B787 flight crew reported window heat arcing and delamination in flight. Flight crew performed fuel dump; returned to departure airport; and landed safely.
Synopsis
B787 flight crew reported window heat arcing and delamination in flight. Flight crew performed fuel dump; returned to departure airport; and landed safely.
Narrative
Window Heat Arcing and Delamination. On climbout the FO noticed and pointed out that the heating element in his forward window would occasionally glow bright orange and then dim. The Captain stated that they would call Maintenance about it at cruise altitude as we were climbing though a bit of weather and wanted to get clear first. I left for my break shortly after. About 30 minutes or so later I received a call in the bunk from the Captain stating that we were going to be returning to ZZZ. I returned up to the flight deck and the Captain briefed me on what had happened. He had called Dispatch and Maintenance and a joint decision was made to return to ZZZ. We had already turned around and were heading to ZZZ. They had elected to dump fuel vs landing overweight due to weather and wet runways in ZZZ. Next the Captain and I ran through the fuel jettison un-annunciated checklist and all three of us confirmed the amount of fuel to remain. We noted the time winds and location for both start and stop points. We then continued to ZZZ and mad an uneventful landing and taxied to the gate.
Second reporter narrative
First Officer's forward window heater element glowing; sparking; and delaminating window. Fuel dump to max landing weight for air return.Dispatch and Maintenance Control contacted. All parties agreed an air return to ZZZ appropriate.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.