What was found
AFTER A CONTINUOUS INSPECTION PHASE 1-5 WAS C/W, THE AIRCRAFT WAS RELEASED FOR A MAINTENANCE CHECK FLIGHT. A POST-FLIGHT SQUAWK WAS WRITTEN 'ON TEST FLIGHT, AILERONS FEEL LIKE THEY HAVE A CATCH GOING FROM LEFT BANK TO RIGHT BANK'. ON POST INSPECTION FOUND A MS27039-807 SCREW WAS CHAFING BETWEEN AILERON AND THE WING. SUBMITTER SUGGESTS ADDING TO MAINTENANCE RELEASE SHEET TO CHECK AILERON AIR CAP SEALS FOR FOREIGN OBJECTS PRIOR TO RELEASE.