When A Student Saved Manhattan – The Story Of Citygroup Skyscraper

At the corner of 53rd Street and Lexington Avenue in Manhattan, New York, stands a strange skyscraper. The Citigroup Center soars 915 feet in the sky making it one of the most recognizable buildings due to its slanting top.

It’s not until you walk past the tower that you begin to notice something amazing – the building is suspended in the sky. The tall tower rests on a couple of stilts that are nine stories high. This is where it gets interesting because just a year into its completion, the skyscraper was about to fall.

In 1978, the architect of Citigroup Center, William J. LeMessurier, received a call from a student regarding a grave structural fault that could threaten the building in high winds. The student, Diane Hartley, claimed that the quartering winds could topple the tower.

William took immediate notice and started calculating the impact of high winds on the tower. To his surprise, the student was right. According to new calculations, the building could topple when facing severe storms, which hit New York City approximately every 55 years. A less powerful storm could also easily cut off the power to a tuned mass damper, which stabilizes the building. In this case, the building would sway rapidly causing unthinkable damage.

Jumping into action, LeMessurier and his team worked day and night to do the necessary repairs. They were aided by NYPD, the weather department, and 2500 Red Cross volunteers. It took almost a month to complete the repairs. The repair work was done at night and kept a secret. Luckily, the press was on strike, which didn’t raise any eyebrows and no one asked questions.

The secret was only revealed in 1995 by Joseph Morgenstern, a writer for the New Yorker magazine. Later, the BBC aired a special documentary on the topic, which surprised everyone including the student, Diane Hartley, who didn’t know that her call had saved an iconic skyscraper from falling.