I spent about seven years during the Vietnam War flight-testing airplanes for the Air Force. And then I went in and I had a lot of fun building airplanes that people could build in their garages. And some 3,000 of those are flying. Of course, one of them is around-the-world Voyager.

When theres ever a breakthrough, a true breakthrough, you can go back and find a time period when the consensus was 'well, thats nonsense!', so what that means is that a true creative researcher has to have confidence in nonsense.

To allow public access to orbit, we would need breakthroughs that would lower the cost by a lot more than an order of magnitude and increase safety by a factor of 100 as compared to every launch system used since the first manned space flight. I think airborne launch will be a significant part of the safety solution.

Achieving something that has never existed in manned spaceflight and that is high volume and public access.

In the coming era of manned space exploration by the private sector, market forces will spur development and yield new, low-cost space technologies. If the history of private aviation is any guide, private development efforts will be safer, too.

The next 15 years will see thousands of people leave the atmosphere on suborbital flights. My company's SS2 system might fly 100,000 people by 2024. If it is shown to be highly profitable, perhaps we will see 20,000 people traveling to orbit by 2035, and then thousands to the moon by 2050. If we make a courageous decision, like the program we kicked off for Apollo, we will see our grandchildren in outposts on other planets.

Testing leads to failure, and failure leads to understanding