Airbus DME's
Hi,
I was looking at an A330 FCOM in the RADIO NAV section, and I saw something interesting. To paraphrase, it said that the aircraft had 2 DME's, and the frequency is paired with the VOR / ILS. It went on to say that up to 5 ground stations can be tuned by the FMC.
My question is if there are only 2 DME's installed, how can the FMC tune 5 ground stations?
I remember reading somewhere that the 744 also has 5 DME inputs available, so maybe it's not just an Airbus thing.