The headline rule. Under 14 CFR Part 107, UAS operators are required to obtain prior authorization before operating in any controlled airspace (Classes B, C, D, and the surface-area portions of Class E around airports).

• Exception — non-surface Class E airspace (the far-from-airports kind).
• How to get authorization — FAA’s LAANC (Low Altitude Authorization and Notification Capability) system, typically via apps like Aloft or Airmap. Some airports still require a manual DroneZone request.