As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ADC FAILED IN FLIGHT. PERFORMED QRH RESET CB'S F15 & F-14 ADC RETURNED AND FAILED A SECOND TIME. AIR RETURN TO DTW. MAINTENANCE REMOVED & REPLACED ADC P/N ON 622-4401-001, S/N ON 8129, P/N OFF 822-0370-123, S/N OFF 3304. OP CHECKS GOOD IAW THE SF340 MM CH 34-12-00-5.