Airspace

What is Class D Airspace?

Class D airspace surrounds smaller airports with operational control towers — typically a 4–5 nautical mile cylinder from the surface to 2,500 ft AGL. Drones require LAANC authorization in Class D.

Class D is the smallest of the towered controlled airspace classes. It's a single cylinder, usually 4–5 nautical miles in radius, extending from the surface to 2,500 ft AGL (the exact ceiling varies by airport). Class D exists only when the tower is operational; outside tower hours, the airspace typically reverts to Class E or G.

Drone operations in Class D require LAANC. Per-cell ceilings tend to be more permissive than Class B and C — many cells offer 200–400 ft AGL automatic approval — but cells directly over the runway are 0 ft AGL.

Class D is depicted on sectionals as a dashed blue line.

What this means for pilots

Class D fields are common in suburbs (Northeast Philadelphia PNE, Centennial APA in Denver, Hayward HWD). LAANC ceilings are usually friendly. The dashed-line indicator on sectionals helps distinguish Class D from Class C and B.

FAQ

Does Class D apply at night when the tower is closed?

No. Class D is only active when the tower is operational. Outside hours, the airspace becomes Class E or G — usually still requiring LAANC if Class E surface area, or no authorization needed if Class G.

Can I fly without LAANC in inactive Class D?

Only if the airspace reverts to Class G when the tower closes. Many Class D airports revert to Class E surface area, which still requires LAANC.

How tall is Class D typically?

Up to 2,500 ft AGL is most common; some airports cap at 2,000 ft. The exact figure is on the sectional chart.

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FAA regulations change. Verify current rules at faa.gov/uas before relying on this article for flight planning. Altoa is not the FAA.