There is a possible bug I found, I believe for this mod specifically. Or it could be related with an official update, possibly other mods, but this is a problem I've seen of late prior to some of the other official updates the game was made upon.

On a rare occasion, which generally occurs when something like a ship is in motion, when you turn on your jetpack, suddenly it launches you through and out (literally) of your ship at breakneck speed; as well, you lose all control of your jetpack, with absolutely no way of slowing your speed down, nor will reversing your course do you any favours.

The current - and seemingly only - hotfix to this issue is to quit and restart your world again.