Rock Your Wings and Watch for Light - ATC Light Gun Signals, No-Radio Ops, and Ninety-One One Twenty-Five at Oshkosh

If your radio quits while you’re flying to or from a towered airport in good daylight, it’s an inconvenience - not an emergency. Under FAR 91.125, the tower can direct you with a high-intensity light gun, using seven color-coded signals. Squawk 7600, fly where the controllers can see you, watch the tower cab for light, and acknowledge by rocking your wings.

What does FAR 91.125 say about ATC light signals?

FAR 91.125, titled ATC light signals, covers what happens when you’re operating at an airport with an operating control tower and can’t use the radio. The controller aims a focused, high-intensity colored beam directly at your airplane, and that beam becomes your clearance.

It’s one of the most quietly reassuring paragraphs in the regulations. You don’t actually need a working radio to operate in controlled airspace - you need a way to receive instructions. If the radio is gone, the tower still has a way to reach you: a light.

How do I memorize the seven light gun signals?

Don’t memorize a chart. Learn the logic, and the chart builds itself.

Colors first. Green means go, good, or cleared. Red means stop, no, or give way. It’s the same as a street traffic light, and your brain already knows it.

Steady vs. flashing next. A steady light is about right now. A flashing light is about not yet or a change.

Put those two ideas together and every signal falls into place.

Signals when you’re in the air

• Steady green - Cleared to land. Green is good, steady is right now.
• Flashing green - Return for landing. You’re welcome, but it’s not your turn yet; expect a steady green when it is.
• Steady red - Give way to other aircraft and continue circling. Someone else has the runway.
• Flashing red - Airport unsafe, do not land. This is the one that should raise the hair on your neck.
• Flashing white - Not used in the air. Set it aside.

Signals when you’re on the ground

You are far more likely to actually see a light gun while taxiing than while flying.

• Steady green - Cleared to taxi.
• Flashing green - Cleared to taxi (cleared to move from a hold).
• Steady red - Stop right where you are.
• Flashing red - Taxi clear of the runway in use.
• Flashing white - Return to your starting point on the airport (the ramp or parking spot).
• Alternating red and green - Exercise extreme caution. It doesn’t say stop or go; it’s the controller telling you to pay attention because something’s going on.

Said all at once: Green is good, red is stop, and white sends you home. Steady is right now, flashing is not yet or a change. Alternating red and green means be careful.

What do I actually do if my radio fails?

A lost radio by itself, in good weather and daylight, is an inconvenience, not a crisis. The airplane still flies, you still have eyes, and the tower still has that light. Slow your brain down and work the problem.

1. Squawk 7600 on the transponder. That code tells everyone your radio is out.
2. Fly toward the airport and get where the tower can see you.
3. Look for the light. A light gun beam is narrow - you have to be looking more or less right at the tower cab to catch it, so keep glancing at the tower as you maneuver.
4. Acknowledge when you understand a signal. In the daytime, rock your wings. At night, blink your landing light or navigation lights.

What’s the connection between Oshkosh and lost-comm procedures?

Every summer, the Experimental Aircraft Association runs AirVenture at Wittman Regional Airport in Oshkosh, Wisconsin, and for one week it becomes the busiest control tower in the world - more takeoffs and landings than Atlanta or Chicago.

The way they handle that flood is fascinating: they ask you to be quiet. On the famous Fisk arrival, you fly the railroad tracks to the right point. When a controller sees your airplane, they don’t ask for your call sign - they describe you: “High-wing Cessna over the gravel pit, rock your wings.” You waggle the airplane wingtip to wingtip, and that’s your acknowledgment. No mic, no words. The airplane becomes your radio.

That’s the same visual language FAR 91.125 built for a broken radio: see the airplane, give a visual instruction, get a visual acknowledgment. With that many aircraft, there simply isn’t enough airtime for everyone to talk, so Oshkosh leans on a hundred-year-old idea. Before radios were reliable, this is how towers talked to airplanes - with a lamp and a colored lens. It’s still in the book, still valid, and still tested.

Are light gun signals on the private pilot checkride?

Yes. The Airman Certification Standards (ACS) for the private pilot certificate list this under the area of operation for radio communications and ATC light signals. The examiner expects you to interpret the signals, not just recite the chart.

Expect a scenario: “You’re on downwind, your radio just failed, and the tower gives you a flashing green. What do you do?” The strong answer: “That’s return for landing, so I’ll continue in the pattern and watch for a steady green before I commit to land.”

What are the common mistakes with light gun signals?

They only apply at an airport with an operating control tower. Lose your radio going into a non-towered field and there’s no light gun coming - that’s a different procedure entirely, where you fly a normal pattern, watch for traffic, and blend in carefully.

Light guns are used rarely today. Many controllers don’t get to practice them, and many pilots have never seen one aimed at them. If it happens to you, give it a beat - confirm the color and whether it’s steady or flashing before you act. When in doubt, a steady red means circle and wait, and waiting has never hurt anybody.

The Oshkosh rock-your-wings system only works if you’ve done the reading. Controllers count on you knowing they’ll call your airplane by color and type, not call sign, and that your job is to wag your wings and follow the airplane ahead. Know the NOTAM, and practice rocking your wings gently on a calm day before you go.

Key Takeaways

• FAR 91.125 lets a tower direct a no-radio aircraft with a light gun using seven signals; light signals apply only at airports with an operating control tower.
• Learn them by logic, not rote: green = good, red = stop, white = go home; steady = now, flashing = not yet or a change; alternating red/green = extreme caution.
• If your radio fails, squawk 7600, get where the tower can see you, watch for the beam, and acknowledge by rocking your wings (day) or blinking your lights (night).
• Oshkosh AirVenture uses the same visual language on the Fisk arrival - controllers describe your aircraft and you rock your wings to acknowledge.
• Light signals are testable on the private pilot checkride under the ACS, and the examiner wants your action, not just the definition.