As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER DEPARTURE THE NR 1 DC GEN FAILED INTERMITTENTLY RESULTING IN THE LOSS OF THE PILOTS & COPILOTS ADI, HSI & THE PILOTS AIR DATA INSTRUMENTS ACCOMPANIED BY CRC & GPWS WARNINGS & REPETITIVE CHIME. AN EMERGENCY WAS DECLARED. AIR TURN BACK WAS EXECUTED, THE FLIGHT LANDED WITHOUT FURTHER INCIDENT. AFTER TROUBLE SHOOTING THE GCU WAS FOUND TO BE BAD. THE GCU WAS REPLACED IAW JIC 24-32-81 RAI 10000. THE SYS CHECKED GOOD & THE ACFT WAS RETURNED TO SERVICE.