TCAS II: two tread detection logics, which one is true?
I currently doing some research works on the TCAS, the references online is quite unclear about its working logic, lets assume:
DHL and FEX are flying in parallel, @same height, horizontal separation far enough. DHL flies 10 times faster than FEX and takes over it.
Logic1: TCAS tracks and then projects both planes route on a global coordinate, for sure it will found that the two routes are parallel and has no interception, alarm would not be triggered.
Logic2: TCAS only tracks the range and relevant closing speed of the two, that means the TCAS shows the planes is rapidly coming closure to it. TCAS will alarm.
Which logic is true to TCAS???