RedactedNarrative: Vessel #1 had just launched in the river, 3rd party pontoon was coming at him on other side of river, operator of vessel #2 beeped the horn at oncoming vessel to warn vessel #1, operator of vessel #1 moved throttle forward way too much throwing him to back floor of boat and causing vessel #1 to crash into vessel #2 and not stop until it was almost on top of it completely.  No injuries were reported.