Why Is the Airport’s Rotating Beacon on When It’s Daylight?

Sometimes the big light goes around because conditions are below VFR minimums.

Meg Godlewski

Wednesday, May 28, 2025 at 09:00 AM ET

Verified

Edited By:

Travis Tingle

One of the old rotating beacons on the ground at South Lewis County Airport (KTDO) in Toledo, Washington. [Courtesy: Meg Godlewski]

Key Takeaways:

Airport beacons are primarily illuminated at night to help pilots locate the airport.
If an airport beacon is on during the day, it generally indicates that the weather conditions are below Visual Flight Rules (VFR) minimums or that maintenance testing is being performed.
Historically, beacons served as important navigation aids for pilots before the widespread use of radios.

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Question: I just attended an aviation event that spanned a weekend. The airport has a control tower. On Friday and Saturday the airport beacon was on during the day. It was turned off on Sunday. I thought the beacon is only on at night?

Answer: The rotating beacon is on at night to help pilots find the airport. When it is on during the day, it is usually because the weather at the airport is below VFR minimums. It can also be turned during the day in VFR conditions when maintenance has been performed on the light and the technicians need to test it.