Stockton Rush desired to be remembered as an inventor. It didn’t seem to matter how he went about it.

His aim was to be the first person to reach Mars. He was bright, determined, and born into riches.

He switched his attention to the water when he realized that was unlikely to happen in his lifetime.

“I wanted to be Captain Kirk, and in our lifetime, the final frontier is the ocean,” he told a reporter in 2017.

The sea had the promise of adventure, adrenaline, and mystery. He also believed it offered rewards if the submersible he helped develop, which he commanded his business OceanGate to build, was a success.

He had a daring personality that drew people in, winning him the respect of his employees, passengers, and investors.

“His passion was amazing, and I bought into it,” said Aaron Newman, who traveled aboard Mr Rush’s Titan sub and later became an OceanGate investor.

However, Mr Rush’s lofty ambition sparked criticism from industry experts, who cautioned that he was cutting shortcuts, putting innovation ahead of safety, and risking possibly disastrous effects.

It was something he was not willing to accept.

He and four other passengers on board the Titan were killed when it imploded last week.

“You’re remembered for the rules you break,” Mr Rush once observed, paraphrasing US General Douglas MacArthur.

“I’ve broken some rules,” he admitted, referring to the Titan. “I think I’ve broken them with logic and good engineering behind me.”

Stockton Rush III was born in 1962 in California to a family who built a fortune from oil and shipping.

He was transferred to the prestigious boarding school Phillips Exeter Academy in New Hampshire, where he earned a bachelor’s degree in aerospace engineering in 1984.

At the age of 19, he became the world’s youngest pilot to qualify for a jet transport rating, the highest pilot certification available. He worked on F-15s and anti-satellite missile programs in the hopes of someday joining NASA and becoming an astronaut.

However, when a trip to Mars became increasingly out of reach, that ambition began to fade.

“If you tell me what the commercial or military reason for going to Mars is, I believe it will happen,” Rush told Fast Company magazine. “It’s all just a dream.”

So he moved his focus lower and, in 2009, launched OceanGate, a private company that provided consumers – Mr Rush preferred the term “adventurers” – with the opportunity to experience deep sea travel, including a visit to the Titanic wreck.

The company was small and close-knit, situated in Everett, Washington. Rush would preside over all-staff meetings at the company’s headquarters, while his wife Wendy – another 1984 Princeton graduate – served as his director of communications.

A junior employee who worked at OceanGate from 2017 to 2018, who requested anonymity, described the firm headquarters as “homey and lived-in,” with wiring and equipment apparently everywhere. “It was very free-flowing.”

Mr Rush was in command.

“He was just really passionate about what he was doing and very good at instilling that passion into everybody else that worked there,” said one colleague to the BBC.

Mr Rush brought virtual reality goggles to a staff meeting and invited everyone to enjoy a virtual underwater tour. Mr Rush told them that this was their goal: to allow more people to hold this viewpoint. “This is the world I want,” he said.

According to Mr Newman, the investor, Mr Rush was “not a leader from the back, telling people what to do – he led from the front.”

Mr. Newman went aboard the Titan with Mr. Rush to see the Titanic wreck in the summer of 2021.

Mr Rush “spent hours” talking with him about the possibility of investigating the ocean’s bottom the first time they met.

Mr Rush “took his own path,” according to Mr Newman.

Mr. Newman remembered OceanGate as a team that looked out for one another.

And, according to Mr Rush, his wife, Wendy, was “up at the top, looking over his shoulder, making sure he was doing everything perfectly and not cutting corners or skipping things.”

Mr Rush captivated Mr Newman to the point that he chose to invest in OceanGate. “You know, I wasn’t sure whether I’d ever see any return. “That wasn’t the point,” he explained.

“The point was to be a part of something experimental that’s breaking new ground, pushing forward our technology, and how the world works, and going places and doing amazing things, that’s what this is about.”

Mr. Newman identified himself as a small investor. OceanGate, as a private firm, is not required to publish full financial documents. According to US bank records from January 2020, Mr Rush and his other directors sold a $18 million interest in the company, which is assumed to have been used to fund Titan development.

To recuperate the costs, OceanGate’s sub, described as “well-lit and comfortable,” was priced at $250,000 (£195,600) for an underwater voyage.