Some 74 years after a passenger plane crashed off Puerto Rico, an aviation search team has found the wreckage on the floor of the Atlantic Ocean.

Compulsory emergency procedure demonstrations for commerical flights were introduced in the aftermath of the tragedy.

The Pan American Airways aircraft, named Clipper Endeavor, was located by the Air/Sea Heritage Foundation and others, including Discovery Channel’s series “Expedition Unknown”.

Discovery confirmed the wreckage was found off Puerto Rico’s north coast last month.

The Douglas DC-4 aircraft broke into two sections and came to rest after crashing into the ocean shortly after taking off from the Caribbean island on 11 April 1952.

The 64 passengers and five crew members on board survived the initial impact.

However, just 17 people – 12 passengers and five crew – were rescued as the plane sank.

Pan American plane Clipper Endeavor crashed into the Atlantic Ocean in 1952
Pan Am plane Clipper Endeavor crashed into the Atlantic Ocean in 1952

The disaster led to sweeping aviation reforms, with the introduction of pre-flight safety briefings and emergency procedure demonstrations on commercial flights.

“We are all stunned and elated by this discovery yet also humbled to remember what happened in that place so long ago,” President of the Air/Sea Heritage Foundation Russ Matthews said.

The search, involving the Deep Sea Vision company, used high-resolution sonar, and autonomous underwater drones.

It located the wreckage almost 610m below the surface of the Atlantic.