Lesson 1.3

Airspace Classes C and B: Surface & Ceilings

Before every flight, it’s your job to plan ahead, scan the environment, and prepare for the unexpected. In this lesson, you’ll learn how to conduct a proper site survey, plan for emergencies, respond to in-flight issues, and land safely under pressure. These skills are what help turn an enthusiastic drone pilot into a safe, reliable, and professional one.

Class C Airspace

Requirements + Surface / Ceiling / Radius

Class C Airspace Surface / Ceiling / Radius

Class C airspace is like a tiered upside down layer cake. Class C typically consists of two concentric rings, or layers, that extend outward and upward, creating its two-tiered structure.

  • The lower shelf, which is the inner core, extends vertically from the ground up to 1,200 feet AGL, and has a radius of 5 nautical miles.
  • The outer shelf starts at 1,200 feet AGL and goes up to 4,000 feet AGL. It has a radius of 10 nautical miles.

Class B

Surface, Ceilings and Layers

Class B airspace is shaped like an upside-down wedding cake.

Class B starts at the surface near the airport and expands outward in layers as it goes higher.

This design protects large commercial aircraft as they approach and depart the nation’s busiest airports, giving them more room at higher altitudes while keeping the lower layers tightly controlled near the airport.

It is critical drone operators don’t enter Class B airspace without authorization because of how busy these airports are with manned aircraft.

Layer 1:

Layer 1 of Class B airspace is the innermost and lowest layer, shaped like a cylinder centered around the airport.

  • It usually starts at the ground-level (0 feet AGL) and extends upwards until it reaches the second, middle layer (often up to 4,000-5,000 feet AGL) .
  • This layer comprises the immediate airspace around the airport where aircraft are taking off and landing.

Layer 2:

Layer 2 of Class B airspace sits above and wider than Layer 1, forming the middle tier of the “upside-down wedding cake” shape.

  • It starts above the top of Layer 1, and extends up to around 6,000 to 8,000 feet AGL, depending on the airport’s design.
  • This layer spreads out farther horizontally to cover arriving and departing aircraft as they transition to or from cruising altitude.

Layer 3:

Layer 3 of Class B airspace is the outermost and highest layer, completing the “upside-down wedding cake” structure.

  • It typically starts at the top of Layer 2 (often around 6,000 to 8,000 feet AGL) and extends up to 10,000 feet MSL, which is the upper limit of Class B airspace.
  • This layer covers the widest area to manage aircraft that are entering or leaving the airport’s airspace from higher cruise altitudes.

Class B and C Indications on
Sectional Charts

Class C: Marked by Solid Magenta Lines
Class B: Marked by Solid Blue Lines

Class C on Sectional Charts: Solid Magenta Line

    Class C airspace is depicted on sectional charts with a solid magenta line. It typically has a cylindrical shape around the airport, but the exact boundaries are tailored to the airport’s operational needs.

    In the image below, Norfolk International Airport is identified as Class C airspace, marked by the solid magenta lines that encircle it.

    Class B on Sectional Charts: Solid Blue Line

      Class B airspace is depicted on sectional charts with a solid blue line. It typically has a cylindrical shape around the airport, but the exact boundaries are tailored to the airport’s operational needs.

      In the image below, Dallas/Ft Worth International Airport (DFW) is identified as Class B airspace, marked by the solid blue lines that encircle it.

      Practice Quiz

      Airspace Classes B and C

      1 / 7

      What type of line identifies Class B airspace on a sectional chart?

      2 / 7

      Which of the following is required before entering Class B airspace?

      3 / 7

      What specialized equipment is required to operate within Class B airspace?

      4 / 7

      Why is Class B airspace considered the most restrictive?

      5 / 7

      How is Class C airspace depicted on sectional charts?

      6 / 7

      What specialized equipment is required to operate within Class C airspace?

      7 / 7

      What communication requirement must be met before entering Class C airspace?

      Your score is

      The average score is 88%

      0%

      According to 14 CFR part 107, how may a remote pilot operate an unmanned aircraft in class C airspace?

      A. The remote pilot must have prior authorization from the Air Traffic Control (ATC) facility having jurisdiction over that airspace.

      B. The remote pilot must monitor the Air Traffic Control (ATC) frequency from launch to recovery.

      C. The remote pilot must contact the Air Traffic Control (ATC) facility after launching the unmanned aircraft

      Correct Answer: A – The remote pilot must have prior authorization from the Air Traffic Control (ATC) facility having jurisdiction over that airspace.

      Description: You will need an airspace waiver. “No person may operate a small unmanned aircraft in Class B, Class C, or Class D airspace or within the lateral boundaries of the surface area of Class E airspace designated for an airport unless that person has prior authorization from Air Traffic Control (ATC).”

      Click image to expand

      (Refer to figure 78) You have been hired to use your small UAS to inspect the railroad tracks from Blencoe (SE of Sioux City) to Onawa. Will ATC authorization be required?

      A. Yes, Onawa is in Class D airspace that is designated for an airport.

      B. No, your entire flight is in Class G airspace.

      C. Yes, you must contact the Onawa control tower to operate within 5 miles of the airport.

      Correct Answer: B – No, your entire flight is in Class G airspace.

      Description:
In this scenario, ATC (Air Traffic Control) authorization will not be required for the small sUAS inspection of the railroad tracks from Blencoe to Onawa.

      The reason is that the entire flight is planned within Class G airspace, which is uncontrolled airspace.

      Class G airspace typically extends from the surface to a specified altitude, and in this context, it allows for unmanned aircraft operations without the need for specific ATC authorization.

      Operating within Class G airspace simplifies the regulatory requirements for the flight, and as such, ATC authorization is not necessary for this particular mission.

      Click image to expand

      (Refer to Figure 20, Area 1.) The Fentress NALF Airport (NFE) is in what type of airspace?

      A. Class E.

      B. Class G

      C. Class C.

      Correct Answer: A. Class E.

      Description:
You can identify this by observing the dashed magenta line, indicating the presence of Class E airspace at the surface.