What was found
(CAN) A/C EXPERIENCED A LOUD BANG AND SHUDDER DURING CLIMB IN CLEAN AIR AND CLEAN CONFIGURATION. AFTER RETURN TO BLOCKS, A/C INSPECTED FOR BIRD STRIKE AND INSPECTION OF AIR CONDITIONING PACKS AND BORESCOPE CHECK OF ENGINES CARRIED OUT. NO DEFECTS FOUND. AIRCRAFT TT: 20,608 HOURS.