The submersible that first took humans to the Titanic wreck has made more than 5,000 dives. A researcher who has been on the Alvin 53 times says it's nothing like the Titan.

Erin Snodgrass
Sat, July 15, 2023 

The Alvin is a three-person sub owned by the Navy and operated by Woods Hole Oceanographic Institute.

QAI Publishing/Universal Images Group via Getty Images

Alvin is one of the oldest deep-sea submersibles and is responsible for many scientific discoveries.


Lisa Levin, an oceanographer, told Insider that Alvin missions are different from underwater tourism expeditions.


"It would be like comparing a commercial airline to somebody who built their own airplane," she said.

The presumed implosion of the Titan has prompted a sudden societal interest in the science behind submersibles as the trials and tribulations of the Titan sub's operation are unearthed in the aftermath of the tragedy.

But not all underwater vessels are created equally, one veteran oceanographer told Insider.

Lisa Levin, a marine ecologist at the University of San Diego's Scripps Institution of Oceanography, has taken dozens of deep-water dives on various submersibles throughout her scientific career.

There's one sub that stands above the rest: Alvin.

"Alvin is better than most of them in terms of being very reliable, safe, and getting a lot of work done," Levin said. "It's probably contributed more to deep sea science than any other submarine out there."

The three-person sub is one of the oldest deep-ocean submersibles, commissioned in 1964. The famous vessel is perhaps best known for taking the first humans to the Titanic shipwreck in 1986 when oceanographer Robert Ballard led a research expedition to the wreckage just one year after it was discovered approximately 12,500 feet deep off the coast of Newfoundland.

The spherical sub boasts seven reversible thrusters and two robotic arms, and it can reach four miles beneath the surface, giving researchers access to 99% of the ocean floor, according to Woods Hole Oceanographic Institution, the nonprofit research facility that operates the Navy-owned sub.

Alvin has been on more than 5,000 dives and is the vessel responsible for several advancements in scientific research and discovery, including the 1966 recovery of a hydrogen bomb that was dropped nearly 3,000 feet deep in the Mediterranean Sea after an Air Force B-52 collided with a tanker aircraft over Spain; the 1974 close-up photography of the Mid-Atlantic Ridge, which is part of the longest mountain range in the world; and the 1977 discovery of diverse wildlife in the warm water vents of the Galapagos Islands

But for all its achievements, safety is Alvin's top priority, Woods Hole representatives have said.

"There's two things you don't sacrifice in innovation and that's quality and safety," J. Carl Hartsfield, a retired Navy Captain who runs an oceanographic systems lab at Woods Hole and also consulted on the search for the missing Titan last month, told NBC News.

Alvin was first commissioned in 1964 and is one of the oldest deep-sea submersibles.

Alvin is taken apart, inspected, and reassembled every five years and then goes for recertification by the Navy, a representative with Woods Hole told The San Diego Union-Tribune. The most recent set of upgrades was completed in 2021 and included improved visibility, new lighting and imaging systems, improved sensors, and a state-of-the-art command and control system.

Engineers at Woods Hole pressure test every piece of equipment on board Alvin, no matter how small, NBC News reported. Approximately 60% of the sub is Navy-certified, including critical safety components like life support and flotation foam, Bruce Strickrott, an Alvin pilot, told The Tribune-Union.

"The sub is built around the idea that we have to come home," Strickrott said to NBC News.

The strenuous precautions in place are reassuring for Levin, who has taken 53 dives on Alvin and said she has never once felt unsafe, even as temperatures turn frigid and lights wane hundreds of meters beneath the surface on her hours-long trips below.

OceanGate, the company that created and operated the doomed Titan sub, has been accused in the aftermath of the vessel's likely implosion of prioritizing innovation over safety. Several industry experts warned OceanGate CEO Stockton Rush about the potential dangers of the Titan's irregular construction and the sub was party to a series of troublesome past expedition perils. OceanGate's website and social media accounts were removed on Friday.

A representative from TrailRunner International who has previously responded to media requests for OceanGate did not immediately respond to a request for comment.

The exploratory vessel most likely imploded last month while on a dive to the Titanic shipwreck with five passengers on board, according to coast guard officials.

From its carbon-fiber hull to its larger pill shape, the Titan diverged from industry standards.

"There's a reason Alvin has been a titanium sphere all of its existence," Levin told Insider.

"When you push it, it wants to stay that shape," Strickrott told NBC News of Alvin.

The Titan operation and other tourist exploration expeditions like it are so different from the research dives Levin and other researchers undertake that she said the two are practically incomparable, despite both taking place on submersibles.

"It would be like comparing a commercial airline to somebody who built their own airplane and flew it and had an accident," she said.

Alvin and Levin's next mission is focused on methane seeps and the chemosynthesis ecosystems they fuel off the coast of San Diego. That expedition later this month will only take Levin and her colleagues down to 1,020 meters, relatively shallow compared to her past experiences on Alvin, she said. But next spring, Levin will ride Alvin deeper than she ever has before off Kodiak Island to examine seeps at 5,500 meters.

She isn't worried.

"For me, I don't think the risk is particularly much more than getting in a car on a freeway," she said.