Here's how you do an all flying wing the right way!
http://youtu.be/5oekW0LFiL0
123" wingspan, twin 90mm edf's, 33lbs. NO vertical stabilizers. "Drag rudders" used for marginal yaw control.
http://youtu.be/3UFLtHUbl_Y
yes i built it, yes i flew it, and yes its been done more than once!