In our modern world, there is the change to see aircraft flying on your device like smartphone, tablet or PC from one to the other destination. What is common in the civil aviation is way diffferent with military planes. First, mostly nowbody should know where the aircaft is flying. But sometimes our little C-2A aircraft has to fly international or must cross civil airspace. For this reason, the use a flight number as well as a squak.
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Here are some screen shots of the C-2A
The C-2A(R) BuNo 162148 of the VAW-120 left Norfolk and was flying along the cost line to New York. As they travelled in a very busy civil sector, it was possible to track them as they were like a standard airplane in the IACO world. Using call sign "GRYHK31" - their Modex number is 631 and squak 6511 that was given from the air traffic contoller. I was lucky to catch them flying.