I was able fly without issues now it this weird slow flight almost like a gliding flight. I can only fly in loops, difficult get off ground, or make any hard turn. I also can't slow down and it impossible to land? I this a toggle that I can turn off.

duplicate of #42

Check your mod pack, and remove the mod 'do a barrel roll,' this mod changes the normal elytra flight to a more 'realistic' feel, removing it fixes the gliding issue.