What was found
IN FLIGHT THE LT LANDING GEAR WOULD NOT COME DOWN. THE PILOT WAS ABLE TO MANUALLY GET THE GEAR DOWN AND LOCKED FOR LANDING. UPON INVESTIGATION IT WAS DISCOVERED THAT THE LT MAIN LANDING GEAR PIVOT ASSEMBLY SHAFT WHERE THE ACTUATOR ATTACHES HAD BROKEN AND WHEN THE GEAR WAS SELECTED TO THE DOWN POSITION THE ACTUATOR COULD NOT MOVE THE LT GEAR. IT APPEARS THAT THE SHAFT TO CRACK HALF WAY AROUND THE CIRCUMFERENCE OF THE SHAFT OVERTIME WHICH CAUSED THE FINAL FAILURE OF THE SHAFT. AT SOME POINT AND TIME THERE SHOULD BE A REQUIREMENT FOR THE GEAR TO BE REMOVED FOR A DETAILED INSPECTION. THE AREA IN WHICH THE FAILURE OCCURRED ON THIS PIVOT ASSY COULD ONLY HAVE BEEN SEEN WITH LANDING GEAR REMOVED.