What was found
ON FLIGHT 3648 (CVG TO ORD) FLAPS FAIL ON APPROACH WHEN SELECTED TO 20. AIRCRAFT LANDED SAFELY AND PROCEEDED TO THE GATE. REMOVED AND REPLACED ALL FLAP ACTUATORS FOR THE INBD AND OTBD FLAPS, LEFT WING IAW CRJ AMM 27-53-01 REFER TO AML 2156655-1-2. INSPECTED CLEANED AND LUBED THE LEFT WING FLAP FLEX DRIVE SYSTEM IAW CRJ AMM 27-53-10 REFER TO AML 2156653-1. REMOVED AND REPLACED THE SKEW DETECTION UNIT IAW CRJ AMM 27-15 REFER TO 215 6656-1 TROUBLESHOOTING AND MAINT. PERFORMED PER MOTORGROUP DMI CLEARED AND PLACARD REMOVED.