Bakunawa

• But their history shows that this is far from the case.
• Bathyspheres were unpowered submersibles lowered into the sea on a cable and used for pioneering dives in the early 1930s.
• Since then, submersibles have taken many more people into the deep ocean than the number of humans who have been into space.
• Fumes from an electrical fire overcame the occupants of a Japanese tethered diving bell at around 10 metres deep in 1974.

Pushing the limits

• The first to do so was a bathyscaphe – a submersible suspended below a float, rather than from a cable like the bathysphere.
• It was called FNRS-3 and it set an overall depth record for the time, reaching 4,050 metres in 1954.
• Over a 14-year period starting in 1991, the two Russian Mir submersibles visited the Titanic wreck than any other vehicle.

Today’s submersible fleet

• But there are currently seven submersibles in service that can reach the depth of the Titanic and beyond.
• There is one very deep-diving submersible in private ownership: the Limiting Factor was built by Triton Submarines for Texan billionaire Victor Vescovo to pilot to the deepest point in all five oceans in 2019.
• The Aluminaut submersible of the 1960s, which was capable of diving to 4,500 metres, had an aluminium hull with a tubular shape that could carry seven people.
• In 2013, I dived aboard Japan’s Shinkai 6500 submersible to study undersea hot springs at 5,000 metres deep on the ocean floor.