He has discovered underwater mountain ranges, strange new species and at least one atomic bomb. And at age 50, Alvin shows no signs of slowing down.

In 1964, Alvin became the first deep-sea submersible capable of carrying passengers, according to the Woods Hole Oceanographic Institution (WHOI), the U.S.-government research centre that operates the vessel.

Alvin was named after WHOI engineer Allyn Vine, who envisioned a research vessel that would allow Americans to explore the bottom of the ocean, just as they were captivated by another engineering challenge: the race to the moon.

Like spacecraft, Alvin was built to withstand extreme pressure. His titanium hull is more than seven metres long and 3.7 metres high, his weight nearly 16,000 kilograms. Two hydraulic arms can lift up to 91 kilograms. Alvin often carries three people at a time; he’s carried 13,000 people so far over his five-decade-long lifespan. After many modifications, he has reached depths of 4,500 metres.

Dave Gallo, a WHOI oceanographer who overcame claustrophobia to take a ride, says it’s like passing through a dream world because of all the bioluminescent animals where one would expect only darkness.

He says Alvin is the most productive submersible in history, having made many discoveries, and that the U.S. “still excels” at going to the sea and “coming back with the goods.”

Some of Alvin’s big discoveries:

  • In 1966, he helped locate and retrieve a hydrogen bomb that had been lost after an American B-52 and a tanker collided over the Mediterranean Sea.
  • In 1977, researchers found the first hydrothermal vents, off the coast of the Galapagos Islands.
  • In 1986, Alvin made 12 dives to the RMS Titanic to test a prototype robotic vehicle called Jason Jr.
  •  Alvin has found 300 new species of animals, including tube worms that can grow up to three metres long.

Alvin may have been the first of his kind, but he has a young competitor who has broken his record: China’s Jiaolong or ‘Sea Dragon,’ has reached depths of 5,555 metres.

However, after a retrofit, Alvin is expected to take the title once again, if he can hit an expected depth of 6,500 metres. No one knows what he’ll find when he reaches that far. After all, only about eight per cent of the deep sea has been explored.

“That other 92 per cent, we could say, ‘well it’s probably empty because we got all that good stuff,’” says Gallo, “I know that’s not true. It’s going to be full of surprises.”

With files from CTV’s Tom Walters