I was testing the new snapshot for 1.11.1, and I dived to land and then ran into this bug. I recorded it right after it started.
The player was like it was flying, but it was actually walking around. I tried taking the Elytra off, but it did help.
Video: https://youtu.be/_N57l6_f1ms . It is unlisted. I posted it on YouTube since it is 26 megabytes.
Note: the bug was fixed when I restarted the game.
Environment
Ubuntu 16.10, java version "1.8.0_111", Java(TM) SE Runtime Environment (build 1.8.0_111-b14), Java HotSpot(TM) 64-Bit Server VM (build 25.111-b14, mixed mode). Dell Inspiron 14 series 64-bit, Intel® Celeron(R) CPU N3050 @ 1.60GHz × 2, Intel® HD Graphics 400 (Braswell), 2gb RAM.
The bug eventually came back after a little while. It is like I am flying, whenever I get hurt I jump like 5 blocks and the glide, same thing happened when I jumped.