Nearly a century after the Titanic plunged into the murk of the Atlantic Ocean, a new secret has been revealed that could upend the existing story of how the ship sank.
Until now, historians believed that Titanic rammed an iceberg because it was steaming too fast and the crew didn't see it until it was too late.
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According to Louise Patten, the granddaughter of the only senior officer to survive the wreck, Charles Lightoller, Titanic hit the berg because the man at the wheel made a mistake, misunderstanding an order and turning right instead of left.
Though the helmsman corrected the error shortly thereafter, the supposedly unsinkable ship was already on a collision course with the iceberg that would rip into her hull, taking the lives of some 1,500 people.
"Turning the wheel the wrong way was a blunder," Patten said. "She'd gone half a mile nearer the iceberg and it was just too close to avoid it."
Could the helmsman really have made that mistake? And if so, could it have stayed secret for so long?
"I think it's entirely possible," James Delgado, the president of the Institute of Nautical Archaeology at Texas A&M, told ABC News.
After impact, Patten said, the chairman of the White Star Line gave the order to sail on to port, hoping to avoid a PR crisis.
"She took on far more water than she would otherwise have done," Patten said. "She only survived another two hours."
Some experts disagree, saying that even if an order to sail on was given it wouldn't have made any difference.
"The water was going to come in regardless," Delgado said.
According to Patten, the true story of the Titanic disaster has remained a family secret for decades. She claimed her grandfather lied about the events because admitting human error would have brought lawsuits, the end of the White Star Line and the end of his job.
Now, Patten is making the details of her family secret public in a new book, "Good as Gold."
"After 98 years, everyone who could be hurt by my writing this is dead," Patten said. "And I thought it is probably right that the world now knows what actually happened on Titanic."
It is just the word of one dead man. But if it's true, it could be tragic to think that, but for a misunderstood order, the fateful voyage could have ended very differently.