The Hyatt Regency walkway collapse killed 114 — a 'simplified' connection

On July 17, 1981, two suspended walkways at the Hyatt Regency Hotel in Kansas City collapsed during a dance competition, killing 114 people and injuring 216. It was the deadliest structural collapse in US history at the time.

The cause was a design change made during construction. The original design had the fourth-floor walkway suspended from the ceiling, with the second-floor walkway suspended from the fourth. The steel fabricator proposed a 'simplification': both walkways would be hung from the same set of rods. This change doubled the load on the fourth-floor connection, which was already at the limit of its capacity.

The change was approved by the engineering firm without adequate review. The connection failed under the weight of the crowd. The case became a landmark in engineering ethics: the engineer of record is responsible for reviewing all design changes, and a 'simplification' that doubles the load is not a simplification — it is a different design that requires a new analysis.