RedactedNarrative: UNIT 2 BEGAN TO SLOW DOWN. UNIT 1 WAS INATTENTIVE AND FAILED TO MAINTAIN A PROPER LOOK OUT. UNIT 1 COLLIDED WITH THE STERN AREA OF THE SKI AND DAMAGED THE SEAT ON UNIT 2. THE OPERATOR OF UNIT 2 AS A RESULT OF THE IMPACT, SUSTAINED INJURIES TO HIS RIBS AND LUNGS FROM THE STEERING AREA OF THE SKI.