Elon Musk Explains Why the Tesla Cybertruck's Armored Windows Broke On Stage

Elon Musk is still picking up the pieces in the aftermath of his armored glass demonstration gone wrong during the Tesla Cybertruck reveal on Thursday night. Among other hyperbolic features, the Cybertruck promises "unbreakable" windows that combine glass with advanced polymer layered composite material. Unfortunately, they did indeed break when Tesla Chief Designer Franz von Holhausen threw a steel ball at the truck on stage during the live event. And now Musk says he can explain what happened.

Musk took to his favorite social media platform on Sunday night and tweeted that the Tesla Cybertruck's "Armor Glass" was compromised by the prior strength demonstration at the reveal that involved von Holzhausen smacking the door panel with a sledgehammer. Though the hammer caused no apparent effect, Musk is claiming that the blow cracked the base of the glass.

”Sledgehammer impact on door cracked base of glass, which is why steel ball didn’t bounce off. Should have done steel ball on window, *then* sledgehammer the door. Next time . . .” Musk wrote.

To prove his point, Musk also tweeted out a slow-motion video of the steel ball test being performed successfully hours before the live event on Thursday. It's a plausible explanation, though it doesn't account for a couple factors that the Cybertruck's vociferous critics are now wielding against Tesla. One, von Holzhausen only hit the front door with the hammer, so that wouldn't account for the rear window also cracking in what Musk further claims was an impromptu test following the front window's on-stage failure.

And two, there's a growing chorus of people claiming the sledgehammer itself was in fact what's known as a dead blow hammer, a soft-headed mallet that's specifically designed to reduce the chance of unintentional damage. They typically come with orange heads like the one seen on stage. We can't confirm this with video screengrabs and rough comparisons alone, though. 

After the snafu, Musk felt more than just pressure on social media. Tesla stock dropped more than 5 percent on Friday morning, dropping Musk's net worth by a reported $778 million. Of course, this is all relative to someone worth around $23 billion.