ILS intercept
What is the correct way to join/intercept an ILS ?
Some pilots I fly with use the normal 3:1 descent profile to descend to their destination and then capture the ILS (LLZ and G/S) whilst still descending. (without ever levelling off)
Is this ok ? Or do we have to intercept /capture the LLZ before the G/S ? Must we have to capture the G/S from level flight from below the G/S ? Or is Ok to capture it on a continuous 3 degree descent beginning from flight levels ?
I am particularly interested in how the airlines do it or other aircraft which have steep descent profiles.
Thanks.