Interesting new technology designed to replace ATC radar. Have a look at the videos here http://www.airservicesaustralia.com/pilotc.../sampleadsb.htmUses onboard equipment which collects a/c data ( position via GPS, altitude speed, etc) and transmits to ground station for ATC control. Much cheaper than current use of primary and secondary ATC radars.Barry

Unreliable, easy to spoof (just turn off the transmitter and you're invisible), extremely liable to fraud (set another code and you're someone else).Terrorists and drugs couriers will just love it.

>Unreliable, easy to spoof (just turn off the transmitter and>you're invisible), extremely liable to fraud (set another code>and you're someone else).... the same as current transponders, you mean? I think that this sort of system is meant to complement current systems. Obviously they aren't going to get rid of ATC radars, since there will always be a need to monitor the airspace for the reasons that you outline above.Also, turning off a transponder probably sends a better indication of the bad guys intent, so in that sense, it doesn't spoof anyone.- Martin