United Flight Returns to Phoenix After Crack in Window

Cracked windscreens is an unfortunate common event generally caused by the window defrost system overheating the window. General cause for this is pilot failure to turn off when not needed or a short in the window. Happened quite a lot to planes I worked on when I was in the Air Force. No one was in any danger as the window is a part sandwich. Generally, and I never saw any other failure, only one pane of the sandwich cracks.

The reason for the pilots declaring an emergency is because of the inability of both pilots to have a clear view of the space ahead of them. generally speaking..

Was on a United from EWR to CHS in April, same deal. Windscreen was totally spyder webbed on left side. Already at cruise, diverted to RDU. Different aircraft, mine was an Embraier.