I don't know a lot about xml modding but yeah make it weigh less

@FireDrake your welcome even though when it comes to the real world with gliding planes if you ever wanted to make a real custom plane and glide it center of mass has to be in front of Center of lift make sure it's not to far ahead of to close well that depends on size also btw center of mass is the middle of weight of the object and say if you put your finger there you you can balance it that's why sometimes it's called center of balance and also if you ever do make a glider here's a tip wings split the air when they move through it causing under and over drag with a bigger and larger vertical tail wing you can fly straight as in with unwanted turning to left to right

@Zanbradcr3per @Ultra0 Thank you. I’m still kind of an idiot when it comes to that stuff. You guys are helping me immensely with your guidance

Center of mass is behind center of lift plus you put dead weight in the back remove that dead weight in the back and Center of mass will be ahead of Center of lift if you have a plane listen to me for it to glide/fly center of mass MUST be in front of Center of lift

Plus I had some problems taking off not enough quick acceleration

It seems the main problem with this is that most of the fuselages take the maximum fuel making it too heavy so reduce the amount of fuel across the aircraft and make sure the mass indicator is inline with lift