Mission specialist Renata Rojas told a US Coast Guard panel investigating the disaster she was "learning a lot and working with amazing people" at OceanGate, the underwater tourism company.

British adventurer Hamish Harding and father and son Shahzada and Suleman Dawood died alongside OceanGate Expeditions' chief executive Stockton Rush and Frenchman Paul-Henri Nargeolet when the Titan submersible imploded en route to the wreck site in June 2023.

Ms Rojas called some of her colleagues "very hard-working individuals that were just trying to make dreams come true".

She admitted she knew the mission was "very risky" but said she "never at any point felt unsafe".

Ms Rojas was emotional at times during her evidence on Thursday and at one point the panel suggested a brief break so she could collect herself.

Video footage of the submersible on the ocean floor was also published on Thursday.

Ms Rojas's comments contrasted sharply with previous evidence, in which Mr Rush, the CEO, was described as volatile and quick to temper by other staff.

On Wednesday, former operations director David Lochridge called the vessel "an abomination" and said the company was committed only to making money.

Along with other witnesses, Mr Lochridge painted a picture of a company led by people who were impatient to get the unconventionally designed craft into the water.

It was noted at the start of the hearing that the submersible had not been independently reviewed, as is standard practice.

During the Titan's final dive on 18 June 2023, the crew lost contact with its support ship after an exchange of texts about the Titan's depth and weight as it descended.

One of the last messages from Titan's crew to the Polar Prince before the submersible imploded said "all good here", according to a visual recreation presented earlier in the hearing.

Read more from Sky News:
The stories of the Titan submersible crew
What happened to the Titan?

When the submersible was reported missing, rescuers rushed ships, planes, and other equipment to an area about 435 miles south of St John's, Newfoundland.

Four days later, the wreckage of the Titan was found on the ocean floor about 300 metres off the bow of the Titanic, Coast Guard officials said.

Nobody on board survived.

The Titan had been making voyages to the Titanic wreckage site going back to 2021.

The hearing is expected to run through to Friday with more witnesses still to come and resume next week.