What was found
DURING CLIMB-OUT, APPROX 8500' REPORTED NR 1 ENG COMPRESSOR STALL WITH A LOUD BANG, FIREBALL, & EPR DROP TO NEARLY "0" THEN RECOVERY. REPORTED ECAM ANNUNCIATED "COMPRESSOR STALL" THEN CLEARED AS ENG RESUMED NORMAL OPS. RETURNED TO ATL. MX T/S IAW AIRBUS 320 TSM. COMPLIED WITH VSV ACT LINKAGE LUBE IAW AIRBUS 320 MM. PERFORMED BOROSCOPE OF NR 1 ENG IAW AMM, NO DEFECTS NOTED. REPLACED 7TH STAGE BLEED VLE IAW MM. PWR ASSURANCE TESTS WERE GOOD ON NR 1 ENG IAW AWA TASK CARD F5M71312. DURING POWER ASSURANCE RUNS, THE NR 2 ENG EXPERIENCED COMPRESSOR STALL. VSV ACT ON NR 2 ENG LUBED & BORESCOPED NR 2 ENG IAW AMM. NO DEFECTS NOTED. ANOTHER PWR ASSURANCE RUN ACCOMP AND ALL SYSTEMS OPS NORMAL ON BOTH ENG.