What is a space plane and how does it work? From the Space Shuttle to the super secret X-37B, we look at the designs and proposals for reusable spacecraft.Learn more about advertising on the HowStuffWorks podcasts at www.howstuffworks.com/advertisers.htmAnd to learn about your ad choices when listening to podcasts, visit https://www.howstuffworks.com/privacy.htm#ad-choices
