HYD SYS LOSS RESULTS IN RETURN TO LAX; CA; SEVERAL MINS AFTER TKOF.

Narrative

SEVERAL MINS AFTER TKOF THE L HYD QUANTITY EICAS MESSAGE FOLLOWED BY L HYD RESERVOIR AND L HYD PRESSURE APPEARED. DECLARED AN EMER. COMPLETED APPROPRIATE CHKLISTS. CONTACTED DISPATCH; SAM F'S. LANDED NORMALLY AT LAX; FLAPS 20 DEGS OVER LNDG WT AT 202;000 LBS BECAUSE I DEEMED IT AS SAFE TO LAND OVERWT AS TO BURN OFF FUEL. FO CALLED DUTY FLT MGR AT XA50 PST AND OK TO FLY NEXT LEGS. SUPPLEMENTAL INFO FROM ACN 491976: SEVERAL MINS AFTER TKOF FROM RWY 25R AT LAX; L HYD QUANTITY EICAS MESSAGE APPEARED FOLLOWED BY THE L HYD RESERVOIR AND L HYD SYS PRESSURE EICAS MESSAGES. DECLARED AN EMER WITH LAX WHILE COMPLETING APPROPRIATE CHKLISTS. CONTACTED DISPATCH; MAINT AND INFORMED FLT ATTENDANTS. RETURNED TO LAX TO LAND ON RWY 25R. AFTER DISCUSSION WITH MAINT; CREW DEEMED IT SAFE TO LAND OVERWT AT A GROSS WT OF 202000 LBS. AFTER UNEVENTFUL LNDG; CAME TO A COMPLETE STOP ON THE RWY. HAD RESCUE CRE WAS INSPECT EXTERIOR AND ACFT WAS THEN TOWED TO THE GATE BY MAINT. CALLBACK CONVERSATION WITH RPTR ON CAN 491977 REVEALED THE FOLLOWING INFO: CALLBACK REVEALED THAT THE FAILURE WAS A HYD LINE IN THE L MAIN GEAR RETRACTION SYS. THE LEAK WAS SLOW ENOUGH THAT FLAPS WERE RAISED NORMALLY BEFORE EICAS WARNING WAS RECEIVED. DURING PERFORMANCE OF IRREGULAR OP CHKLIST IT WAS DISCOVERED THAT THE PWR XFER UNIT DID NOT WORK SO THAT LNDG GEAR WAS LOWERED USING THE STANDBY SYS. CHKLISTS WERE ADEQUATE FOR THE OP.