As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE PERFORMING 100 HOUR OR ANNUAL INSPECTIONS WE ARE FINDING THE AFT BULKHEAD ON THE MAIN FUEL TANKS CRACKED AT THE INBOARD SIDE BEND RADIUS WHERE IT ATTACHES TO THE WING. ALL CRACKS ON ALL THE BULKHEADS WERE IN THE SAME GENERAL AREA. WE HAVE FOUND THAT BOTH THE LEFT AND RIGHT BULKHEADS ON OUR 402B0546 WERE CRACKED, BOTH WERE REPLACED.