (50 over SFC and 50 over 22) indicate the floor and ceiling of the airspace just like Class B above.
What is Class D Airspace?
Class D airspace is typically surrounding an airport with a control tower, although it is, yet again, less busy than airports with Classes B and C airspace. It is indicated on a sectional chart by a dashed blue line. It typically extends from the surface to 2,500 feet MSL and is also tailored to the airport, containing all approaches and procedures. Class D airspace is indicated by a dashed blue line on a sectional. Although you can also use the wedding cake analogy here, it would simply be a one layer cake, as Class D airspace does not have shelves like Classes B and C.
Below is Cincinnati, with its international airport, as discussed above, as well as Lunken airport off to the east. Within the dashed blue line surrounding Lunken Airport is the number 30 within four brackets, like this: 
. This indicates that the top of the Class D airspace is 3,000 feet MSL. Note that this is a departure from the normal top altitude for Class D airspace of 2,500 feet MSL. I realize that Lunken doesn’t exactly stand out in this part of the sectional, but sometimes airspace indications are like that, and I think this is a good primer for the test.
What is Class E Airspace?
Class E airspace is the most common type of airspace in the United States but is easily misunderstood because it has two main variations: Transitional and Enroute. Second, Class E airspace is different because it is measured in feet above ground level (AGL) instead of mean sea level (MSL) like all other airspace. I said it above, but it bears repeating here: When dealing with altitude on a sectional, you are looking at MSL. Class E is the exception to this rule.
Transitional Class E airspace generally shows up around airports and is identified on a sectional as a faded magenta ring. This ring indicates that class E airspace begins at 700 feet AGL, extending upward. Additionally, sometimes airports with a faded magenta ring will also have a dashed magenta line around them. This indicates that Class E airspace extends down to the ground within this circle. The picture below is a great example of both. Boone airport to the west is surrounded by Class E airspace that begins at 700 feet AGL. Ames airport to the east not only has Class E airspace from 700 feet above ground level within the faded magenta ring, but it also has Class E airspace to the ground within the dashed magenta circle.
Enroute Class E airspace is from 1,200 ft AGL to 18,000 feet AGL and is not associated with airports, but it is associated with what are called Victor airways. You should be familiar with enroute Class E airspace for purposes of the test, but recognize that you will likely never be flying your drone at 1,200 feet AGL and, thus, will not need to worry about it when flying unmanned aircraft for commercial purposes.
To be clear, there are places where Class E airspace does not begin until 14,500 and these are typically understood on a sectional chart just by the absence of a Class E floor on the chart of 700 or 1,200 feet AGL. Finally, there is Class E airspace above 60,000 feet MSL, but ,again, this will not apply to you for purposes of the Part 107 exam.
What is Class G Airspace?
Remember how I said that the key to airspace classification for drone pilots is controlled vs. uncontrolled? Class G airspace is the only form of uncontrolled airspace in the United States. Because it is uncontrolled, recognizing Class G airspace is different than recognizing any other airspace. It is not marked on a sectional, but instead can be understood as not being Classes A, B, C, D and E. We have not discussed Class A airspace, but this is unnecessary for purposes of the Part 107 knowledge exam because Class A airspace in the United States begins at 18,000 feet MSL and goes until 60,000 feet MSL. Obviously, it is not implicated in flying small unmanned aircraft. Remember, Class G airspace is uncontrolled, and once you have your Part 107 license, you are able to legally fly here for commercial purposes without additional approval.
While this covers airspace classification for drone pilots, it is also important to understand special use airspace, which we will cover in the next section.
Special Use Airspace for Drone Pilots
We’ve covered airspace classifications in the last section and while I wish I could say that this is all you need to know about airspace, it’s not. Another important part of airspace is understanding the use of drones in special use airspace.
Special use airspace is exactly what is sounds like: Airspace that is marked off for a specific and special type of use. Flying drones in special use airspace depending wholly on the type of special use airspace, which we will discuss below.
Usually, it involves something that could be hazardous to air traffic, or other times it involves issues of national security. The FAA even has a “No Drone Zone” campaign that includes flying drones in special use airspace. No matter what the special use, it is important to know if you can fly there legally.
Prohibited Areas
Prohibited areas are identified on a sectional by a solid blue line with lines extending inward and charted as “P” followed by a number. These areas prohibit all flight of aircraft for national security reasons. Naturally, drone flight is also prohibited here. A prohibited area is pictured below.
Restricted Areas
Restricted areas are also identified on a Sectional by a solid blue line with perpendicular lines extending inward and charted with the letter “R” followed by a number. These areas are usually restricted because of activity that would be hazardous to an aircraft like artillery firing, guided missile testing, or some other hazard to aircraft. You must have permission to fly through a restricted area. A restricted area is pictured below.
Warning Areas
Warning areas are also identified on a sectional by a solid blue line with lines extending inward and charted with the letter “W” followed by a number. They are similar to restricted areas but with the understanding that the United States does not have sole jurisdiction over the airspace. Many times this will show up along the coast and may encompass both domestic and international waters. A warning zone is pictured below.
Military Operation Areas (MOAs)
These areas are identified on a sectional by a solid magenta line with perpendicular lines extending inward and charted with the name of the area follow by “MOA.” These areas are blocks of airspace where military maneuvers are conducted. You must exercise extreme caution in these areas when military activity is being conducted. Although you are not restricted from flying here, it is wise to avoid an MOA when possible. The other thing about MOA’s is that they don’t operate all the time. The sectional chart typically has information off to the side showing the active hours of the MOA. Check the legend and the side of the sectional chart to determine the operating times of the MOA.
A military operating area is pictured below.
Alert Areas
Alert areas are also identified on a sectional by a solid magenta line with perpendicular lines extending inward and charted with the letter “A” followed by a number. These areas depict an unusually high volume of pilot training or an unusual type of aerial activity such as parachute jumping, glider towing, or high concentrations of student pilot training. Any flights in these areas should be maintained with extreme caution. An alert area is pictured below.
Controlled Firing Areas (CFAs)
These areas are set up so that people (both public and private) can blow things up. While you should be aware that these areas exist, in the real world these areas aren’t on a sectional chart, nor do they show up in NOTAMs (see below). In addition, there’s no one to contact. In fact, you will probably never know when you are flying in one, unless you spot the explosion. Instead, these areas are set up so that the activity being conducted stops if/when the user spots an aircraft. Also, just to be clear, this type of area would not include shooting explosives from an aircraft, but are typically just for static rockets tests or disposal of explosives.
Knowing when you can fly drones in special use airspace is a key part of the Part 107 exam. With a little practice, you will know and understand the differences. On to NOTAMS as well as any remaining airspace issues.
Other Airspace Issues
I know, I know, you’re tired of airspace, but this is the last section, and it sort of wraps up other airspace issues for drone pilots that weren’t covered previously.
Notice to Airmen (NOTAMs) for Drone Pilots
One of the other airspace issues for drone pilots that we will cover here is NOTAMs. Drones and NOTAMs used to go hand in hand. Under the previous rules, drone pilots were required to file NOTAMS before flights. But no more! No matter, you should still understand what a NOTAM is because it provides useful information to commercial drone pilots prior to a flight (not to mention, it is on the test).
These notices provide time-critical aeronautical information that is either temporary or not known in advance to permit publication on aeronautical charts or airport/facility directory. These hazards can be anything from an air show to inoperable lights on tall obstructions or (my personal favorite) a flock of birds going through airspace (called a BIRDTAM). Your best bet before a flight is to check a flight map like Airmap (they have an app that works really well too). A recent search before a flight even indicated to me the existence of an emergency, which appeared to be an ambulance or other type of emergency vehicle. While NOTAMS include a lot of things that apply only to manned pilots, like approach procedures at airports or lights that are out on approach, Airmap appears to sift through these to provide only what is important for drone pilots.
The FAA provides a site called PilotWeb to retrieve NOTAMs but, to be honest, these can be a bit difficult to decipher and doing so is not included on the Part 107 knowledge exam. Prior to Part 107, commercial drone pilots were required to file a NOTAM before flying. This requirement was removed with Part 107 because the FAA felt that it would just clutter the NOTAM system for manned pilots without adding any real level of security.
Temporary Flight Restrictions (TFRs)
By far the most important part of this section on other airspace issues for drone pilots deals with TFRs, so listen up!
A TFR is issued by a flight data center through a Notice to Airmen (NOTAM) and will always begin with the words “FLIGHT RESTRICTIONS.” It will also indicate the location of the restriction, time period, area in statute miles, and the altitudes affected. These will also show up on a flight map like Airmap.
A TFR can be issued for a multitude of reasons, but is typically in place to:
- Provide safety for the operation of disaster relief aircraft;
- Prevent congestion of aircraft above or around an event that might generate a lot of public interest (i.e., sporting events); or
- Protect the President, Vice President, or other public figures.
As a drone pilot, it is your responsibility to know if/when a TFR is in place and to avoid those areas.
Miscellaneous Airspace Areas
There are a number of miscellaneous airspace areas that are categorized by the FAA. While these tend to be less prevalent and less applicable for our purposes here, they show up in the FAA Part 107 Study Guide, so we’ll talk about them briefly.
Local Airport Advisories (LAA)
This is an advisory service that is provided by flight services facilities for airports that have a part-time tower. The advisory is broadcast on a radio frequency and can include things like weather reporting, airport advisories, or other automated instrument readings.
Military Training Route (MTR)
Military training routes are exactly what they sound like. Military pilots need to make sure that they stay proficient in tactical flying and these training routes are maintained for that purpose. These are identified as either IR (an indication that they are used with instrument flight rules) or VR (which indicates they are used with visual flight rules. The IR or VR is then followed by a number, which is either 3 or 4 digits long. If there are 3 digits, this means that at least part of the route is above 1,500 feet AGL. If there are 4 digits, this means that none of the route goes higher than 1,500 feet AGL.
To help picture this, the image below shows an IFR military training route (in the red circle) called IR720. This means that the training route uses instrument flight rules and has some segments that are above 1,500 feet AGL.
Parachute Jump Aircraft Operations
These are published in the Chart Supplement U.S. and places where parachute jumping is a frequent activity and will include this symbol 
on the sectional chart. Just do yourself a favor and stay away from anywhere that you know parachute activity is occurring.
Published VFR Routes
Sometimes when smaller aircraft are looking to fly near busy airspace (think Class B airports) they would prefer to stay far away from larger aircraft, specifically those with jet engines. Published VFR routes, which are also called VFR flyways or VFR corridors, provide specific routes for these planes to fly. They are published on an aviation chart called a VFR terminal area planning charts, or VFR TACs.
Terminal Radar Service Areas (TRSA)
A TRSA is an odd type of airspace. Even though it is not controlled, this is an area that has radar and air traffic control services. While communication with air traffic control within this type of airspace is optional for VFR pilots, it is recommended, as it is usually utilized to keep the flow of air traffic coordinated and separated. Again, while not controlled, you can see it depicted in the picture below as a grey box and the numbers in those grey boxed areas indicate the altitudes of the floor and ceiling of those areas, just like they do for Classes B and C.
National Security Areas (NSA)
These areas are just what they sound like: areas on the ground that, for whatever reason, require additional security and safety on the ground. Flying over these areas can be prohibited and, if it is, that prohibition will be communicated in a NOTAM. The FAA requests that pilots voluntarily avoid flying through these areas. You’d be wise as a drone pilot to do the same.
Air Defense Identification Zones (ADIZ) and Defense VFR (DVFR)
An Air Defense Identification Zone is over an area where civil aircraft is controlled for the interest of national security. Most notably, there is an ADIZ over Washington, D.C.
Flight Restricted Zones (FRZ) in the Vicinity of the Capitol and White House
As you can imagine, flying in and near Washington D.C. is highly restricted. The FRZ is a 13-15 nautical mile area surrounding the D.C. area, which restricts aircraft movement to very specific flights. It is possible to get a waiver to fly within the Flight Restricted Zone (FRZ) around D.C., but I can imagine it is difficult to obtain. Just don’t fly here unless you have a waiver. And even then, do so very carefully and within the confines of your waiver.
Wildlife Areas, Wilderness Areas and National Parks
Superintendents of the National Parks System have the authority to prohibit the launching, landing or operation of unmanned aircraft under Policy Memorandum 14-05. Because drone use must be done within the line of sight of the remote pilot, this automatically excludes flights in a lot of national parks, which was probably the idea when the policy was handed down. I guess there have been issues, including one incident where a drone was landed on Lincoln’s head at Mount Rushmore.
Additionally the Aeronautical Information Manual (AIM) states:
Pilots are requested to maintain a minimum altitude of 2,000 feet above the surface of the following: National Parks, Monuments, Seashores, Lakeshores, recreation Areas and Scenic Riverways administered by the National Park Service, National Wildlife Refuges, Big Game Refuges, Game Ranges and Wildlife Ranges administered by the U.S. Fish and Wildlife Service, and Wilderness and Primitive areas administered by the U.S. Forest Service.
While the AIM is simply for guidance and this rule only “requests” that pilots stay above 2,000 feet AGL, you should just stay away from these designated areas altogether.
If you’re looking for more information on flying your drone in these areas, I’ve got a whole article discussing drone flight in National Parks.
Tethered Balloons for Observation and Weather Recordings that Extend on Cables up to 60,000 feet
My first thought on seeing this as a topic for the test is that is seems ridiculous that there are balloons on tether cables going up to 60,000 feet. But I guess they exist and presumably for good weather-related reasons. But it didn’t take long to confirm my suspicion that a plane had actually run into a balloon tether. To be clear though, the balloon was in a restricted area, and this is typically the case with these balloons for this exact reason.
Now, we are officially done with airspace and have sufficiently covered flying drones in other airspace areas. Let’s move on to airports.
