Originally Posted by
John Hill
With the exception of VDL Mode 4 (which I dont think is in common use?) what systems are there that provide a means for the pilot of one aircraft to be aware of the position of others aircraft near his?
A slightly more explicit response than PeeKay4
TCAS will give information on aircraft that are potential threats to the safety of your aircraft. The picture is somewhat distorted but the algorithms for alerting are excellent.
ADS-B (In) is the ability for an aircraft to receive and display the ADS-B transmissions of other aircraft. This is displayed in the cockpit on a display rather obviously called a Cockpit Display of Traffic Information (CDTI). This is a GPS map type display with the other aircraft shown on it with the ADS-B information that is available. CDTI is common in many small GA aircraft but airline operators are less keen to spend the money. (If you want to read about the development of CDTI do an internet search on
CAPSTONE CDTI ADS Capstone was an FAA project in Alaska looking into the use of CDTI. The search though will get you more information on other research and even EUROCONTROL aspects. I have flown with CDTI and the only drawback seemed to be (for GA) that there is a tendency to look down at the CDTI rather than out and as equipage in the open airspace with GA is not ubiquitous there could be aircraft out there that are not on your display while you are head down.
ADS-B (IN) that would allow CDTI in commercial aircraft cockpits is likely to be mandated in around 5 years or so for 5 years later than that. It may be supported by 'Aircraft Access to SWIM' (System Wide Information Management) that (amongst a lot of other things) could also provide the flight data of the other aircraft including its future trajectory rather than a prediction based on its last few seconds flight.