As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LHR INFLIGHT T292/10SEP ORD TO DEL - CAPTAINS FORWARD WINDSHIELD CRACKED IN FLIGHT AT 37000 FEET WITH ARCING ACROSS HEATER ELEMENT. DIVERTED TO LHR FOR REPLACEMENT AND LANDED WITHOUT INCIDENT. REPLACED WINDSHIELD. SYSTEM GROUND CHECKED NORMAL OPERATION.