EMER RETURN LAND ON ACR LGT WHEN ACFT EQUIP PROBLEM WITH LOSS OF HYD FLUID AND SYS PRESSURE RESULTS IN PARTIAL GEAR UP LNDG. ACFT EVACUATED.

Narrative

I DEPARTED TJSJ IN AN LGT BOUND FOR KPHL. AFTER TKOF WITH THE GEAR ON THE WAY UP; THE FLT ENGINEER CALLED; 'L GEAR DOOR LIGHT ON (CONTINUALLY).' THE FO CALLED; 'A SYS HYD PRESSURE LOW LIGHTS ON.' CHKING FURTHER; 'A' SYS HYD QUANTITY AND PRESSURE WERE ZERO. WITH SJU DEP CTL CONCURRENCE; I DECLARED AN EMER AND DUMPED FUEL. A SYS LOSS OF HYD FLUID CHKLIST WAS COMPLETED AND THE FLT ATTENDANTS (5) PREPARED THE PAXS (149) FOR RETURN TO TJSJ. WHILE EXECUTING THE MANUAL GEAR EXTENSION CHKLIST; THE R MAIN GEAR WOULD NOT COME DOWN. SJU DEP CTL VERIFIED THAT THE TWR COULD SEE MY R GEAR UP ON THE WHEEL WELL WITH THE GEAR DOOR OPEN. A LOW APCH TO 400 FT PAST THE TWR RECONFIRMED R GEAR WAS UP. I THEN STARTED A SECOND FUEL DUMP TO LAND WITH AS LITTLE FUEL ON BOARD AS POSSIBLE. THE FLT ATTENDANTS THEN PREPARED THE PAXS FOR LNDG AND EMER EVAC. COCKPIT BRIEFING AND CHKLISTS WERE COMPLETED. I PROCEEDED TO LAND AT TJSJ. THE L MAIN GEAR CONTACTED THE RWY FIRST; THEN THE NOSE; THEN THE R OUTBOARD FLAP AND WING. A SLOW SKID DEVELOPED TO THE R AND THE ACFT LEFT THE RWY AT 100 KTS DECELERATING TO A STOP. EVAC COMMENCED AT THAT TIME WITH NO INJURIES. MY FLT AND CABIN CREW; PERFORMED IN A VERY EFFICIENT AND PROFESSIONAL MANNER WHICH MADE A DIFFICULT SITUATION MUCH EASIER TO HANDLE.