Hyatt Regency walkway collapse

The Hyatt Regency walkway collapse was a tragic engineering disaster that claimed more than one hundred lives and led to numerous injuries. On the evening of July 17, 1981, a pair of walkways suspended over the lobby of the Hyatt Regency Kansas City Hotel in Kansas City, Missouri, collapsed while the hotel was hosting a dance competition in its lavish atrium. Many people were immediately killed. Following the collapse, a prolonged and dramatic rescue effort was undertaken to free survivors trapped under the rubble. In the aftermath of the night’s events, investigators determined that a critical flaw in the walkway’s architectural design was to blame for the collapse. Although no criminal charges were ever filed in connection with the collapse, the responsible engineers and engineering firms lost their licenses, and survivors and victims’ families were rewarded approximately $140 million in damages. Until the September 11, 2001, terrorist attacks that took down the World Trade Center, the Hyatt Regency walkway collapse was the deadliest structural collapse in American history.

Background

In 1910, Kansas City became home to the corporate headquarters of the Hallmark greeting card company. At the time, the company’s headquarters were located in what was then the population center of the Kanas City metropolitan area. Gradually, however, the city’s population center shifted to the south, and the area surrounding the Hallmark corporate headquarters slowly transformed into little more than dilapidated slums. In the 1960s and 1970s, Hallmark undertook a project to reinvigorate the property around its headquarters and turn it into a commercial complex known as the Crown Center. The anchor of the Crown Center was to be a towering 40-story Hyatt Regency hotel.

Plans for the Hyatt Regency Kansas City Hotel were first developed in 1976. The hotel’s design included a 35-story guest room tower and a 4-story conference center. The two buildings were to be connected by a trio of walkways suspended above the lobby atrium at the second, third, and fourth floors. When completed, each of these walkways measured about 121 feet in length and weighed more than 63,000 pounds. They were supported primarily by tie-rods connected to the atrium ceiling and were positioned so that the fourth-floor walkway was located directly above the second-floor walkway.

Construction of the hotel got underway in May 1978. While work on the project for the most part proceeded smoothly, one incident proved to be something of an omen of things to come. On October 14, 1979, part of the atrium roof collapsed during construction. Ultimately, the damage was repaired, and the atrium was deemed safe. Upon the completion of construction in July 1980, the hotel was officially opened for business.

The Hyatt Regency Kansas City Hotel was an immediate hit. Among the most popular events held at the hotel were a series of dance competitions referred to as the Tea Dance. These Tea Dance events—which were held in the atrium—drew thousands of people to the hotel to compete and watch performances as a full orchestra played live music.

Overview

On July 17, 1981, the Hyatt Regency Kansas City was hosting a Tea Dance in the atrium with more than 1,600 people in attendance. By 7:00 p.m., hundreds of people were gathered on the atrium floor. About 40 spectators were standing on the second-level walkway, while 16 to 20 people were watching from the third- and fourth-floor walkways. A short time later, the fourth-floor walkway collapsed onto the second-floor walkway and both crashed to the atrium floor. Approximately 111 people were immediately killed, and many others were injured. A number of survivors were left pinned in the rubble. To make matters worse, several water pipes were severed during the collapse, and water was flowing into the atrium. Because these pipes were connected to tanks instead of the city water supply system, there was no way to stop the flow of water. This meant that those who were trapped also faced the risk of potential drowning until the lobby’s front doors were broken open to release the water.

First responders from across Kansas City quickly arrived at the hotel and began a concerted rescue operation. In addition to treating the injured, these rescuers worked to free those who were pinned by or trapped within the debris. Triage centers were set up to help facilitate the treatment of victims pulled from the rubble of the fallen walkways. A makeshift morgue was also assembled to temporarily house the remains of deceased victims. In total, the entire rescue operation took about 14 hours, and 29 survivors were pulled from the wreckage. The final death toll was 114.

In the aftermath of the accident, investigators immediately began searching for answers about what caused the collapse. Their findings revealed that the main problem resulted from a change in the original design of the tie-rods that connected the walkways to the ceiling. The original design called for the second- and fourth-floor walkways to be connected to the ceiling using three sets of continuous tie-rods to which both walkways would be attached. This meant that the tie-rods in question would have to be threaded along their entire length. The manufacturer of the tie-rods had apprehensions about this design, fearing that the rods would be rendered useless if they incurred any damage during installation. As a result, the manufacturer altered the design so that two separate and offset sets of tie-rods—one connecting the fourth-floor walkway to the ceiling and one connecting the second-floor walkway to the fourth-floor walkway—could be used instead of continuous rods. What went unnoticed was that this approach meant the box beams supporting the weight of the fourth-floor walkway would also have to support the dead weight of the second-floor walkway. In the original design, the box beams on each floor would only have to support the weight of one walkway. Since the fourth-floor walkway box beams simply could not support the weight of two walkways, the design was critically flawed.

Legal proceedings tied to the walkway collapse eventually led to survivors and victims’ families receiving about $140 million in damages. Many of the engineers and engineering firms involved in the design and construction of the walkways had their licenses revoked as punishment. Shortly after the collapse, the Hyatt Regency removed the original third-floor walkway and installed a single new walkway supported by columns. Years later, ownership of the hotel was taken over by Sheraton. A memorial honoring the victims of Hyatt Regency walkway collapse was installed at the hotel in 2015.

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