As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE ACFT WAS IN FLIGHT WITH A PATIENT ABOARD, PILOT NOTICED A GRADUAL LOSS OF VOLTAGE & AMPERAGE. AFTER SHEDDING SECONDARY ELEC EQUIP, VOLTAGE & AMPERAGE CONTINUED TO DECREASE WHILE A GEN LIGHT ILLUMINATED DURING FINAL DESCENT ON TO A MALL PARKING LOT. REMOVED STARTER GEN FOR INSPECTION & FOUND THAT THE BRUSH BRAID ATTACH POINTS WERE IN PIECES. THE BRAID ATTACH RIVETS ON THE BRUSHES BECAME LOOSE, THEN SEPARATED.