Right, the Auto-GCAS feature doesn't rely on radar -- but the normal TFR system does, so the OP was half-correct in that there is a system that can use the rada

Right, the Auto-GCAS feature doesn't rely on radar -- but the normal TFR system does, so the OP was half-correct in that there is a system that can use the radar to do ground collision avoidance... just not this particular system.