As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CRANK MAGNETIC PARTICLE INSPECTION SHOWS FATIGUE CRACK IN RADIUS OF FLANGE/JOURNAL TRANSITION. CRACK ALSO INDICATED JUST FORWARD OF OIL SLINGER. AIRCRAFT HAS NO DAMAGE HISTORY. CRACKS ARE ORIENTED TO PROPELLER BLADE POSITION. PROPELLER (HARTZELL HCCWYK4) APPLIES HIGH GYRO FORCES TO FLANGE. AIRCRAFT IS AN AEROBATIC TYPE.