As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING OVERHAUL, MAGNETIC PARTICLE INSPECTION REVEALED MULTIPLE INDICATION IN THE LOWER SPLINE AREA OF MAIN ROTOR SHAFT. LONGEST INDICATION MEASURED APPROX .500 INCH IN LENGTH, BEGINNING IN THE ROOT AREA EXTENDING OVER SPLINE FACE, DOWN TO THE NEXT ADJACENT ROOT AREA, INCLUDING UP TO THREE CRACKS ON SAME SPLINE.