Squawk 7700 signals an emergency to air traffic control

Based on · First reported 1 Oct 2026

Pilots enter the four‑digit transponder code 7700 to alert air traffic controllers that a flight is experiencing an abnormal situation that requires attention, and they continue communicating with controllers while the code is active.
The code prompts priority handling and assistance but does not automatically indicate an imminent crash, as the specific emergency can range from engine vibrations and smoke indications to medical issues.

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