RedactedNarrative: UNIT 1 AND UNIT 2 WERE TRAVELING NORTHBOUND IN THE WANDO RIVER.  UNIT 2 WAS APPROXIMATELY 30-40 YARDS BEHIND UNIT 1.  UNIT 1 SLOWED DOWN AND UNIT 2 WAS UNABLE TO MANEAUVER AWAY AND AVOID A COLLISION.  UNIT 2 STRUCK UNIT 1 IN THE ENGINE AND PORT SIDE CAUSING FIBERGLASS DAMAGE.