The elytra deactivates when you use a bow
steps to reproduce
1.Run and jump off a hill or cliff(Important)
2.activate elytra
3.shoot a bow
You will see that the elytra deactivates, only way to work around this is to -
1.create a pillar of blocks
2.walk off the edge (don't jump)
3.activate elytra quickly
When you do that the elytra doesn't deactivate when you shoot a bow.
Just noticed this in 1.1.0.55, seems to happen when the drop is ~<15 blocks.
https://youtu.be/cS4sHNFXRv8