What was found
FIVE HOURS BEFORE ARRIVAL FROM LAX INTO ZAZ, ATLAS AIR MCC NOTIFIED TO SERVITEC ZAZ TEAM (SERVITEC'S APPROVAL Nº 5VCY446D)LOST OF QTY IN HYD #4. ON ARRIVAL, ENGINEERS PERFORMED T/S AND REPLACED O'RING IN UPPER PLUG OF ALTERNATE BRAKE SWITCH MANIFOLD. DURING O'RING REPLACEMENT, A HYDRAULIC LEAKAGE OCURRED.