The hidden danger: New York skyscraper had a 1-in-16 chance of collapse, known by one

The narrative about the Citicorp Center skyscraper in New York, an iconic structure with a concealed and almost disastrous design error, stands as a significant illustration of the essential importance of honesty and skill in the field of engineering. For years, the public remained unaware that one of the city’s most recognizable towers was, in truth, a looming disaster awaiting the right storm to occur. This daunting secret was solely known by a single engineer, whose steadfast moral compass ultimately preserved countless lives. The account is a fascinating mix of design arrogance, mathematical accuracy, and the silent bravery of a professional who prioritized public safety above everything else.

The building’s innovative design was its most celebrated feature. Erected in the mid-1970s, the Citicorp Center was an engineering marvel, a bold departure from conventional skyscraper construction. It stood on four massive, nine-story-tall stilts at its corners, a decision made to accommodate a new church on the block. The tower, perched atop these legs, appeared to float above the street. This unique structure, a result of a negotiation with the church to preserve its original location, was lauded for its creativity and architectural daring. The design was seen as a triumphant example of form following function, where a seemingly intractable problem was solved with a brilliant and unconventional solution.

Nevertheless, an essential error was embedded in this innovative design. A young student of civil engineering, during a class assignment, started to doubt the building’s structural soundness. Her evaluation, derived from a theoretical study, indicated that the tower might be susceptible to diagonal winds—those impacting the structure at a 45-degree angle. Traditionally, structural assessments only considered winds striking directly, at 90 degrees. This diagonal wind condition, seen as a rare occurrence, was not included in the building regulations or typical industry standards of the period. However, the student’s findings revealed that with this particular stress, the distinctive design of the building’s joint connections could be strained beyond their limits.

Upon learning about the student’s discoveries, the original engineer responsible for the skyscraper’s design, a talented and esteemed professional named William LeMessurier, took her observations to heart. Known for his careful attention to detail, LeMessurier independently verified the calculations. To his dismay, he found the student was indeed right. He had designed a structure with a significant vulnerability, posing a one-in-sixteen likelihood of catastrophic collapse should a severe hurricane hit New York City. This realization was a profound shock, leading to both a personal and professional crisis that he endured alone. He faced an intense moral conflict: remain quiet and risk a public disaster, or speak up and jeopardize his reputation, his career, and the financial stability of his firm.

LeMessurier chose the path of honesty and responsibility. He made the decision to not only inform his clients and the city’s building department but to also take personal responsibility for the error. This act of courage set in motion a secret, round-the-clock operation to reinforce the building. Working under the cover of darkness, crews welded massive steel plates over each of the skyscraper’s 200 bolted joints. The process was painstakingly slow and dangerous, but it had to be done in secret to avoid public panic and preserve the building’s reputation. The cover story was that the crews were performing routine maintenance, a fabrication that allowed the work to proceed without incident.

The reinforcement initiative was a battle against the clock. Hurricane Ella, a formidable storm, was progressing along the East Coast. As the hurricane advanced, LeMessurier collaborated with government officials to prepare for a possible evacuation, a backup plan that, thankfully, never needed to be executed. The storm turned out to sea, and the discreet repairs were finished without the public ever realizing the peril they had been in. The tale of the Citicorp Center stayed concealed for almost twenty years, only becoming known when a journalist discovered the specifics. LeMessurier, who had retired, was finally able to recount the entire narrative of his choice, solidifying his legacy not only as a skilled engineer but also as a genuine professional who embodied the highest ethical standards.

The tale of the Citicorp Center is a valuable lesson in the importance of structural integrity and the ethical responsibility of those who design the buildings we inhabit. It underscores the fact that even the most brilliant minds can make mistakes, and that the true measure of a professional is how they respond to them. William LeMessurier’s actions stand as a monument to the principle that public safety must always come before personal gain or professional pride.

His courage to face the consequences of his error and to act decisively to fix it is a powerful reminder that the buildings that shape our cities are not just monuments of steel and glass, but a reflection of the integrity of the people who build them. The story has been used as a teaching tool in engineering schools for decades, serving as a powerful case study in ethics and a cautionary tale about the importance of re-checking one’s work.