I have been told by almost all jet pilots that you balance your jet with a full UAT. I think and know that this is a dangerous practice. The weight of the fuel/oil mixture is almost 1 oz per oz of fuel. This means that you are balancing your jet with almost ½ a pound of fuel that may not always be there. Every time I have seen a turbine run out of fuel the UAT is sucked dry. This means that when you are in the worst position during a flight ( you run out of fuel) your jet (witch is now a glider and not a very good one) you may be tail heavy. Whether you are balancing a ½ control line airplane or a 747 you never balance it with usable fuel in it…..