Some Airbus verses Boeing Terminology FMC/FMGS & CDU/MDCU

[DaveCT2003 2553]

In flight simulation we often (too often) see people refer to a CDU or MCDU as an FMC, which remains completely inaccurate regardless of how many times people do this. We even have a few hardware developers in the flight sim world who do the same thing.

 

Of course there is no FMC in our Airbuses, and even if we did have one an FMC is actually black box found on Boeing aircraft and it only has cables coming in/out of it and is usually found in the avionics bay.

 

The Airbus has a FMGS which serves similar functions as the Boeing FMC, and of course the FMGS is also a black box located off the flight deck. 

 

On Boeings the CDU (Command Display Unit) is an input/output console from which the pilots can input and read back FMC data on.  On the Airbus it's referred to as an MCDU. 

 

With the above in mind, you will sometimes see people post that they "programmed the FMC/FMGS", and this is technically correct because they are programming the FMC/FMGS but doing so via that input/output console that we call a CDU on Boeing and an MCDU on Airbuses.

 

Anyway, given that some flight sim hardware developers even managed to get this wrong, I thought I'd take a stab at helping people to understand this better.

 

Best wishes!