Surviving in air bubble, using Morse code: Incredible underwater rescue missions from the past

The US Coast Guard has detected banging sounds in the North Atlantic Ocean while searching for the Titanic expedition submarine that went missing on Sunday. As rescuers race against time to save five people on board the technologically advanced submersible called Titan, we take a look at some of the incredible underwater rescue operations of the past.

Pisces III submarine rescue

In August 1973, Royal Navy submariner Roger Chapman and engineer Roger Mallinson spent three days trapped in a commercial submarine named Pisces III after it sank 1,575 ft off the coast of Ireland. The two were rescued when they had just 12 minutes of oxygen left inside the submersible. It is the deepest successful underwater rescue in history, according to Daily Mail.

Chapman and Mallinson were laying a phone cable in the Atlantic Ocean off the coast of Cork in Ireland. When the submersible was being brought to the surface, a hatch broke and water started entering inside a portion of the craft, which eventually sank to the bottom of the ocean, the report added.

The two sent a telephonic message, saying they survived the impact and were fine. However, with limited oxygen inside the vessel, the two stopped talking and remained still on the floor. From using submarines to planes and helicopters, the rescue operation team had put everything to use to bring them back. Three days after the incident, the Chapman and Mallinson’s submarine was brought to the surface and the duo was rescued. To this day, it is the deepest successful underwater rescue in history, according to Daily Mail.

Commenting on the search for Titan, Mallinson, 85, has told the Sky News: "I can't understand why they haven't transmitted some signal of some sort. I have a horrible feeling that something might be seriously wrong that they aren't able to transmit a signal."

Squalus rescue

Another famous rescue operation took place in 1939 when the US vessel Squalus with 56 Navy personnel and three civilians sank off US’ east coast. A fault in an air valve led to flooding in the engine room of the submarine. Out of those onboard, 26 drowned while 33 in the forward compartments survived after communicating with Navy rescuers using Morse code. The survivors were brought out of the submarine in a 13-hour operation with the help of a newly developed rescue chamber.

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