RedactedNarrative: V01 while docking collided with V02 that was already docked.  Upon arrival, I met with subject who at the time of the accident was assisting Operator1 dock his vessel to get fuel. Subject stated he was assisting V02 when V01 approached the dock. 
  
  He then went to hand a line to Operator1, who then realized the vessel was still traveling in reverse. When Operator1 went to correct this and put the vessel in neutral, he slipped and pushed the throttle to far forward. This action caused the vessel to move forward and collide with V02.
  