How to Read a Sectional Chart for the Part 107 Test

Sectional charts are the aeronautical maps pilots use to navigate and understand the airspace around them. They look overwhelming the first time you see one — overlapping circles, numbers everywhere, colors and symbols that do not mean anything until someone explains them. This guide walks through everything you need to know to read one for the Part 107 exam.

The best way to practice is to pull up a real chart. The FAA publishes current sectional charts for free at SkyVector. Open it in another tab and follow along as you read this.

What Is a Sectional Chart?

A sectional aeronautical chart is a 1:500,000 scale map of the airspace over a specific region of the US. The name comes from the fact that the country is divided into sections, each covered by its own chart. They show airports, airspace boundaries, terrain elevation, obstacles like towers and antennas, and navigation aids.

For drone pilots, the most important things on a sectional chart are airspace class boundaries, airport locations and types, obstacle heights, and the numbers around airports that tell you the ceiling and radius of controlled airspace.

Airspace: Colors and Lines

The first thing to learn is how each airspace class is depicted. This is what you will use to determine whether you need authorization before flying somewhere.

Airspace Class	How It Looks on the Chart	Need Authorization?
Class B	Solid blue lines forming concentric rings, like an upside-down wedding cake when viewed in cross-section. The area is shaded blue.	Yes
Class C	Solid magenta circles, typically two rings — an inner and outer ring around the airport.	Yes
Class D	Dashed blue circle around the airport.	Yes
Class E to surface	Dashed magenta circle. This is the one people miss. It looks similar to Class D but is magenta instead of blue.	Yes
Class E at 700 ft AGL	Solid magenta shading that fades outward from an airport. Where the shading is, Class E starts at 700 feet AGL.	No (floor is above 400 ft)
Class G	Everything not shaded or circled. The absence of markings means Class G.	No

Reading the Numbers Around an Airport

Near controlled airports you will see a set of numbers that look something like this:

Here is what each line means:

Number/Label	What It Means
Top number (e.g. 110)	The ceiling of the airspace in hundreds of feet MSL. So 110 means the airspace goes up to 11,000 feet MSL.
Bottom label (e.g. SFC)	The floor of the airspace. SFC means the airspace starts at the surface. You might also see a number here like 20, which would mean 2,000 feet MSL.
Radius (e.g. 4 NM)	The horizontal radius of that ring of airspace in nautical miles from the airport.

For Class B airspace with multiple rings, each ring has its own set of numbers showing the ceiling and floor for that specific tier. The inner rings typically go from the surface up. Outer rings often have higher floors because the airspace steps up as you move away from the airport.

Airport Symbols

The type of airport symbol on the chart tells you what services and airspace you can expect:

Symbol Type	What It Means
Solid blue circle with runway lines	Airport with a control tower. Likely Class C or D airspace. Requires authorization.
Solid magenta circle with runway lines	Airport without a control tower. Likely Class E or G airspace depending on other markings.
Circle only (no runway lines)	Private or seaplane base.
Star symbol	Airport with rotating beacon, meaning it operates at night.

Obstacle Symbols and Heights

Tall structures like towers, antennas, and wind turbines are marked on sectional charts. Each one shows two numbers stacked on top of each other:

Number Position	What It Means
Top number (bold)	Height of the obstacle in feet MSL (above mean sea level)
Bottom number (in parentheses)	Height of the obstacle in feet AGL (above ground level)

Example: You see a tower symbol with 1,245 on top and (328) below. That tower reaches 1,245 feet MSL and sticks 328 feet above the ground. If you are flying in an area where the terrain is at 900 feet MSL, that tower only clears the local ground by about 345 feet.

The exam will sometimes ask you to figure out whether an obstacle creates a conflict for a planned flight altitude. Always check whether the height given is MSL or AGL and convert if needed.

Other Markings Worth Knowing

Marking	What It Means
Blue shaded areas	Class B airspace
R followed by a number (e.g. R-2301)	Restricted area. Flight may be limited or prohibited depending on whether the area is active.
P followed by a number (e.g. P-40)	Prohibited area. No flight allowed at any time.
MOA label	Military Operations Area. Not prohibited for civilian aircraft but be aware of military activity.
Contour lines and shading	Terrain elevation. Darker shading usually means higher terrain.
VOR symbol (compass rose)	VHF Omnidirectional Range navigation station. Less relevant for drones but shows up on charts.

How the Exam Uses Sectional Charts

The Part 107 exam will show you a cropped section of a real sectional chart and ask questions about it. Common question types:

• What class of airspace is a specific location in?
• What is the ceiling of the controlled airspace in a given area?
• Does a planned flight altitude conflict with an obstacle's height?
• Is authorization required to fly at a specific location?
• What does a specific symbol on the chart represent?

The best preparation is time on real charts. Open SkyVector, find the area around your nearest airport, and start identifying airspace classes, reading the numbers, and locating obstacles. Twenty minutes of that is worth more than an hour of reading about it.

A Quick Exam Checklist for Any Sectional Question

• What color are the lines or shading near the location in question?
• Is the circle dashed or solid? Blue or magenta?
• What do the ceiling and floor numbers say for that airspace ring?
• Are there any obstacle symbols nearby and what are their heights?
• Are there any restricted, prohibited, or MOA areas in the question?

---