FAR 103.11 — Ultralight Daylight Operations
FAR 103.11 limits ultralight vehicle operations to daylight hours, with limited twilight exceptions. Learn the rule, lighting, and airspace requirements.
FAR 103.11 governs when you can legally fly an ultralight vehicle. The general rule is simple: ultralights may only be operated between sunrise and sunset.
There is a narrow exception for twilight operations. You may fly during the twilight window if every condition below is met:
- The window is 30 minutes before official sunrise to 30 minutes after official sunset (in Alaska, the period of civil twilight as defined in the Air Almanac applies instead).
- The ultralight is equipped with an operating anticollision light visible for at least 3 statute miles.
- All operations are conducted in uncontrolled airspace.
Why it matters operationally: ultralights are unregistered, uncertificated, and flown by unlicensed operators under Part 103, so the FAA limits them to conditions where see-and-avoid works well. Flying after dark, into controlled airspace at twilight, or without a proper anticollision light puts you outside Part 103 and exposes you to enforcement action.