I'm studying to become a pilot and stumbled upon the Raptor Aircraft a while ago.
In one of our subjects we briefly discussed the concept of the area rule but did not get into much detail since our teacher told us that for subsonic airplanes it is not very relevant, especially not for slow flying piston aircraft.
But the designer of the Raptor Aircraft gets into a lot of detail why the Raptor is shaped like it is and what performance benefits it provides.
To me the charts provided on this site make a lot of sense and it seems plausible that there is a drag reduction of 15%.
I get that for airliners 'ease of build' is a major factor and therefore the cabin is a cylinder (reasons described in this question). (Sidenote: as far as I know the A380 has a double bubble design.)
Here comes the question: can someone provide a chart of the cross sectional area like this one for the A320 or another jet airliner?
What interests me is how much performance gain/fuel savings/drag reduction could be achieved if one were to optimise the cross sectional area of an airliner.