What was found
AFTER TAKEOFF, THE LANDING GEAR WOULD NOT RETRACT. HYDRAULICS WERE NORMAL, NO OTHER ABNORMAL INDICATIONS. RECYCLED GEAR, OPS CHECKED GOOD. NO FURTHER DIFFICULTIES. INSPECTED ALL THREE LANDING GEAR AND DOORS. NO DEFECTS NOTED. CYCLED LANDING GEAR FOUR TIMES IAW DC-9 MM 32-30-00-2-0001. OPS CHECKED GOOD EACH TIME.