The wreckage of a Pan Am plane that crashed 74 years ago, an incident that spurred the development of mandatory passenger safety briefings on commercial flights, has been discovered off the coast of Puerto Rico. Explorers located the fuselage and tail of the DC-4, known as the Clipper Endeavor, in approximately 2,000 feet of water last month using an autonomous sonar drone.

The 1952 crash resulted in the deaths of 52 people. Survivors reported that while the plane's initial landing on the water was successful, panic ensued. Passengers struggled to locate life vests, and crew members had difficulty deploying rafts as the aircraft rapidly sank. The incident was a significant catalyst for improving aviation safety, leading to advancements in flotation equipment and the implementation of preflight safety demonstrations.

"This one became a catalyst, and it helped drive safety steps forward of better flotation equipment and the preflight briefings," said aviation safety expert John Cox. "So this is one steppingstone along the path to what we today enjoy as aviation safety. It was a rallying cry at the time."

The discovery may offer a glimmer of hope for families seeking answers in other unsolved ocean crashes, such as the disappearance of Malaysia Airlines Flight 370 twelve years ago with 269 people on board.

Russ Matthews began investigating the Clipper Endeavor's fate in 2019 after finding a luggage tag from the flight washed ashore in Florida. Years of research involving archives from Pan Am Airlines, the Coast Guard, and records from the Civil Aeronautics Board, the predecessor to the Federal Aviation Administration, followed. Key information came from a hearing held in Puerto Rico and a map created by Air Force pilots who had witnessed the crash during a training flight.

An earlier attempt to locate the wreck in 2024, documented by the Discovery Channel's "Expedition Unknown," was thwarted by bad weather. Matthews and volunteers from his Air/Sea Heritage Foundation planned a second attempt using advanced, military-grade drones before the 75th anniversary of the crash next year.

Tony Romeo, CEO of undersea exploration firm Deep Sea Vision, had previously discussed the possibility of assisting Matthews. When one of his ships, equipped with the necessary advanced underwater drone, happened to be passing Puerto Rico between other jobs in April, the team seized the opportunity. "There we were, and everything kind of came together at the moment: good weather, the right team, and the right equipment and ship. So we took a shot at it," Romeo said.

Deep Sea Vision had previously conducted an extensive but unsuccessful search for Amelia Earhart's aircraft. Romeo had a personal connection to the Pan Am case, as his father had been a mechanic and pilot for the airline. The drone used in the search even bore a Pan Am sticker.

Matthews' group's research, combined with weather data from the time of the crash, helped narrow the search area to 10 square nautical miles. The drone located the wreckage on its initial pass, with the discovery confirmed when the data was retrieved. The find will be featured in a special episode of "Expedition Unknown" this fall, with released highlights showing the moment of discovery in the control room, marked by exclamations of disbelief and excitement.

"To have a front-row seat to an expedition like this as it's unfolding is tremendous, and so I feel really lucky that we were able to be a part of it," said Josh Gates, host of the show.