A former national security official who operated deep-dive submersibles for the US navy said on Tuesday that piloting a vessel like the one that rescuers are searching for in the North Atlantic was like navigating in outer space.

“You are a long way from anything that can give you help,” said Jeff Eggers, a former navy commander who spent four years piloting military mini-submarines that were similar in size to the missing submersible, called the Titan, but more technologically sophisticated. “You’re incredibly reliant on the integrity of the vessel. And you’re dependent on the resources you’ve built into the craft.”

In an interview on Tuesday, Eggers, who retired from the military in 2013 after two decades of service and served as special assistant for national security affairs in the Obama administration, said the public tended to underappreciate the perils inherent in excursions like the one undertaken by Titan, which went missing on Sunday.

Among other things, he said, the civilian-operated submersible appeared to lack significant safeguards that the navy requires, including an escape hatch, so that even if the Titan managed to surface, its occupants would be unable to exit the craft on their own.

Other risks are a constant concern in submersibles, he added, including potential malfunctions with the ballast systems; failures in the vessel’s inner pressure hull, which is shaped like a hot dog and can crack catastrophically under the extreme weight of the ocean; and electrical fires and failures, which tend to knock out the ability to communicate and manoeuvre.

New York Times News Service