What was found
ON APPROACH THE PILOT NOTICED A HIGH PITCH WHINE COMING FROM WHERE HE BELIEVED TO BE THE RT ENG. AFTER THREE SECONDS THE PILOT NOTICED BOTH HYD LOW PRESS ANNUNCIATORS ILLUMINATED. CHECKED HYD QTY GAUGE & READING WAS 0. PILOT STARTED EMER PROCEDURES OUTLINED IN QRH, DECLARED AN EMER. MANUALLY EXTENDED LG & LANDED WITHOUT FURTHER INCIDENT. TROUBLESHOOTING REVEALED A CRACK IN THE HYD LINE LOCATED IN THE LT ENG AREA. R & R HYD LINE WITH SERVICEABLE UNIT, ALSO REPLACED BOTH LT & RT HYD PUMPS & INSPECTED THE SYS FILTER AS A PRECAUTION ALL WORK COMPLETED IAW ACFT MM 29-10-20. PERFORMED SYS OPERATIONAL CHECKS, LEAK CHECK & LG SWINGS IAW MM 29-00-00 & 32-00-00. ALL SYS CHECKS WERE NORMAL.