IAN is a way of using FMS vertical glide path when ILS glide path is not available. Airbus has a similar system and calls it FLS or Flight management Landing System. It may be a VOR approach where vertical guidance is not coded in FMS, what's called managed in Airbus or using ILS localiser only approach because GS is not available. It cannot be that IAN will use ILS when you want to do a VOR approach. because which minima will you use. It helps flying a non precision approach ILS like with FD LOC and GS indications but from FMS. It cannot be used for RF leg approach.
Last edited by vilas; 26th Nov 2021 at 04:45.