Vintage

According to Wikipedia, ACARS (or Aircraft Communications Addressing and Reporting System) ) is a digital datalink system for transmission of short, relatively simple messages between aircraft and ground stations via radio or satellite.

So what does this mean?  Well first, the magic word (radio) has been mentioned. Also, the ACARS protocol is very well documented and publicly available.  This allows a radio enthusiast, such as myself, to observe these ACARS communications between aircraft and ground systems.  

 Using only my Radio Shack Pro-97 scanner and the AT124 telescopic antenna, I can connect the line-out on my scanner to the line-in on my computer to get these messages real-time just as a ground reporting station would.  I use a program called PlanePlotter to decode the digital data from the audio stream and display the ACARS information.  I do get a few flights, though I think I'd get more with an outdoors antenna better suited for the frequencies.  Regardless, it's cool to keep track of the flights that "check in" every night, which is what I'll use the ACARS category for.

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