As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CAPTAIN'S VERTICAL GYRO FAILED ON ROTATION. FLIGHT RETURNED TO MSP AND LANDED WITHOUT INCIDENT. REPLACED THE NR 1 VERTICAL GYRO WITH NO HELP. REPLACED NR 1 ATTITUDE DIRECTIONAL INDICATOR. OPERATIONAL CHECK OK. AIRCRAFT RETURNED TO SERVICE.