As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ALTERNATOR COOLING FAN CAME APART IN FLIGHT AFTER TAKEOFF. PART OF COOLING FAN PUNCHED A HOLE IN INDUCTION AIR BOX DOWN STREAM OF AIR FILTER AND THE ALTERNATOR BELT CAME LOOSE IN THE ENGINE COMPARTMENT. LOSS OF ENGINE POWER FROM ENGINE FOD DAMAGE RESULTED IN AN UNEVENTFUL LANDING BACK TO THE AIRPORT. OUR FINDINGS CONCLUDE THAT THE COOLING FAN HAD A FRACTURED CRACK AT 1 OF THE COOLING FINS SPOT WELDS.