Originally Posted by
Adlerdriver
Yes, they have to see to land. That's why they have a 50' DH. DH means see to land.
Alert height is just a checkpoint for fail operational systems. Failure prior requires a go-around. Failure after will still allow the aircraft to safely land in the touchdown zone. There is no requirement to establish external visual reference at alert height.
I understand. What I meant to ask is are they flying CAT3b as a "see to land"? As you know, we (FX) are not required to have any visual cues to land under CAT3b.