Originally Posted by
Chris Scott
In terms of volume, are you suggesting that on narrow-body airliners the centre-section void occupied by the centre tank could otherwise contain baggage/cargo?
No, I'm saying that a centre tank, typically between the wheel wells, is the only space that couldn't otherwise (easily) be used for baggage/cargo.
But when additional centre tankage is fitted (727, Airbuses, etc), the space that it occupies reduces baggage/cargo volume.