What was found
(CAN) A HYDRAULIC LINE FROM THE NR 2 HYD SYS THAT FEEDS THE RUDDER PRESSURE REGULATOR DEVELOPED A HAIRLINE CRACK IN THE TAIL SECTION. . THE NR 2 SYSTEM HYDRAULIC QUANTITY DEPLETED TO BELOW MINIMUM. AN EMERGENCY LANDING GEAR EXTENSION WAS CARRIED OUT AND THE AIRCRAFT LANDED WITHOUT FURTHER INCIDENT. A FLEXIBLE HYDRAULIC LINE WAS INSTALLED TEMPORARILY AS DETAILED IN MAINTENANCE MANUAL CHAPTER 20-50-52. NR 2 HYDRAULIC PUMP WAS REPLACED AS A PRECAUTION, GEAR SWINGS CARRIED OUT AND THE AIRCRAFT RETURNED TO SERVICE.