for video of assembly of an airbus A340 click on
hope you got a high speed internet connection.
I have been on the airbus production line (not with the tour I add, so you get a more realistic look without the PR
spin). As mentioned, its a modular construction and the amazing thing is how quiet the construction building is (I am in a heavy maintenance back ground, so I am used to the sounds of rivet guns, fork lifts, air hoses, guys screming at each other etc) and the size of the A340 assembly hall is vast. Its basically a giant Airfix kit being bonded together, with the most fantastic and up to date machinary imaginable.
How long is production? well how do you classify that (landing gear and engines are constructed in batches etc) everything is on different lead times.
At airbus the fuselage sections are lined up ready to mate.
Last time I was at Airbus one machine was giving problems, on the fuel tests it kept leaking and all I heard was complaints about contract labour (got to blame someone I suppose)