What was found
(CAN) FLT CREW WERE UNABLE TO EXTEND LT MLG THROUGH NORMAL (HYDRAULIC) OR EMERG (HYDRAULIC/PNEUMATIC) MEANS PRIOR TO LDG. LOSS OF HYDRAULIC FLUID EVIDENT AROUND TRAILING EDGE OF LT WING & FLAP AREAS. NOSE & RT MLG WERE RETRACTED & A/C MADE SUCCESSFUL GEAR UP LDG. INVESTIGATION. DETERMINED LT MLG ACTUATING CYLINDER TOP BOLT HAD BROKEN. ALLOWED CYLINDER TO SLIDE DOWN RAM WHEN GEAR INITIALLY SELECTED DOWN, INSTEAD OF RAM RETRACTING INTO STATIONARY CYLINDER. CYLINDER MOVEMENT BROKE LOWER FITTING THAT IS COMMON TO BOTH HYDRAULIC&PNEUMATIC SYS PRESSURES, RESULTING IN OVERBOARD LOSS OF HYDRAULIC FLUID A ND ANY PENUMATIC PRESSURE: