Fixed that folding plane that (link and comments made) , flies pretty well, your main problem was the weird shape at the back of the plane and the one engine in the middle. I fixed those problems, put on some wing landing wheels for the rear set of wings and gave it an icecoldlava paintjob. This plane goes up to 607mph, take off speed 295 ish mph. VTOL up for wings (do not do VTOL down) and group one to activate the landing brakes ( the two on each side are not enough after landing, but all of the air brakes are too much while in flight.) Some things to work on are aesthetics, more fuel and the back of the plane, I hope you enjoy this, all credit to (link and comments) for making this, have fun!