What was found
(CAN) WHILE THE AIRCRAFT WAS IN CRUISE AT 15,000 FEET, NR 4 HYDRAULIC PUMP CAUTION LIGHT ILLUMINATED, FOLLOWED 5 MINUTES LATER BY NR 3 HYDRAULIC PUMP CAUTION LIGHT COMING ON. ALL HYDRAULIC PRESSURE WAS LOST ON NR 2 HYDRAULIC SYSTEM AND ALTERNATE LANDING GEAR EXTENSION WAS CARRIED OUT AND THE AIRCRAFT LANDED WITHOUT INCIDENT. HYDRAULIC PUMP P/N 63054-02/05 NR 4 HYDRAULIC PUMP P/N 225961- NR 4 PUMP PRESSURE DROP TO ZERO. NR3 HYDRAULIC PUMP P/N 167136- NR 3 PUMP SHAFT BROKEN PRESSURE DROP TO ZERO.