Driving about 65 mph on interstate highway, partly cloudy day, 70-75 F. heard cracking sound, like crumpling aluminum foil for a few seconds before a loud explosion of overhead tempered glass sunroof and glass falling down on us. Not aware of any road debris hitting car or windshield prior to incident. Heard no object hit sunroof before glass cracking sound. No evidence afterwards of road debris damage to any car surfaces or windshield. Cause of failure may be large size of highly stressed tempered glass in conjunction with rigidity/flexibility of surrounding support structure, internal defect, or edge flaw.

- Manning, SC, USA