Will the Titanic sub disaster tank submersible tourism?

Annita Thomas felt nervous about her first submersible dive in the Sea of Cortez, off California's coastline, in April. The worry dissipated quickly as the seven-passenger underwater vehicle dipped below the surface, leaving behind the Scenic Eclipse discovery yacht. The sound of the pilot transmitting periodic safety checks was a comfort amid the thrill.

"I'm really glad I did it," says the on-air host of "Travel With Annita," recalling the 360-degree views of the sea bottom from the submersible's transparent acrylic hull, at a depth just shy of 1,000 feet. "I don't think I would do it now," she adds, citing the implosion of OceanGate Expedition's Titan.

The loss of five lives on the Titan has thrown into question the safety of underwater expeditions: Could this be the end of deep-sea tourism?

In 2023, submersible tourism has become more common than it might sound. Personal submersibles are used widely to explore pristine coastlines, arctic waters and coral reefs. They rarely achieve depths greater than 1,000 meters — 3,280 feet. Titan was intended to descend four times as far.

"No one has yet said, 'Submersible tourism is a bad idea, let's cancel it,' " says Charles Kohnen, co-founder of the pioneering California-based SEAmagine Hydrospace. Kohnen and his co-founding brother William designed and built the first known personal submersibles in the 1990s, offering hourlong trips off the coast of California.

"There's a difference between flying an experimental airplane vs. flying an FAA-approved airplane," Kohnen says in reference to the fact that OceanGate's sub operation lacked certification.

People are asking questions as a result of the Titan's implosion, says Erik Hasselman, commercial director at Netherlands-based U-boat Worx, whose submersibles are used on private yachts and luxury cruise lines. Its clients include Seabourn Cruises and Viking Cruises. But so far, he says, he hasn't seen cancellations.

"We have to see the longer-term effects, but business is continuing here as normal," he explains, adding that the demand for personal submersibles has been growing. U-boat Worx's vessels are luxury products, after all. They are the ultimate yacht toy, capable of descending about 1,000 meters.

So far, there are a handful of ways to book this type of trip. In Curaçao, you can take a 60- to 90-minute dive (starting from $350), from U-boat Worx's local substation, to see panoramic views of vibrant coral reefs or shipwrecks. In the Bahamas, you could shell out a cool $700,000 for Kensington Tours' 10-day yacht tour, which includes daily submersible dives from the Lionshare tri-deck motor yacht.

Perhaps easiest, you can take excursions on expedition ships from luxury cruise lines. For instance, guests on Viking Cruises' Octantis and Polaris ships can sign up for tours that explore the depths of Antarctica or the Great Lakes, among other places, on U-boat Worx subs.

All are limited to the same 1,000-meter threshold. Lower depths, says Kohnen, become "big stuff" that requires a different type of vessel — a metal hull with portholes, rather than a completely transparent bubble.

All of the vessels from SEAmagine, U-boat Worx and Florida-based Triton Submarines are certified by ship classification societies in their home countries. U-boat Worx says it receives an annual visit from its classification body, which is based in Germany, to check all its systems and logbooks and to ensure that maintenance has been done correctly. This includes performing safety dives, Hasselman says. "Then you'll get a stamp, and you're good to go for another year."

Passing the test marks a vehicle as "formally classed" and inspected. It's also worth checking the number of dives a company has completed; the figure surpasses 12,000 for SEAmagine, for instance, while OceanGate's Titan had just 13 dives.

Another big difference: Leisure submersibles are buoyant. They use propellers to drive the vessel underwater, rather than having to fall like a rock and using ballast tanks for stabilization, as with the Titan. "If you lose power and everything shuts off, [personal submersibles] will always float back to the surface," says Kohnen.

The challenge now for the industry will be marketing these trips in such a way that addresses misconceptions without stoking fears of future disasters.

The next generation of personal submersibles is doubling down on luxury. SEAmagine is expecting delivery in January of its ultra-high-end Aurora-90 five-seater. With a 90-inch viewing sphere, it will have a roomier passenger cabin that will feel properly upscale, with leather seating, an interior sound system and air conditioning.

Further off is the $27 million Nautilus underwater superyacht from U-boat Worx. This yacht-sub hybrid will have all the swish features of a luxury boat, including a bar, Jacuzzi, sun deck and a swimming platform. True to its name, this will be a proper yacht — albeit one capable of traveling 500 feet underwater.

Kohnen hopes one thing is clear about the tragedy that unfolded near the Titanic: It wouldn't have happened if OceanGate had adhered to the standards that the rest of the industry follows. In 2018, his brother William Kohnen, chair of the U.S. Marine Technology Society's Manned Underwater Vehicles Committee, addressed a letter to OceanGate's late CEO with a prescient warning.

"The MUV industry has earned itself an enviable safety track record over the past 40 years," he wrote, crediting "the collective observation of (and adherence to) a variety of safety standards." If these were disrupted, he continued, it could "have serious consequences for everyone in the industry."

Charles Kohnen adds that plenty of vessels have been capable of making the journey deeper than 4,000 meters — with proper standards.

"It's not that we're pushing the boundary of technology," he explains. "This whole thing was 100% avoidable."

The Star Tribune added information to this report.