Narrative:

At cruise the captain side window heating element caught fire and began arcing. The proper protocol as per the QRH was complied with. The window heat was shut off and the window cracked and spidered. The window appeared to continue to arc even with the window heat off. The [advised ATC] and we diverted to [an alternate] with no further incidents.

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Original NASA ASRS Text

Title: B757 First Officer reported diverting to an alternate after the Captain's side window heating element caught fire and the windshield cracked.

Narrative: At cruise the Captain side window heating element caught fire and began arcing. The proper protocol as per the QRH was complied with. The window heat was shut off and the window cracked and spidered. The window appeared to continue to arc even with the window heat off. The [advised ATC] and we diverted to [an alternate] with no further incidents.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.