Occasionally trying to grapple in 1.10.2 with no other mods causes minecraft to stall and then crash ~30 seconds later without giving an error log or any indication in the launcher that the game has closed. To continue playing I have to force close the launcher because it thinks that I am still playing.

This seems to be an ongoing thing, especially in the 1.12 version I'm working from. Mostly I have it happen when aiming straight up onto something. I'm not sure if the mod is getting stuck in calculating something or what. But if you let the freeze run its course, the client remains frozen while the server outputs can't keep up notifications.

Last messages from the mod itself are:
[16:28:58] [main/INFO]: [STDOUT]: BlockPos{x=80, y=26, z=525}
[16:29:07] [main/INFO]: [STDOUT]: null
[16:29:07] [main/INFO]: [STDOUT]: AIR FRICTION CONTROLLER
[16:29:20] [main/INFO]: [STDOUT]: BlockPos{x=70, y=18, z=534}
[16:29:21] [main/INFO]: [STDOUT]: null
[16:29:21] [main/INFO]: [STDOUT]: AIR FRICTION CONTROLLER
[16:30:23] [main/INFO]: [STDOUT]: BlockPos{x=79, y=12, z=546}
[16:42:09] [Server thread/WARN]: Can't keep up! Did the system

This kinda makes using grapple unplayable, because I can never tell when it's going to crash my world. Luckily, sending a kill signal, the server is able to save the world, and there is no corruption.