Missing Titanic sub: Lawsuit documents show employee said prototype testing posed 'extreme danger'

OceanGate, whose tourist submersible is currently the centre of a large-scale search and rescue operation in the North Atlantic, was repeatedly warned there might be catastrophic safety problems posed by the way it was developed.

Documents show an ex-director of marine operations at OceanGate, David Lochridge, wrote an engineering report in 2018 that the craft under development needed more testing.

Passengers might be endangered when it reached "extreme depths," the report also said.

OceanGate sued Mr Lochridge that year, accusing him of breaching a non-disclosure agreement, and he filed a counterclaim alleging that he was wrongfully fired for raising questions about testing and safety.

The case settled on undisclosed terms several months after it was filed, and a spokesperson has said the missing sub was completed in 2020-21, so it would not be the same as the vessel referenced in the lawsuit.

With five people aboard the vessel and an oxygen supply rapidly running out, an expanding international fleet of ships and airplanes is searching for the Titan.

It is designed to carry five people, a pilot and four passengers, and it is made of carbon fibre and titanium.

About the size of a mini-van, it measures 6.7 meters in length and is designed to reach depths of 2.5 miles (4 kilometers).

Mr Lochridge's concerns primarily focused on the company's decision to rely on sensitive acoustic monitoring - cracking or popping sounds made by the hull under pressure - to detect flaws, rather than a scan of the entire hull.

He said OceanGate Expeditions told him no equipment existed that could perform such a test on the 5-inch-thick (12.7-centimeter-thick) carbon-fiber hull.

"This was problematic because this type of acoustic analysis would only show when a component is about to fail - often milliseconds before an implosion - and would not detect any existing flaws prior to putting pressure onto the hull," Mr Lochridge's counterclaim said.

A sudden implosion, which would kill all five crew members instantly, has been a concern for experts monitoring the situation - but "banging sounds" detected by sonar technology, confirmed on Wednesday, has given cause for hope the vessel is still in tact.

Further, the craft was designed to reach depths of 4,000 meters (13,123 feet), where the Titanic rested.

But, according to Mr Lochridge, the passenger viewport was only certified for depths of up to 1,300 meters (4,265 feet), and OceanGate would not pay for the manufacturer to build a viewport certified for 4,000 meters.

Concerns were raised over acoustic monitoring of the hull, as well as the passenger viewpoint

OceanGate's choices would "subject passengers to potential extreme danger in an experimental submersible," the counterclaim said.

However, the company said in its complaint that Mr Lochridge "is not an engineer and was not hired or asked to perform engineering services on the Titan."

He was fired after refusing to accept assurances from OceanGate's lead engineer that the acoustic monitoring and testing protocol was, in fact, better suited to detect any flaws than a scan would be, the complaint said.

OceanGate Chief Executive Stockton Rush defended the approach in a speech to a conference in Seattle last year hosted by the tech news site GeekWire.

He described how he had taken a prototype down to 4,000 meters: “It made a lot of noise,” he said.

So he brought the vessel back up, and on a second dive it made the same troubling noises, even though it should have been dramatically quieter.

The company scrapped that hull, which had been constructed by a marine manufacturer, and built another one with an aerospace supplier, Mr Rush said.

OceanGate also received another warning in 2018, this one from the Marine Technology Society, which describes itself as a professional group of ocean engineers, technologists, policy-makers and educators.

In a letter to Mr Rush, the society said it was critical that the company submit its prototype to tests overseen by an expert third party before launching in order to safeguard passengers.

Mr Rush, who is on board the vessel that is now missing, had refused to do so.

In a 2019 interview with Smithsonian magazine, the OceanGate founder complained that the industry’s approach was stifling innovation.

"There hasn’t been an injury in the commercial sub industry in over 35 years," Mr Rush said.

"It’s obscenely safe because they have all these regulations... But it also hasn’t innovated or grown - because they have all these regulations."

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