What happens when a hacker gets bored and starts looking at an aircraft tracking systems? This talk will look at ADS-B (Automatic Dependent Surveillance-Broadcast), a common technology installed or being installed on a vast majority of commercial airliners that involves an unencrypted and unauthenticated radio broadcast. This technology has some interesting features and weaknesses that are a useful lesson in failures when security is not built in from the beginning. This talk constitutes a work in progress and hopes to spur more research and investigation into this field.