Clipper Endeavor (NC88899)

The search for Clipper Endeavor is an ongoing effort led by Air/Sea Heritage Foundation to find the wreckage of Pan American World Airways Flight 526A that crashed off San Juan, Puerto Rico in April 1952. Locating and identifying the site will allow characterization and protection of this important cultural heritage resource, while hopefully spurring a greater awareness and appreciation for its historical significance.

LOST PAN AM AIRLINER CLIPPER ENDEAVOR FOUND AFTER DECADES BY AIR/SEA HERITAGE FOUNDATION, DEEP SEA VISION, AND DISCOVERY CHANNEL’S EXPEDITION UNKNOWN

HISTORIC CRASH FOREVER CHANGED AVIATION SAFETY  AND LED TO MANDATORY PRE-FLIGHT SAFETY BRIEFING

(New York, NY) – July 21, 2026 – Seventy-four years after crashing into deep water off the northern coast of Puerto Rico, the lost wreckage of the lost Pan American Airways passenger plane Clipper Endeavor has been located following a years-long investigation led by Air/Sea Heritage Foundation (ASHF) and in partnership with Deep Sea Vision (DSV), an Eco Minerals Company, and Discovery Channel’s Emmy® Award-winning series, Expedition Unknown. This landmark discovery sheds new light on the fate of the aircraft whose tragic legacy forever transformed modern air travel.

The Douglas DC-4 aircraft, roughly the size of a modern Boeing 737, was found using high resolution sonar on June 2, 2026, at 7:14pm (AST), broken into two sections and resting almost 2,000 feet under the Atlantic Ocean. A follow up photographic survey of the wreck site provided conclusive identification with images clearly showing the iconic winged Pan American logo and aircraft name still legible on the battered, but largely intact and well-preserved fuselage.

Pan Am’s flight 526A remains one of the worst air disasters in Puerto Rico’s history. On Good Friday, April 11, 1952, Clipper Endearvor departed San Juan’s Aeropuerto de Isla Grande bound for New York’s Idlewild Airport (later John F. Kennedy International Airport), carrying five crew members and 64 passengers. Shortly after takeoff, multiple-engine failures forced the pilot to conduct a violent water landing. All people aboard initially survived the impact, which sheared off the aircraft’s tail but left the main cabin intact. Yet with no safety briefing provided, a significant language barrier, and no coordinated evacuation procedure in place, passengers faced chaos, confusion, and heavy seas as the aircraft flooded and sank in less than three minutes. Despite swift and heroic action by rescue teams from the U.S. Coast Guard and Air Force, only 12 passengers and five crew members were saved; 52 people ultimately lost their lives.

Known in Puerto Rico as “La Tragedia del Viernes Santo” (“The Good Friday Tragedy”), the accident became a pivotal turning point in aviation history, prompting the Civil Aeronautics Board, a forerunner of today’s FAA, to implement sweeping reforms, including the now-mandatory preflight safety briefing and emergency procedure demonstrations that have since saved countless lives.

Due to the extreme water depths, the wreck of Clipper Endeavor remained far beyond the reach of investigators. Almost seven decades would pass before the incident caught the attention of aviation and maritime historian Russ Matthews, President and Co-founder of the Air/Sea Heritage Foundation. Matthews has led and collaborated on numerous expeditions to discover and document significant ship and aircraft wrecks around the globe.

“I first learned about Clipper Endeavor while researching an entirely different Pan Am crash and was astonished that such an important story had largely faded from public memory,” Matthews said, “The story is so powerful and the impact so far reaching. We are all stunned and elated by this discovery yet also humbled to remember what happened in that place so long ago.”

In 2019, Matthews began poring through scattered accident investigation reports and conducting several surveys off the coast of San Juan. A collaboration with explorer Josh Gates of Discovery Channel’s Expedition Unknown for an episode that originally aired in October 2024 led the investigation to the Archivo General de Puerto Rico (General Archives of Puerto Rico) where they later uncovered a treasure trove of long hidden evidence, including emotional survivor testimony, real time communications transcripts, expert analysis and, most crucially, a chart map created by US Air Force pilots who witnessed the crash of Clipper Endeavor and guided rescue crews to the scene. This map further narrowed down the search area.

Then, several weeks ago, the research vessel Fugro Brasilis, while transiting from Trinidad to the Gulf of Mexico, agreed to stop off the coast of San Juan to assist in the search. Onboard was one of the world’s most advanced autonomous

underwater vehicles (AUV), owned by cutting-edge marine survey and mining outfit, Deep Sea Vision, an eco-minerals company. Led by CEO Tony Romeo and President of Operations Craig Wallace, their expert team maintains a pair of Kongsberg Maritime HUGIN AUVs, free-swimming drones equipped with a suite of sophisticated sensors that can be programmed to scan vast swaths of the ocean floor as deep as 6000 meters (20,000 feet), while staying submerged for up to four days at a time. This paved the way for a new expedition to conduct an extensive subsea search that ultimately identified the wreck.

“This discovery offered a rare opportunity to connect with a pivotal moment in history while demonstrating how the proper application of research and cutting-edge technology can unlock even the most elusive undersea mysteries,” said Tony Romeo. 

“Every time you step onboard an airplane today, you are safer because of what happened to Clipper Endeavor and her passengers three quarters of a century ago,” said Josh Gates. “This aircraft vanished beneath the waves, and the legacy of those aboard was at risk of being lost with it. When the images came back from the AUV, we all gasped. Seeing the bright aluminum fuselage shining back at us from the ocean floor was a hugely emotional moment. I hope this historic discovery brings some peace to the families of those aboard and serves to remind the flying public today of the debt of remembrance we owe to this fateful flight.” 

The ASHF team is actively working with the government of Puerto Rico to enact expanded protections for the wreck site and advocate for a lasting memorial honoring those lost. They have also been in contact with many of the families directly impacted by the tragedy, including the accident’s only two known living survivors.

The search for Clipper Endeavor and the full story behind this historic discovery will be featured in a forthcoming episode of Discovery Channel’s Expedition Unknown later this year. For more information about Mission Endeavor 2026 and to view images of the discovery, visit airseaheritage.org.

###

About Air/Sea Heritage Foundation:

Air/Sea Heritage Foundation is dedicated to the study, investigation and preservation of relics, wrecks, sites, and stories related to aviation and maritime history. The foundation conducts or supports original field expeditions and archival research around the world, focused on illuminating our shared nautical and aeronautical past.

About Deep Sea Vision, an Eco Minerals Company. 

Deep Sea Vision provides cutting edge deep ocean survey equipment operated from shore or vessel. The company’s highly knowledgeable and experienced operations personnel deliver quality controlled data and remove the concerns over team and system infrastructure offering flexibility to suit the client. 

About Discovery Channel  

Across every platform, Discovery Channel is dedicated to connecting audiences who have a passion for adventure and crave a connection to the world around them. Popular series including Deadliest Catch, Expedition Unknown, Naked and Afraid and Gold Rush, along with Shark Week, the annual tentpole programming event, serve as trusted portals that transport viewers directly into thrilling, real, high stakes moments. Through smart, authentic characters whose stories inform and inspire, Discovery celebrates the men and women who will stop at nothing to explore new spaces and achieve their dreams. For more information, please visit www.discovery.com 

Discovery Channel is part of Warner Bros. Discovery (NASDAQ: WBD), a leading global media and entertainment company that creates and distributes the world’s most differentiated and complete portfolio of content and brands across television, film and streaming. Available in more than 220 countries and territories and 50 languages, Warner Bros. Discovery inspires, informs and entertains audiences worldwide through its iconic brands and products which also include: Discovery Channel, HBO Max, discovery+, CNN, DC, Eurosport, HBO, HBO Max, HGTV, OWN, Investigation Discovery, TLC, Magnolia Network, TNT, TBS, truTV, Travel Channel, Discovery Turbo, Animal Planet, Science Channel, Warner Bros. Pictures, Warner Bros. Television, Warner Bros. Games, New Line Cinema, Cartoon Network, Adult Swim, Turner Classic Movies, Discovery en Español, Hogar de HGTV and others. For more information, please visit www.wbd.com.