National Aeronautics and Space Administration

Glenn Research Center

Ballistics Impact Facility

July 18, 2012

On Wednesday, July 18, the Space Academy toured the Ballistic Impact Laboratory at Glenn. On this fascinating tour, we learned that the facility was built after the Columbia tragedy in 2003. The Columbia failed due to a piece of foam that damaged the heat shielding system. The Ballistic Impact Laboratory exists to enable research in ways to help prevent similar tragedies from happening and to improve the design of several aerospace components.

The tour guide led us in to a first room with a large gas gun which could perform 4-5 impacts a day. Turbine engines are often impacted by foreign objects, such as birds, during flight. When the birds hit the turbine fans, serious malfunctions can occur. The facility tests materials that are used on engine fans against several impacts. The projectiles’ dynamics and the impacts they make on the target materials are analyzed and recorded. The purpose of the tests is to help develop better, lighter, and stronger materials and systems that can perform well during use (in this case, specifically turbine fans). Characteristics such as strain, deformation, and stresses are evaluated under the loadings presented to the materials. On the walls of the room we saw several bits of brown particles. The tour guide told us that the brown pieces are actually gelatin that is used to simulate birds hitting the engines. Back in the main room, he showed us to a refrigerator that contained very old logs of the gelatin. The disturbing brown log was 4 pounds, jiggly, and moldy to represent a bird. Everyone got to examine the “bird”.

We visited the next room where a vacuum gun tested smaller samples of wheat. We were shown several “aftermath” samples which had taken on interesting shapes after testing. The gun could reach speeds of up to 3000 feet per second. The tour guide showed us several videos of impacts that were tested in the facility. The slowed-down videos showed the impact characteristics of both the projectile and the material being hit. Small dots were on some of the samples. The dots are used to digitally find characteristics such as strain.

Finite element analysis was performed on a sample in one of the videos. The analysis was able to accurately show the crash characteristics of the material, including exactly where a fracture took place and how devastating the fracture was. We learned that altitude conditions are simulated using different temperatures and pressures. The tour ended with Gina walking away with her very own oddly shaped impact specimen.