What was found
DIVERSION AND EMERGENCY LANDING AT COLUMBUS, OHIO, FOR LOSS OF PRESSURE IN YELLOW HYDRAULIC SYSTEM. IN-FLIGHT INDICATIONS FOR HYDRAULIC YELLOW ENGINE PUMP LOW PRESSURE, YELLOW SYSTEM LOW PRESSURE, AND YELLOW HYDRAULIC QUANTITY LOW. FOLLOWED QRH PROCEDURES FOR OVERWEIGHT LANDING; TOUCHDOWN APPROX 0-50 FPM. NO OVERWEIGHT INSPECTION REQUIRED PER FLIGHT OPS MAUAL 04-02-10 AND AMM 5-51-11. WALK AROUND FOUND NO DEFECTS. FOUND 'B' NUT ON BRAKE ACCUMULATOR LOOSE. TIGHTENED SAME AND SERVICED HYDRAULIC SYSTEM, LEAK CHECK AND OPS CHECK NORMAL.