

On the morning of August 29, as the two were getting ready to be towed back to their mother ship, a hatch was accidentally pulled open. They were clocking eight-hour shifts, crammed into a small vessel with very poor visibility, according to the BBC. Former Royal Navy submariner Roger Chapman, who died in 2020, was 28. Senior pilot Mallinson, an engineer, was 35 at the time. It was August 1973, and two British sailors were heading out on a routine dive to lay transatlantic telephone cable on the seabed about 150 miles southwest of Cork.

"You just rely," he said, "on the thing being well-made." The submersible after a routine dive One of them, Roger Mallinson, told NBC News on Tuesday that the search for the Titan has evoked tough memories of his own experience. In that dramatic incident, two crewmen - both named Roger - spent three days trapped in a vessel measuring 6 feet in diameter, subsisting off a single sandwich and condensation licked from the walls, until they were rescued with just 12 minutes of oxygen to spare. National 'Tiny sub, big ocean': Why the Titanic submersible search is so challenging
