This is an enthusiastic statement from their team after this successful test:

“Additive manufacturing opens up new possibilities for our designers and engineers,” said Pat Nolan, Vice President and General Manager of Orbital ATK’s Missile Products division of the Defense Systems Group, in a statement. “This combustor is a great example of a component that was impossible to build just a few years ago. This successful test will encourage our engineers to continue to explore new designs and use these innovative tools to lower costs and decrease manufacturing time.”

Where do you think the first mission with a 3D printed part will go?

thanks to iflscience.com for the great info

thanks to NASA for the pic