Wow, this is another incredible 3D printing achievement. Startasys' RedEye has partnered with Lockheed Martin to 3D print what may be one of the largest FDM based prints ever. They have printed out 2 large satellite fuel tank simulators. The simulators will be used in testing prior to constructing the actual tanks for the satellites. By 3D printing these prototypes Lockheed Martin has saved about half of the costs they would have encountered by machining the parks.
http://3dprint.com/2988/lockheed-mar...nt-fuel-tanks/

The larger of the 2 fuel tank simulators measures an amazing 15 feet in length. It took about 2 weeks in total to print out both tanks. That may seem like a long time, however it actually saved the company a great deal of time over traditional manufacturing methods. Check out these huge tanks which were 3D printed in 10 and 6 pieces each: