As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AIR TURNBACK DUE IRS INOPERATIVE. ACFT HAD NR 2 IRS INOPERATIVE. RT IRS FAULT LIGHT ILLIMINATED IN FLIGHT. NR 2 ADIRU REPLACED AND TESTED SERVICABLE IAW MM 34-21-01. THIS DIVERSION WAS OPS IN NATURE DUE TO PARTS AND MANPOWER AVAILABILITY AT BASES IN QUESTION.