As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RETURNED TO BOS WHEN INTERTIAL REFERENCE UNITS WOULD NOT ALIGN. OVERWEIGHT LANDING. *S/D* CREW ATTEMPTED A QUICK ALIGN WITH THE AIRCRAFT IN MOTION. IRS SYSTEMS WERE SUCCESSFULLY ALIGNED ONCE THE AIRED AND NORMAL ALIGNMENT PROCEDURES WERE FOLLOWED.