What was found
DURING APPROACH, DURING FLAP EXTENSION, FLAPS STOPPED AT ABOUT 13 DEG, USED ALTERNATE EXTENSION TO 15 DEG. DECLARED AN EMERGENCY AND LANDED UNEVENTFULLY. THE AIRCRAFT WAS GROUNDED. PERFORMED VISUAL INSPECTION OF FLAP SYSTEM IAW AMM 27-51-00-210-801. NO DEFECTS NOTED. RAN FLAPS UP AND DOWN 6 TIMES OPERATED SMOOTHLY. NO GRINDING OR ERRATICALLY MOVEMENT. SERVICED B HYDRAULIC SYSTEM, NO LEAKS NOTED. AIRCRAFT OK FOR SERVICE.