Nyal Williams wrote:
I'm sure I've seen an article about anti-collision
radar available for corporate aircraft. I believe
that they are available, but am unsure how prevalent
they are. There was some comment about this in AOPA(?)
mag a couple of years ago.

It's called TCAS (Traffic Alert/Collision Avoidance System). It's not
radar based, it broadcasts an interrogation signal which causes any
nearby transponders to respond. It calculates range and bearing to
transponders that respond, and shows them on a display in the cockpit.
If there appears to be the threat of collision, it sounds an alarm. If
the other aircraft is TCAS equipped, the two units actually negotiate an
avoidance strategy, then advise the pilots how to maneuver away from the
other aircraft.

Marc