UNIT 1 WAS ANCHORED AND FISHING IN THE COOPER RIVER NEAR MULBERRY PLANTATION. WHEN HE WAS STRUCK IN THE SIDE BY UNIT 2. OPERATOR OF UNIT 1 WAS THROWN UNDER UNIT 1. UNIT 2 WAS AT CRUISNG SPEED. AFTER IMPACT UNIT 2 LOCATED OPERATOR OF UNIT 1 AND NOTIFIED DNR AND EMS. OPERATOR 1 WAS TAKEN TO ROPER BERKELEY THEN TAKEN BY HELICOPTER TO MUSC. UNIT 2 STATED THEY DID NOT SEE THEM AND THAT THERE WAS BAD GLARE ON THE WATER.