On June 24, 1975, Eastern Air Lines Flight 66 was on approach to New York’s JFK Airport when it encountered something pilots at the time had little way of detecting: a powerful downburst.

As the plane descended through stormy skies, a sudden microburst of wind forced it violently downward. Just moments from landing, the aircraft crashed short of the runway, killing 113 of the 124 people on board.

At the time, the idea that a thunderstorm could create small but intense pockets of wind capable of bringing down a commercial jet was not fully understood or widely acknowledged. But this crash changed that.

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Investigators later determined that the aircraft flew into a localized burst of sinking air that rapidly transitioned into a tailwind near the ground – an atmospheric hazard now known as a downburst, and more specifically, a microburst, which is a downburst on a much more localized scale (covering an area 2.5 miles or less).

The Eastern 66 crash wasn’t the first weather-related accident of its kind, but it was the one that finally led to sweeping change.

In the wake of the tragedy, meteorologists, engineers and the FAA worked together to develop the Low-Level Wind Shear Alert System (LLWAS)a ground-based network of sensors that could detect dangerous wind shifts around airport runways. The system was eventually installed at major airports across the U.S., becoming a critical tool in aviation safety.

Today, downbursts are better understood, and pilots are trained to recognize and respond to them. But it was this crash, on a stormy summer day in 1975, that turned a hidden weather hazard into a turning point for aviation forecasting.

Jennifer Gray is a weather and climate writer for weather.com. She has been covering some of the world's biggest weather and climate stories for the last two decades.