I think you're going to need something bigger than a .40 LA. I know you started out with the plans for a .25, but you've made the wing bigger, added a fuse, and I'm hoping you enlarge the tail feathers as well. It will take at the minimum a .46. If you make the wing bigger, the fuse needs to be longer and tail feathers need to be bigger. All that adds up to extra weight. I have an excel spreadsheet called design.xls that I use when I'm enlarging plans. You can look it up on the net or e-mail me and I can e-mail it to you.
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