The Great Miscalculation: The Race to Save New York City’s Citicorp Tower, by Michael M. Greenburg. New York City: New York University Press, 2025; 264 pages, $27.95.
Gazing up from the corner of Lexington Avenue and East 53rd Street in New York City today, the Citicorp building is – with perhaps some allowance made for modern jaded sensibilities – just as strikingly different as when it was completed in 1977.
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Built on 114-foot-high “stilts,” unusually located at the midpoint of each side rather than the corners to accommodate the relocation of a church displaced by the construction, the Citicorp Tower looks precarious to the untrained eye. And as originally built, it actually was precarious but not exactly for the reasons it appears.
In The Great Miscalculation, practicing attorney and accomplished author of four previous books, Michael M. Greenburg, opts to write about this building not merely for its unusual structural design but for a flaw in the implementation and construction of that design. As a cost-saving measure, the connecting joints for diagonal wind-brace members, which the design had specified be secured with full-penetration welds, had been replaced with bolts.
This was later acknowledged to be a “perfectly reasonable request” from Bethlehem Steel under normal circumstances – which unfortunately did not describe the Citicorp design. The result was a building that could collapse under certain wind loads that were far from improbable.
Greenburg’s account examines in reportorial detail how the change was discovered and its full meaning on the tower’s structural integrity – understood only after the building was completed and occupied – and the subsequent race to fix it.
How urgent was the need? The structural engineer who designed the building, William LeMessurier, ultimately calculated that the building had a 1 in 50 annual chance of toppling in a strong diagonal (or “quartering”) wind. Worse, if the tuned mass damper incorporated into the design was not functioning – entirely possible during a power loss caused by a significant storm – then that chance rose to 1 in 16 annually.
Other than to explain that the flaw was fixed by the end of 1978 – quietly and during the night – using welded steel bracing, this piece will not spoil the drama of all that transpired to get to that point. This included two unrelated calls from students to the structural engineering firm that helped prompt a closer look at the engineering and wind loads, a hurricane that briefly threatened to hit New York that fall, the city’s plan to evacuate the building in the event that high winds threatened, the lead engineer’s simultaneous disclosure of the flaw once discovered while also being complicit in keeping the danger publicly quiet, and much more.
The book remains compelling even after the discovery and rectification of the error, as it remained largely unknown to the public and even within the building community until 1995. The events have prompted significant discussions surrounding the professional ethics of the situation, with LeMessurier being both hailed and criticized for his actions.
Throughout, Greenburg’s writing stokes the reader’s interest, not via any tendency to sensationalism but simply by slowly and expertly unspooling the carefully researched facts to tell this story. His “day job” expertise shows in an examination of the legal wrangling over the matter, which was ultimately settled out of court.
The Great Miscalculation, in the end, masterfully blends discussion of complex structural engineering concepts, the risks and realities of significant construction projects, and the ethical standards to which engineers must hold themselves.
