Boat does not stop at the end of a mission


I have a boat with the pixhawk 2.1 system, herelink remote controller. I use the Qground control system and I have noticed sometimes that after a mission the boat will not stop, it speeds up to a speed of 4 knots (cruise speed of 2 knots). Why does it sometimes not stop and others just speed up to max speed? How can I fix this (I have crashed the boat multiple times)?

If your plan has a command in to to stop the boat then you should ask the questions on a firmware forum. QGC is not running the mission it only uploads it to the vehicle. After that the firmware takes over.