'I won't be going to his funeral': Branson's wife

It's Virgin Galactic's fourth crewed mission, but this test flight will be the first flight to carry a full crew including Branson, two pilots and three other specialists.

The flight will take him to the edge of earth's atmosphere, where he will experience a few minutes of weightlessness.

Asked how his family reacted to the news that he would be on the flight, Branson said his children are adventurous, but it's clear they get that quality from him.

"As a family, our motto is, 'The brave men don't live forever but the cautious do not live at all.' And so, as a family, we love to say 'Yes.' My wife is the sort of person who would be terrified on a Virgin Atlantic airplane or a Virgin Atlantic plane. She's the last person who would want to do something like this. But she's known me since I tried to balloon across the Atlantic or the Pacific or around the world, and she still seems to love us."

Branson said his wife Joan, to whom he has been married since 1989, is supportive but practical about his incredible sense of adventure.

"I won't be going to his funeral.' That's the kind of lady she is: 'If you're foolish enough to do these wonderful things, you can do it, but I (referring to wife Joan) won't be going to your funeral," he said, laughing.