A former employee of the company behind the Titan submersible, OceanGate, said he believed it was "inevitable" there would be a safety incident as the firm "bypassed" all standard rules
David Lochridge said he had "no confidence" in the way the submersible was built, saying he believed his concerns were dismissed for cost-cutting reasons
The whistleblower was giving evidence to a US Coast Guard hearing into the Titan sub, which imploded in June 2023, killing all five people on board
Lochridge warned of potential safety problems with the vessel as far back as 2018, which he says were ignored
Titan sued him for revealing confidential information, and he countersued for unfair dismissal
Animation shows how sub made descent to Titanic wreckage
As we wait for the inquiry to resume after a break, let's have a look again at a map of the Titan's route and descent to the wreckage site of the Titanic, supplied by the US Coast Guard.
This animation was shown in the hearing.
Titan sub: Animation shows how vessel made descent to Titanic wreckage
Richard Gray
Editor, BBC Future
Image source, Getty ImagesThe wreck of the Titanic lies in total darkness on the seabed, nearly 2.4 miles (3.8km) below the surface.
It is an incredibly hostile environment that makes visiting the wreck a challenge.
Travelling that deep can take time – it is a two-hour-long descent. Below about 3,300ft (1,000m), sunlight is unable to penetrate the water and everything exists in what is aptly named the "midnight zone". It makes it easy to become disorientated without accurate navigation techniques.
As a submersible travels downwards, the pressure exerted on it by the water above also increases. At the depth of the Titanic wreck, the pressure is around 390 times greater than we experience on the surface.
Submersibles travelling to that depth need to be able to withstand these huge forces, and usually have thick metal hulls to do this.
You can learn more about the treacherous waters around the Titanic wreck in this article by BBC Future.
Rebecca Morelle
Science editor
Raising concerns about Titan had serious consequences for David Lochridge.
He’d moved his family from Scotland to the US for the job - a job that he thought would be “a good fit” for him.
But with his role of overseeing safety, he felt he couldn’t stay quiet as the problems with the sub became increasingly clear.
And he didn’t stay quiet - he spoke up repeatedly, even when he knew it would get him fired.
But he wasn’t just fired. He was sued too - and even spent 10 months in a witness protection scheme.
It’s hard to imagine how he felt when he first heard that the Titan sub had failed - just as he’d predicted - knowing the warnings he’d sacrificed so much to make had been ignored.
Image source, US Coast GuardThe entire day is dedicated to David Lochridge's testimony
With the hearing on a break for lunch, let’s review the highlights from today's proceedings of the Titan submersible inquiry so far:
After a short break, Lochridge continues his evidence, describing a time when he and his wife were served a settlement and release agreement from OceanGate's lawyers, "basically threatening us," he says.
OceanGate wanted Lochridge to "walk away" from the OSHA claim, he says, and to pay the company back for the money it spent on a lawyer.
If Lochridge failed to sign the agreement, OceanGate would contact officials including US immigration control, he says.
Those on OceanGate's side of the room say they do not have that letter in front of them, so it's decided that the hearing should take a longer break for lunch to give both sides time to square up their documents.
The hearing is due back at 13:45 local time (18:45 BST). In the meantime, we will continue to bring you analysis.
After his termination, former OceanGate operations director David Lochridge says he was placed under the whistleblower protection scheme for ten months.
He confirms to the hearing that the Occupational Safety and Health Administration (OHSA) had him in witness protection.
I gave them "as much information as I possibly could," he says.
While under witness protection, he had "no interaction" with the US Coast Guard and was told that the OHSA "deal directly with the coastguard on your behalf".
"I thought, in hindsight, I was in good hands with the people that administer health and safety within the US," Lochridge says.
Lochridge is now being asked about the state of the first Titan prototype at the time of his termination in 2018.
He says the company was still waiting for an air cylinder but Rush remained adamant the submersible would launch that year.
Lochridge adds he contacted the Occupational Safety and Health Administration (OSHA) within weeks of Rush firing him to raise his concerns about the safety of Titan.
The organisation acknowledged the issues and set up a meeting between him and their Seattle-based assistant regional administrator.
Lochridge is now asked about Stockton Rush's plan to test the Titan submersible himself, with a manned dive in the Bahamas.
"This was an ego boost for him", says Lochridge, adding that Rush was dismissive of the possible implications of a failed manned testing on the OceanGate team and the wider industry.
Lochridge says he was terminated the next day. He was emailed a letter to say that Rush and he were "at an impasse".
After raising numerous safety concerns to OceanGate, Lochridge says he faced a dismissal meeting lasting more than 2hrs.
The attendees included the company's CEO Stockton Rush; Scott Griffith, OceanGate’s director of quality assurance; Tony Nissan, the engineering director; and Bonnie Carl, the finance and human resources director.
I raised safety concerns with many people, Lochridge says, including the Chief Operating Officer, Neil McCurdy and “even the media and marketing manager”.
In the end, though, only one director agreed with his concern: Bonnie Carl, the finance director.
Speaking of other experienced divers, Lochridge says "it wasn't just me" that refused to dive in the Titan sub.
Other divers "voiced their concerns," but they were "dismissed" by OceanGate CEO Stockton Rush and engineering director Tony Nissen,
From the "get go," Lochridge says Nissen "gave me zero confidence" in the sub, despite it being "under my care".
"Hands down I would never go in that thing," he says, adding he would not have "encouraged" anyone to go in, including his trainees.
"I knew [Rush] was going to let me go for the way I was being anti-project at that point," saying it was "unfortunate" his concerns were ignored.
Lochridge looks back at his 25 years of experience and says that "as a diver it is your right to demand to get information on areas where you are putting yourself at risk" in order to "to mitigate the potential for disaster."
He tells the hearing that he formally brought every issue to senior management, but the company's health and safety policies were "highly inaccurate".
After a short break, the hearing starts again with the focus turning to OceanGate's health and safety manual.
David Lochridge says this manual was in place before he came to the company.
The hearing is shown the document and the following sentence - written by OceanGate CEO Stockton Rush - is printed all in capital letters: "No job is so important that we cannot take the time to do it safely."
"That wasn't the case", Lochridge says.
He says he wants to go on record to state that the manual refers to an "open door policy" about any issues and how the company would provided a safe environment, but this was "so incorrect it was untrue."
David Lochridge, OceanGate's former director of marine operations, is continuing to give evidence to the hearing.
Here is a map out the Titan's route and descent to the wreckage site of the Titanic, supplied by the US Coast Guard.
This animation has been shown in the hearing.
Titan sub: Animation shows how vessel made descent to Titanic wreckage
Lochridge says given all the problems he found in the sub, "there was no way I was signing off" the submersible.
He also mentions that apart from his involvement in the Titan, he was carrying out other duties such as maintenance and daily operations.
At the same time, his team "was getting thinner and thinner," as the turnover rate was "incredible," he tells the hearing.
The hearing is now shown pictures of an oxygen and scrubber unit, a technical part of the Titan sub.
"Stockton liked to do things on the cheap," Lochridge says of the former chief executive of OceanGate.
He says what is pictured is "Stockton's idea" of a scrubber unit.
The scrubber maintains the atmospheric pressure in the sub, Lochridge says, so it's an important part.
He goes on to explains that Stockton decided not to use a known manufacturer such as James Fisher Defence who are known for "properly built" scrubbers.
Rebecca Morelle
Science editor
Usually the pressure hull of a sub - the part where the passengers sit - is made from metals like titanium, which is extremely reliable under pressure.
But Titan’s hull was made from carbon fibre.
Basically the carbon fibre was mixed with resin and built up into layers until it was 5in (13cm) thick.
But David Lochridge has just told the hearing about his worries about the quality of the material.
He’s just shown a picture where you can see the layers coming apart - a process called delamination.
And in another image, he has shone a torch through the sample of the hull’s material - you can see the light pouring through.
He said the material was not good to start with - but the problem is that more damage is caused by a dive to the deep. It becomes weaker with every descent.
On the left, the picture shows layers of carbon fibre coming part - known as delamination, and on the right, a light is shone through the material the hull was made from.
Lochridge continues to detail his concerns over the submersible - how he must have "100% confidence" in piloting them and bringing people up safely.
You must be able to do this without worrying that components are "going to fail," he tells the hearing.
"If you don't have the confidence in it, you don't do it. That's it."
Lochridge says he was very vocal about the safety of the sub, telling "every director within the organisation".
"It didn't help the relationship, but at the end of the day, safety comes first," he adds, as that is more important than "making money".
Going in a submersible is a risk, Lochridge says, but "don't take risks that are unnecessary," adding that many people were aware of the "faulty" and "deficient" equipment being used.
Rebecca Morelle
Science editor
This is the first time David Lochridge has spoken publicly about his time at OceanGate.
Until now we’ve only had access to court documents that revealed his concerns about the sub’s safety.
This is a man who is extremely experienced in deep sea operations - through his time at the Royal Navy and afterwards working on commercial subs.
It feels like he has a lot to get off his chest - particularly about his relationship with Stockton Rush.
Lochridge’s detailed description of a dive to a wreck on another sub with Rush was jaw dropping.
There were tussles over who was piloting the craft - which Stockton Rush won, tales of reckless manoeuvres, including a 180 degree turn at full speed that resulted in the craft getting jammed amongst the wreck.
Finally we were told that Rush threw the controls at Lochridge’s head.
We are now hearing about his concerns, we know that the consequence of raising these resulted in him being fired.
Lochridge tells the hearing that his duty is to the passengers and to himself, ensuring confidence in the equipment for the journey.
Asked if he trusted how the Titan was built, Lochridge replies, “No confidence whatsoever.”
Lochridge had raised concerns with OceanGate and says he believes the company dismissed them due to cost-cutting, poor engineering decisions, and “the desire to get to the Titanic as quickly as they could, to start making profit.”
Lochridge says his relationship with the company had "broken down" in 2016.
He "maybe came across as the troublemaker" because he was "so outspoken" on "many issues", he adds.
Lochridge also says he thinks a lot of his previous team left "because they weren't happy with the conditions," and how senior management treated them.
He adds that he wasn't involved in the winding of the first Titan hull, and he was not asked to be a part of that process.