PUERTO RICO — The wreckage of Pan Am Flight 256, the Clipper Endeavor, was discovered on the ocean floor off the coast of Puerto Rico in June 2026. The aircraft was located approximately 2,000 feet below the surface of the ocean.

The search team used an autonomous underwater drone equipped with sonar to locate the wreckage. The autonomous underwater vehicle used in the search is named Miss Millie. The search vessel used was the Fugro Brasilis.

The search team narrowed the search area to 10 square nautical miles. The wreckage was found on the evening of June 2, 2026. The aircraft was identified by images showing the Pan American logo and the name 'Clipper Endeavor.'

The Clipper Endeavor crashed into the Atlantic Ocean on April 11, 1952, shortly after takeoff from San Juan, Puerto Rico, while en route to New York. The flight carried 64 passengers and five crew members. The pilot of the Clipper Endeavor was John C. Burn.

John C. Burn was a crew member on the Pan Am seaplane Yankee Clipper, which crashed near Lisbon, Portugal, in 1943. The plane lost both right-side engines shortly after takeoff. All 69 passengers and crew members survived the initial impact of the crash. The plane sank in less than three minutes after hitting the water. Fifty-two people died and 17 survived the 1952 crash of the Clipper Endeavor. The USS Yorktown and other rescue assets saved 12 passengers and five crew members. The two known living survivors of the crash have been contacted about the discovery. One of the two known living survivors is a 102-year-old woman who was a nurse at the time of the crash. The other known living survivor was a baby at the time of the crash who was found floating and resuscitated. The crash of the Clipper Endeavor led to mandatory pre-flight safety briefings on commercial flights.

John Cox is an aviation safety expert and founder of Safety Operating Systems. He said the crash became a catalyst that helped drive safety improvements such as better flotation equipment and preflight briefings, calling it a steppingstone in the development of modern aviation safety and a rallying cry at the time. Gates said the accident fundamentally reshaped aviation. He said every traveler today owes a debt to what happened to the Clipper Endeavor, noting that current safety practices like exit demonstrations and flotation device instructions did not exist before the crash, which contributed to the drowning of 52 people amid chaos. Gates described seeing the bright aluminum fuselage reflecting sonar images from the ocean floor as a hugely emotional and staggering moment, emphasizing the aircraft’s remarkable preservation. He said the discovery honors the legacy of those aboard and reminds the public of the debt of remembrance owed to the flight. He also expressed gratitude for being part of the expedition, noting that technology only recently advanced enough to reach the wreckage. Matthews said the technology to locate the plane was out of reach in 1952 and only now has caught up. He said the team is stunned, elated, and humbled by the discovery.

The discovery of the Clipper Endeavor provides a tangible connection to a pivotal moment in aviation history. The crash led to mandatory pre-flight safety briefings on commercial flights, a standard that remains in place today. The Air/Sea Heritage Foundation is advocating for a memorial to honor those who died in the crash.

The two known living survivors of the crash have been contacted about the discovery. The Air/Sea Heritage Foundation is working with the government of Puerto Rico to expand protections for the wreck site. The Discovery Channel will feature the discovery in an episode of 'Expedition Unknown' later in 2026.