While my generators seem to be doing their job, I cannot start the alternators and all power drains away after about one hour in flight. The RED warning lights are constantly on. Clicking on the alternator switch moves it up, but it immediately springs back.
DISREGARD THIS TRANSMISSION - OUT
Solved it
I, too, find a significant drop in performance after about 90 minutes in flight. 90 minutes of good performance with just the odd stutter, and then the frame rate drops dramatically, and within a few minutes, it is uncontrollable.