The Orion capsule's heat shield survived its test flight back in December just fine. In fact, Orion Program Manager Mark Kirasich says it "met every expectation" during reentry, enduring temperatures that reached 4,000 degrees Fahrenheit. Thanks to the data NASA gathered from the same test, though, its engineers were able to come to the conclusion that the heat shield used for that flight won't make it through Orion's first mission with the Space Launch System scheduled to happen in 2018. The multi-purpose vehicle will travel farther during the Exploration Mission 1 three years from now. As such, it's bound to encounter colder temperatures and to travel faster -- and hence, face even worse heat -- upon reentry.
The engineers' answer to the problem is to redesign the fiberglass honeycomb layer placed on top of the heat shield's titanium/carbon fiber body to make it even stronger. That covering (comprised of 320,000 cells) is meant to disintegrate upon reentry, but it should still be tough enough to protect the capsule and its future passengers on their way home from deep space missions. The good news is that the heat shield isn't one solid structure, and different parts can be manufactured in different places at once. This method won't only save NASA some precious, precious money, but will also shorten the heat shield's manufacturing process by two months.
[Image credit: Lockheed Martin]