Upon attempting to open a chest from a sunken ship, I was met with a long delay which eventually forced me to surface or drown in the water. The chest refused to open and I was forced to re-login. I tried again and afterwards decided to break the chest. After doing this, our server crashed resulting in a corrupted save. 

[INFO] com.mojang.authlib.GameProfile@18191e32[id=3d4a2c62-4448-4dda-9f64-d76b8e92bd42,name=Revenant69,properties={textures=[com.mojang.authlib.properties.Property@77eb3588]},legacy=false] (/216.189.134.47:61547) lost connection: Disconnected