What was found
THESE 2 EA PN RG-380E/44 MAIN SHIP BATTERIES WERE INSTALLED ON 10/30/2006. THESE BATTERIES WERE REPLACEMENTS FOR 2 EA BATTERIES THAT HAD BEEN IN SATISFACTORY SERVICE IN THIS AC FOR APPROX 48 MONTHS BUT FAILED A CAPACITY CHECK DURING A REGULAR SCHEDULED INSPECTION. LESS THAN 2 MONTHS AFTER INSTALLATION THE PILOTS WERE UNABLE TO START THE MAIN ENGINES USING THESE BATTERIES. AT THIS TIME THE BATTERIES HAD A TOTAL FLIGHT TIME OF 16 HOURS AND HAD PERFORMED 26 MAIN ENGINE STARTS AND 8 APU STARTS. THE MAIN ENGINES WERE STARTED USING A GROUND POWER UNIT. ALL CHARGING AND ELECTRICAL OPERATIONS APPEARED NORMAL. THE BATTERIES WERE REMOVED AND GIVEN TO REPAIR STATION FOR TESTING. BOTH BATTERIES WERE TESTED IAW (INST