What was found
WINDOW HEAT R FWD ADVISORY LOSS OF RIGHT FORWARD WINDOW HEAT (PRIMARY). NR 1 WINDOW CRACKED IN FLT DURING CRUISE, UNKNOWN CAUSE AT THIS STAGE BUT SEVERE WINDOW HEAT ARCING OCCURED AS A RESULT. DUE TO THIS EVENT R WINDOW HEAT PROTECTION HEAT UNIT REPLACED REF AMM 30-41-03. ALL OPS NORMAL AND P300 WINDOW HEAT TEST PASSSED. R WINDOW OUTER PANE SHATTER, WINDOW REMOVED IAW AMM DMC-B787-A-56-11-01-00A-520A-A. WINDOW RETAINER, WINDOW EDGE PROTECTOR AND NUTPLATE AND NUTPLATE STRIP INSPECTED FOR CRACKS, CORROSION OR OTHER DAMAGE. INSPECTION OK. R WINDOW REPLACED IAW AMM REF DMC-B787-A-56-11-01-00A-720A-A. CABIN PRESS CHECK CARRIED OUT IAW AMM, DMC-B787-A-05-51-24-00A-280A-A. CHECK WITHIN LIMITS.