What was found
(CAN) WHEN FLAPS 450 SELECTED A/C ROLLS LT HALFWAY OF RT, AILERON TRIM NEEDED TO LEVEL WINGS, LT FLAPINDICATION JUMPS 400 TO 450 REPLACED RT NR 1 ACTUATOR , FLEXSHAFT ON INBD FLAP AND LT POS TRANSMITTER, PERFORMED RIGGING OF AILERON SYS AND FLAP SYSTEM, OPS NORMAL. THE FLAP POSITION INDICATION PROBLEM IN COMBINATION WITH A MISSRIGGED FLAP PANEL & AILERON PANEL WAS INTERPRETED BY THE PILOT AS AFLAP ASYMMETRY. AFTER LANDING, MAINTENANCE CHECKED THE FLAP SYSTEMAND FOUND RT FLAP ACTUATOR NR 1 LEAKING. DURING REPLACEMENT OF THE ACTUATOR, THEY NOTICED THE DEFECT FLEX SHAFT. TO SOLVE THE PROBLEM, FLAP AND AILERON PANEL WERE ADJUSTED AND THE POSITION TRANSMITTER WAS REPLACED.