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Class D airspace for drone pilots

Last updated 2026-11-14 · Published by Certloom Learning · Sources

Class D is the dashed blue airspace around an airport with an operating control tower, generally from the surface to 2,500 ft above the airport elevation. 14 CFR 107.41 requires prior ATC authorization for a Part 107 flight there, and part-time towers change what applies after hours.

What is Class D airspace?

The AIM says Class D generally extends from the surface to 2,500 ft above the airport elevation (charted in MSL) around airports that have an operating control tower. The shape is custom: where instrument procedures are published, the area is normally designed to contain them. The AIM also says no separation services are provided to VFR aircraft in Class D, which is worth knowing because it explains why it is a smaller, simpler form of controlled airspace than B and C.

The study guide gives the remote pilot one sentence to remember: you must receive ATC authorization before operating in Class D.

Sources (checked 2026-11-14): AIM 3-2: Controlled Airspace; FAA Remote Pilot sUAS Study Guide (FAA-G-8082-22).

How does Class D look on a sectional chart?

The Chart Users' Guide says Class D is identified with a blue dashed line, and the AIM adds that it is shown with blue segmented lines on sectional and terminal charts. Inside the circle, a number in a dashed blue box gives the ceiling in hundreds of feet MSL. A minus sign in front of the number means the Class D runs from the surface up to, but not including, that altitude, usually because other airspace begins above it.

LabelReads as
[25] in a dashed blue boxSurface to 2,500 ft MSL
[36]Surface to 3,600 ft MSL
[-30]Surface up to, but not including, 3,000 ft MSL

On the Corpus Christi chart (Figure 69), a dashed blue box with 25 marks the Kingsville Naval Air Station Class D. Its data block shows field elevation 50 ft MSL and a tower with a star, meaning part-time. 2,500 ft above a 50 ft field is 2,550 ft, charted as 25 in hundreds of feet MSL. On the Norfolk chart (Figure 20), Elizabeth City and Newport News/Williamsburg are the dashed blue examples. Open the Corpus Christi lesson to tap them.

Sources (checked 2026-11-14): FAA Aeronautical Chart Users' Guide (effective 9 July 2026); AIM 3-2: Controlled Airspace.

How do I convert a Class D ceiling to feet AGL?

Subtract the ground elevation from the MSL ceiling. Because the ceiling is built from the airport elevation, the ceiling AGL is usually about 2,500 ft right at the airport and changes as the ground rises or falls around it.

Worked example

Ceiling and your altitude

Say an airport sits at 1,100 ft MSL. Class D tops out near 3,600 ft MSL, charted as 36.

For a Part 107 flight, the ceiling rarely matters. A drone at 400 ft AGL or below is almost always under it, so the question is lateral: inside the dashed circle or outside.

The ceiling does matter in two cases: you fly up a tall structure's side within 400 ft of it, or you are on a steep mountain edge. In those cases do the same subtraction before deciding.

What happens when the tower closes?

Many Class D airports have part-time towers. A star next to the tower frequency on the chart marks a part-time tower, and a note such as "See NOTAMs/Directory for Class D eff hrs" points you to the Chart Supplement. The AIM says part-time Class D effective times are published in the Chart Supplement. When the tower is closed, the surface area may revert to either a Class E surface area or Class G, and the airport entry in the Chart Supplement says which, with wording like "other times CLASS E" or "other times CLASS G".

The Chart Supplement also warns that arrival extensions follow the surface area: if the surface area reverts to Class G, the extensions do too, and if it reverts to Class E, the extensions stay Class E. LAANC and the FAA's UAS Facility Maps handle this for you, but the knowledge test can ask about it. Read more in reading the Chart Supplement.

Sources (checked 2026-11-14): AIM 3-2: Controlled Airspace; FAA Aeronautical Chart Users' Guide (effective 9 July 2026).

What is a sensible order of checks before a Class D flight?

  1. Find the dashed blue circle and see whether your site is inside it.
  2. Look at the airport data block. A tower frequency with a star means a part-time tower. Blue type marks a towered airport.
  3. If the tower is part time, open the Chart Supplement entry for the airport and read the airspace line for the hours and for what applies at other times.
  4. Convert the UTC hours to local time for the day of your flight, including daylight saving time.
  5. Request the authorization for the hours when the airspace is Class D or Class E surface area. If it is Class G at your flight time, no 107.41 authorization applies, but keep to the other Part 107 rules.

Apps do this check for you, but a person who understands why the answer changes after hours is less likely to approve the wrong time slot.

What does a Part 107 pilot need to fly in Class D?

Prior ATC authorization under 14 CFR 107.41. The AIM requires manned aircraft to establish two-way radio contact with the tower before entry and says there is a 200 knot speed limit within 4 NM of the primary airport at or below 2,500 ft above the surface. Those are not your rules. You request the authorization in LAANC or FAADroneZone.

Part 107 gives you two routes to the authorization. LAANC works through an FAA-approved service supplier's app and usually answers in near real time when you ask for an altitude at or below the UAS Facility Map value for that spot. If you need more than the map allows, you can send a further coordination request for up to 400 ft AGL; the FAA asks for these at least 72 hours before the flight, and you can file up to 90 days ahead. Airports that are not LAANC-enabled go through FAADroneZone instead, where the FAA says processing historically takes up to eight weeks. Unless the authorization says otherwise, you do not call the tower before you fly.

Sources (checked 2026-11-14): FAA: Part 107 Airspace Authorizations; FAA: UAS Data Exchange (LAANC).

Separately, 14 CFR 107.43 forbids operating in a way that interferes with operations and traffic patterns at any airport, heliport or seaplane base. An authorization to fly in the airspace does not excuse you from yielding to manned aircraft under 107.37.

How does Class D relate to Class C, Class E and Class G?

Class D has no shelves of its own. It is a single column around a towered airport without the bigger layered structure of B or C. Overhead and around it, controlled airspace continues as Class E, and where the tower is closed it may fall back to Class E or G as above. A Class D that sits beneath a Class B or C shelf may be charted with a minus ceiling. The AIM also notes that surface area arrival extensions for instrument approaches may be Class D or Class E. As a general rule, if all extensions are 2 miles or less they remain part of the Class D surface area, but if any one is longer than 2 miles, all the extensions are Class E. In both cases they belong to the surface area and follow its hours, so a narrow strip reaching out from the circle is still airspace you must check. See Class C for the next step up and Class E for surface areas and the blue and magenta vignettes.

Sources (checked 2026-11-14): FAA Aeronautical Chart Users' Guide (effective 9 July 2026); AIM 3-2: Controlled Airspace.

What are the common test traps for Class D?

Free practice questions on this topic

3 original questions from the Sectional Cue bank. Try each one, then open the answer.

Class D ceiling
1. In Figure 69, a remote pilot has authorization to fly in the Kingsville NAS (NQI) Class D near area 2 while the tower operates. Per the dashed blue box with 25, what is the top of that Class D? (uses Figure 69, open the free chart lesson)

  1. 2,500 ft AGL
  2. 2,500 ft MSL
  3. 8,000 ft MSL
Show answer and explanation

B. 2,500 ft MSL

The number in the dashed blue box is the Class D ceiling in hundreds of feet MSL, so 25 means 2,500 ft MSL. Class D ceilings are not charted in AGL. 80 in the data block (*L 80) is the longest runway, 8,000 ft, not an altitude.

Source: FAA-CT-8080-2H, Figure 69; Chart Users' Guide; 14 CFR 107.41

Part-time tower
2. In Figure 20, the Newport News/Williamsburg Intl (PHF) data block shows CT - 118.7 followed by a star and a C in a circle. What does the star tell a remote pilot? (uses Figure 20, open the free chart lesson)

  1. The tower operates part-time, and 118.7 serves as the CTAF when the tower is closed
  2. The airport has a rotating beacon that operates only at night
  3. The airport is surrounded by Class C airspace
Show answer and explanation

A. The tower operates part-time, and 118.7 serves as the CTAF when the tower is closed

On the sectional legend a star after the tower frequency means the tower is part-time, and the C in a circle marks that frequency as the CTAF when the tower is closed. A rotating beacon is a separate star symbol drawn on the airport symbol itself, not after CT. The airspace here is Class D, shown by dashed blue lines, not Class C.

Source: FAA-CT-8080-2H, Figure 20; Legend 1; Chart Users' Guide

Part-time Class D hours
3. In Figure 69, the note See NOTAMs/Directory for Class D eff hrs appears near Cabaniss NOLF (NGW). Where should a remote pilot check when that Class D is in effect? (uses Figure 69, open the free chart lesson)

  1. In the sectional chart legend
  2. In NOTAMs and the Chart Supplement
  3. On the nearest airport's AWOS broadcast
Show answer and explanation

B. In NOTAMs and the Chart Supplement

The note means the Class D is part time, and its effective hours are published in the Chart Supplement (formerly the Airport/Facility Directory) and changes appear by NOTAM. The chart legend explains symbols but not hours. An AWOS broadcasts weather, not airspace hours.

Source: FAA-CT-8080-2H, Figure 69; Chart Users' Guide; 14 CFR 107.41

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Sources

How this page was made: written by Certloom Learning from the sources above, with the rules checked against the current regulation text. Practice items are original questions from the app's reviewed bank. Spot an error? certloomlearning@gmail.com.