The wooden elytra loses durability depending on the height in which you are! It will also have different visual (and not-so-visual) effects depending on what's going on.
Every time your elytra loses durability, it will lose some feathers too. You can use this to identify how much durability your are losing, as well as how much durability you have left (Less durability means more feathers will appear) There is also some configuration options for managing dimensions in which it never burns Base Values (Can be edited on config):
Spoiler
"high-intensity" (Default: Y230+) = You will burn (if "burn" is set to true") and lose 1 durability every 3 ticks. "burn" (Default: true) = You will burn at high intensity "medium-intensity" (Default: Y150+) = Lose 1 durability every 5 ticks. "low-intensity" (Default: Y80+) = Lose 1 durability every 7 ticks. "durability" (Default: 80) = The amount of durability your wooden elytras have.Base Recipe (Can be changed by crafttweaker or similar mods):
