The space shuttle crew receives special training on how to repair potentially dangerous surface cracks in the Reinforced Carbon-Carbon (RCC) on the wings or nose cap during flight. Before this safety procedure could be fully implemented, the crack sealer had to undergo extensive testing and modeling to accurately predict its behavior in a high temperature environment.

This small crack repair project is called Non-Oxide Adhesive eXperimental (NOAX). It was led by engineers at Johnson Space Center in conjunction with NASA Glenn Research Center’s Materials and Structures Division, Marshall Space Flight Center, Langley Research Center, ATK and Materials Research & Design Inc.
The NOAX team was tasked with investigating the crack repair material and developing a model for its behavior on re-entry into Earth’s atmosphere. Glenn’s role was to provide kinetic data on its oxidation/vaporization behavior during re-entry.

To accurately build these mathematical models, the team at Glenn performed a series of controlled, high temperature tests to measure the rates of reaction of this material with hot oxidizing gases in a laboratory furnace. The results of these tests coupled with microstructural examinations before and after exposure provided the needed data to the team members developing the model.

In addition, these tests were correlated to the arc-jet tests at LaRC and JSC, which more accurately simulate the re-entry environment. The fully tested material will further ensure the safety of the shuttle crew in case an emergency repair is required.