As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF BOTH AHRS SHOWED GYRO AND COMPUTER FLAGS. NR 1 ADI CIRCUIT BREAKER OPENED. RETURNED FOR LANDING. AFTER LANDING, GYRO FLAGS DISAPPEARED BUT COMPUTER FLAG REMAINED ON CAPTAINS ADI. REPLACED NR 1 INVERTER. BOTH AHRS AND ADI'S CHECKED NORMAL WITH NO FLAGS IN VIEW.