As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB OUT AT APPROXIMATELY 400 FEET, 60 KNOTS, AND 80 TORQUE HEARD A LOUD BANG THAT CAME FROM THE REAR OF THE HELICOPTER. THIS WAS FOLLOWED BY A SLIGHT LEFT YAW AND A RAPID LOSS OF ROTOR RPM. AN AUTOROTATION WAS ACCOMPLISHED. DURING THE DECENT THE TOT OVERTEMP LIGHT WAS OBSERVED TO BE ILLUMINATED. REPLACED ENGINE ASSEMBLY.