The Hyatt Regency walkway collapse
When three “floating walkways” crashed to the floor of Kansas City, MO’s swank new Hyatt Regency on July 17, 1981, speculation first fixed on the patrons who’d been dancing on them: perhaps their high-stepping had set off a harmonic wave that made the sky bridges buckle and crumble.
The truth proved more prosaic. The hotel’s engineers had originally designed two of the three walkways to hang on common, vertical metal rods. But the metal fabricator took a fatal shortcut, substituting shorter rods hanging from one level to the next. The second-floor walkway thus hung from the fourth-floor, doubling the weight on its connectors. The fabricator claimed to have requested approval for this change; the engineers insisted they weren’t asked, though they had signed off on final drawings that included it. The designers had also asked to be on site during construction, when they might have spotted the change, but were rebuffed by an owner determined to avoid additional expense. When enough patrons filled the walkways, the connections gave way. Thanks to miscommunication and corner-cutting, 114 perished in the deadliest structural failure in U.S. history.