Squawk 7700, 7600 and 7500: What Emergency Codes on Flight Trackers Mean
Sometimes a plane on the map turns red and shows squawk 7700. Social media notices fast, and people start to worry. Here is what those codes really mean.
What is a squawk code?
Every airliner has a transponder, a radio that answers air traffic control radar. Controllers give each flight a four-digit code, called a squawk, so they can tell planes apart on their screens. The digits go from 0 to 7, so codes run from 0000 to 7777.
A few codes are reserved for special situations. Pilots can set them themselves, and every controller recognises them at once.
The three emergency codes
| Code | Meaning | What it usually is |
|---|---|---|
| 7700 | General emergency | A medical emergency on board, a technical problem, a bird strike, smoke or fuel concern |
| 7600 | Radio failure | The crew can't talk to air traffic control |
| 7500 | Unlawful interference | A hijacking or threat on board |
A popular way to remember them: seven-five, man with a knife; seven-six, radio needs a fix; seven-seven, going to heaven. The last one is a joke. A 7700 almost never means that.
7700: the one you will see most
Pilots are trained to declare an emergency early. Setting 7700 gets them priority: a direct route, the runway of their choice and fire services waiting, just in case. Common reasons include:
- A passenger who is seriously ill and needs a hospital quickly.
- A warning light or a technical fault that the crew wants checked on the ground.
- A bird strike or a cracked windscreen.
- Returning to the departure airport soon after take-off.
The vast majority of 7700 flights land normally, and passengers often only notice a fire engine next to the plane.
7600: no one can hear them
When the radio fails, the crew follows set rules: keep the last cleared route and altitude, then descend and land according to the published procedure. Controllers clear the way around them. Radio problems are usually fixed or worked around quickly.
7500: very rare
Pilots set 7500 only if there is unlawful interference with the flight. It is extremely rare. A wrong code can be entered by mistake, and controllers check it calmly with the crew.
How fly24 shows emergencies
When a plane on fly24 sends 7700, 7600 or 7500, its details show the squawk code, so you can follow the flight until it lands. If you see one, remember: an emergency code means the crew is getting help, and help is very good at its job.