As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAKEOFF, THE GEAR WOULD NOT RETRACT WHEN THE GEAR HANDLE WAS RAISED TO THE (UP) POSITION. THE GEAR THEN MOMENTARILY RETRACTED, THEN EXTENDED EVEN THOUGH THE GEAR HANDLE WAS STILL IN THE (UP) POSITION. MX REPLACED THE LT IB GEAR DOOR ACTUATOR. OPS CHECK AND GEAR SWINGS PERFORMED WITH NO DEFECTS NOTED.