What does code 7600 mean?

Answer 1

Code 7600 refers to squawk code 7600, an emergency transmition code for airplanes.

There are three emergency squawk codes for an airplane's transponder:

7500 - Hijacking

7600 - Communications failure

7700 - General Emergency (running out of fuel, engine failure, etc)

Almost every airplane is equipped with a transponder to "squawk" information like altitude, relative position and direction of movement back to air traffic control (ATC.) The pilot can also program various four digit codes into the transponder to tell ATC additional information. For instance: if you squawked code 7600 (read seven-six-zero-zero) a signal on ATC's radar tells them you're without radio; if you squawked 7500 near a tall building you have a good chance of being shot down by an F-16. Another example is when flying under Visual Flight Regulations (VFR) conditions you would squawk 1200.