What was found
ON T/O FROM OXC, WITH 0 PAXS, PILOTS ALERTED TO A LOSS OF HYD PRESSURE. INDICATING & HYD SYS CHECKED, & CONFIRMED SYS LOSS OF PRESSURE HAD OCCURRED. A/C RETURNED TO OXC FOLLOWING AFM PROCEDURES. VISUAL INSPECT REVEALED LT ENG COWL WET WITH HYD FLUID. MX ESTABLISHED LT ENG HYD PUMP PRESSURE HOSE RUPTURED. A REVIEW OF A/C RECORDS INDICATED SUBJECT HOSE HAD NOT BEEN REPLACED SINCE 1978, AS WELL A PROTECTIVE FIRE SHEATH COVERING POINT THAT RUPTURED PRECLUDED THAT A VISUAL INSPECT WOULD HAVE FORETOLD AN IMPENDING FAILURE. AS A PRECAUTION, SUCTION HOSE & CASE DRAIN HOSE ASSY REPLACED. SYS FLUSHED & SERVICED, BOTH HYD PUMPS WERE REPLACED. A/C JACKED & AN OPS CHK OF HYD SYS CONDUCTED WITH NO ABNORMALITIES.