As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PVD - FLT491 - DURING TAKEOFF FROM PVD, THE ATTITUDE FLAG CAME INTO VIEW. BOTH THE FMC AND PMC WERE INOPERATIVE AND ON MEL AT THE TIME. FLIGHT RETURNED TO FIELD AT PVD AND LANDED WITHOUT FURTHER INCIDENT. NO EMERGENCY WAS DECLARED. MAINTENANCE REALIGNED BOTH IRU'S. SYSTEMS CHECK OK.