Originally Posted by
411A
A minimum in-flight weight I can understand (many models of the B707 had this restriction) but exactly how could a minimum ZFW affect Vmc?
Because, at the limit, minimum in-flight weight cannot be less than minimum zero fuel weight.
So, if I certify using minZFW as my VMC min weight, I have conservatively covered the minimum flight weight case.
And minZFW is easier to control than minimum in-flight weight - if I weigh the empty aircraft I can usually quite easily show that I'm above the minZFW, without even worrying about crew etc. Since it's impossible to remove weight by loading the aircraft, that aircraft just automatically met any in-flight minima required.