4 ms·
I agree with the first point but not the second. Transponders enable TCAS and TCAS has saved many lives.
by aftbit 2y ago
I agree with the first point but not the second. Transponders enable TCAS and TCAS has saved many lives.
- felsokning 2y agoThose were radar-based (before ADS-B), I thought?
- aftbit 2y agoNope, TCAS has always been based on secondary surveillance (i.e. transponders). Before ADS-B, it was based on Mode S. Air traffic control has used primary radar and even more primitive methods (position/speed/bearing reports over radio) to maintain separation since long before transponders. The in-cockpit automated "traffic traffic" advisory and "climb climb" or "descend descend" resolution advisory come from TCAS, which relies on transponders.