BaldEagle, My batteries are Thunderpower extreme 6s 5000mah. They weigh 26oz. With a 26oz pack ahead of the wing tube you may find the need for weight in the tail, unless you have mounted the rudder servo in the tail. I did not!

JB my Angel s50 assembly manual states Weight RTF less battery 77.4oz Add my 26oz pack = 103.4oz Mine weighs 106oz I have no clue how yours and BaldEagle's have come out so light. A fellow club member of mine also Has an Angels50, he says his weighs 102.4oz

Dave.