In the never-ending effort to squeeze more passenger revenue from a given capital cost and fuel burn, Airbus is now making their A320neo and A321neo single-aisle airliners available with what they call the “Space-Flex” cabin interior option. This relocates the galley and toilets, which were previously at the front of the cabin, to the very rear. This, combined with relocation of some doors, allows six more passenger seats in economy without changing seat spacing, expanding standard seating to 189 and the certification limit to 194, which makes it a close competitor to the Boeing 737-8 / MAX 200, which is marketed for a two class configuration of 178 (12 business, 166 economy) with maximum certification for 200 passengers.
The toilets and galley are heavy, and placing them at the back of the plane shifts the centre of gravity aft near the point where the plane would be unstable. This is particularly a problem in European two class configurations, where business has the same seats as economy but the centre seat is never occupied, resulting in less mass near the nose of the plane.... [Read More]