Thread by @vcdgf555

For those of you who have wondered what ICAO spoofing is, or why it is getting so much attention lately, here is a short description of what is going on.

I will use @GDarkconrad's post as an example.

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https://twitter.com/GDarkconrad/status/1309035043008978945?s=20

1st, the callsign: a plane tracker will know from experience which are frequently used. Many air traffic radio enthusiasts over time have compiled 100s of callsigns assigned to particular aircraft. In this instance, MOJO is often seen in the Persian Gulf by refuel tankers.

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Callsigns can be a clue that a transmitter is receiving a false interrogation of its Mode-S receiver. Mode-S is a 6 digit code, using A-F letters and 0-9 numbers. Countries are assigned 3 digit prefix codes for their planes. In this case, AE0 is a code used for US mil planes.

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In certain circumstances, the plane along it's route will change from its preassigned callsign, but generally not its Mode-S code which is tied to a specific registration or tail number telling what it really is.

In this instance, N873GQ hasn't been assigned yet. It's bogus.

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