As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PIT - FLT 1080 - FIRST OFFICERS NR 2 SLIDING WINDOW BEGAN ARCING IN FLIGHT AT FL310. WINDOW CRACKED SHORTLY AFTER WINDOW HEAT WAS TURNED ON. FLIGHT DIVERTED TO PIT AND LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE REMOVED AND REPLACED THE NR 2 SLIDING WINDOW PER MM 56-12-00 AND SWAPPED WINDOW HEAT CONTROLLER (P/N 83000-05602) AS PRECAUTIONARY MEASURE. OPERATIONAL CHECK GOOD. (M)