James Cameron concedes Jack 'might have lived' after testing Titanic door theory

James Cameron has admitted Leonardo DiCaprio's character Jack "might" have survived following a new investigation into the Titanic door debate.

Ever since the blockbuster was released in 1997, fans have questioned whether Jack would have been able to survive the freezing waters if he held onto the broken door alongside Kate Winslet's Rose during the emotional final sequence.

But after conducting a "forensic investigation" into the fan theory as part of the National Geographic special, Titanic: 25 Years Later, Cameron confessed that there was a small chance Jack would have lived if he and Rose placed their bodies high on top of the door and had only their lower legs in the water.

"Final verdict: Jack might have lived but there's a lot of variables," he said of the results, according to a preview obtained by Rolling Stone. "In a well-lit experiment in a test pool, we can't possibly simulate the terror, the adrenaline, all the things that would have worked against them. (Jack) didn't get to run a bunch of different experiments to see what worked the best. Jack's survival might have come at the cost of her life. Based on what I know today, I would have made the raft smaller so there's no doubt."

For the experiment, Cameron and his team employed stuntpeople to act out four different scenarios.

In one test, the filmmaker noted that Jack would have most likely suffered hypothermia and died within 20 minutes, while in another, which saw Jack and Rose lift just their torsos onto the raft, they ruled they would both freeze to death.

Titanic: 25 Years Later will be released on 5 February.