CREW WAS TAKING FLAT CAR TO THE END OF TRACK TO TIE IT OFF AND UNHOOK FROM THE MANTRIP. THE HIGHLINE SLED WAS LOADED ON THE FLAT CAR, AS THE FLAT CAR WAS MOVING, THE HIGHLINE SLED HIT A RIB BOARD ON THE LEFT SIDE OF THE ENTRY. THE SLED SLID SIDEWAYS AND PINNED EMPLOYEE BETWEEN BELTLINE AND SLED.