Watch out below! The Chernobyl syndrome (let’s see what happens if we take the safety catch off and push this button) seems to be alive and well and living in Florida, although this time, there were no consequences: United Airlines reports that it has initiated use of the world’s first production quality TCAS computer-based airborne collision avoidance system – but it says thad in the flight tests, a DC-8-71 and a Boeing 737-300 were intentionally flown toward each other in a number of planned encounters to prove the system.