William M. Greenburg

A new book contains never-before-released details of the flawed structural engineering design and construction of the Citicorp Center high-rise in Manhattan and the secret nighttime repairs carried out in the summer of 1978. 

The episode remained a secret until a New Yorker magazine article in 1995, after which it became a touchstone in engineering ethics education based on the actions of structural engineer William LeMessurier. 

Alerted by inquisitive students unconnected to the project team who puzzled over the design, LeMessurier finally realized the danger—a one-in-16 chance of failure if exposed to powerful winds acting diagonally on its sides. He subsequently consulted other engineers, informed the building owners of the problem and saw repairs through to completion.

The author, attorney and popular historian William M. Greenburg, now shows more of the less-flattering, behind-the-scenes machinations and motives than did the New Yorker article or subsequent stories in ENR. The resulting narrative is thus more complex than the magazine article and diminishes some, but not all, of the honor associated with LeMessurier’s painstaking admission of fault.

LeMessurier, who died in 2007 at age 81, is the center of the action. But there is much rich context—of New York City in the 1970s and the role of failure in structural design progress.

In researching The Great Miscalculation: The Race to Save New York City’s Citicorp Tower (NYU Press: $27.95), Greenburg dug into a private file of LeMessurier’s as well as notes made by writer Joe Morgenstern for his New Yorker article, headlined “The Fifty-Nine-Story Crisis.” Greenburg describes the unusual innovative design, arising from the need to keep in place a small church on the site. The engineer cantilevered part of the steel-framed tower over it. Greenburg writes in detail about the roles of two students, one in architecture and another in engineering. The engineer, Diane Hartley, in particular never spoke to LeMessurier but raised issues that finally alerted him to his failure to consider the possibly devastating loads that could be imposed by the diagonal, or quartering, winds.

Greenburg’s fresh reading of the material and his interviews with LeMessurier’s relatives and associates provide many new insights into the engineer’s inner turmoil and motives, most controversially, in helping hide the nature of the repairs from the public—and ENR—saying it was justified at the time to avoid a panic.

Greenburg found the main file record kept by LeMessurier, labeled Project SERENE, an acronym for Special Engineering Review for Events No One Envisioned, at Harvard University’s Graduate School of Design, where the engineer’s papers are held. Morgenstern graciously provided Greenburg his interview notes from the 1995 New Yorker article.

Adding to the Citicorp Tower Story

In a phone interview from Massachusetts, Greenburg described his approach. “I wanted to add something new,” he said. Until then, the Citicorp tower story “focus was more on ethics and the professional responsibility aspects of the case, but most readers will find that I try to focus more on human interest rather than engineering details,” said Greenburg,

Among many interviews blended into the narrative are several that question LeMessurier’s judgment in his design and the design and construction process. 

There are also less-than-flattering comments from his firm’s former New York City office manager, who, having joined the firm after the work was done, complained that he was unfairly perceived as having something to do with the errors. A member of a New York City-based engineering joint venture partner with LeMessurier’s firm is quoted as saying that LeMessurier’s firm was responsible for the basic design concept and critically important switch by the steel construction team from the original design’s welded wind brace connections to bolts. Without that change, there would have been no emergency. LeMessurier claimed not to have been consulted about the change. 

That switched connection may be the key to what occurred. But the fragmented building process that let it go by (LeMessurier had said he never knew who performed calculations for the switch) could be as much to blame. 

One of the most innovative skyscrapers in a city filled with them, known for its angled crown that was part of a design by architect Hugh Stubbins—the project seems to have been constructed with a stricter separation between design and construction than would be needed on a brilliant, pioneering design. The needed teamwork among LeMessurier’s Cambridge, Mass.-based practice, his New York City-based joint venture engineer and the steel erector and prime contractor, also appeared to be lacking and reminiscent of what occurred in the failure of the Kansas City Hyatt Regency walkway collapse in 1981. In that deadly tragedy a changed steel shop drawing failed to get the thorough review it needed from a structural engineer.

One may ask where was the engineering review or construction inspection that would have shouted out the presence of the connection switch and communicated it to LeMessurier? Citing a story in ENR, Greenburg notes that LeMessurier “confessed only to not providing sufficient oversight to his personnel during the project.”

LeMessurier and the flawed, fragmented design and construction process in all its dimensions comes across as something less impressive than the heroic ethics lesson about one person. While he was one of the world’s great structural engineers, LeMessurier also understood that the Citicorp tower mistake and repair would be his legacy as much or more than the buildings he designed.

But now with Greenburg’s book the truths and ironies of LeMessurier’s famous confession can be seen, and taught, more completely.