@whitequark and removing a row of business gets you a lot closer to the next-size-smaller plane (with lighter fuselage, lower fuel burn per mile, etc) than removing a row of economy, and it also potentially allows you to fly more people on the same fuselage by adding more economy, which reduces the per-passenger fuel burn…
@rcombs hm, is it actually the case that smaller planes have lower fuel burn per mile? that doesn't make sense to me. why even have big planes if so
@whitequark if it wasn't true, why even have small planes? any given plane is most efficient per-passenger-mile when flown close to 100% load-factor
a smaller version of the same plane (same engines, avionics, etc) has lower dry weight and will cost less to fly empty
on the other hand, flying 1 big plane is usually more efficient than flying 2 planes that are half the size, because the 1 big plane has less dry weight than the 2 small ones (and costs that are fixed regardless of size, related to eg drag and takeoff/landing, would be increased in the 2-small-planes case)