What was found
DURING TRANSIT OVERNIGHT SERVICE, IT WAS DETECTED THAT OCCASIONALLY THE FLAPS DID NOT RETRACT COMPLETELY AND, IF THEY WERE DOWN AND UP DID NOT STORE TOTALLY. AIRCRAFT WAS SENT TO THE HANGAR AND THE TWO SPEED VALVES AND PTU WERE REPLACED, IAW MM 27-52-01. ACTUATORS AND FLAPS CONTROL VALVE WERE REPLACED CONTINUING FAILURE. FLAPS ADJUSTMENT AND TESTED WERE PERFORMED IAW MM 27-50-00, ALL CORRECT.