I am changing my DC-6s into DC-8s. I am also flying BA11s, but not changing them.
I just retired two DC-6s...and my commonality costs doubled, across all three of my fleets!
My fleet groups are the same (three types), and my total airframes are reduced by two...so how can my maintenance, admin, and training costs all DOUBLE, on every fleet, when my fleet is actually smaller than before? Why does it cost double to do MX on fewer planes, when it would cost only half the price to do the MX on those exact same planes plus two more?