While an aficionado of the 'bus, I have wondered about the cost efficiency of the trim tank on the 330/340. AFAIR the MEL penalty for trim tank inop is 1.5%, I could look it up but it is nearly lunch time. In my experience with this MEL, we get the 1.5% but seem not to use it. I wonder if the cost/benefit analysis is there, especially in the 1-8 hour regime which is where we operate - I suspect not.
I guess the tanker guys will take the full 109 tonnes (ish) and be grateful for the extra 5 tonnes in the tail, or at least the F35 guys will be, on some 5000 mile deployment.