Members of NASA’s Office of Safety and Mission Assurance Nondestructive Evaluation (NDE) Working Group, along with the American Society for Testing and Materials (ASTM), collaborated in the development of voluntary consensus standards for NDE of flat-panel polymer matrix composites as well as thin-walled metallic liners and overwraps in composite overwrapped pressure vessels. Before this effort, there were no comprehensive standards for NDE in these areas.

“A gap was identified that we scarcely had any standards for NDE of composites and more were needed,” stated Dr. Jess Waller, material scientist at NASA’s White Sands Test Facility with Jacobs Technology Inc.

Two standards — a Guide for Nondestructive Testing of the Composite Overwraps in Filament Wound Pressure Vessels Used in Aerospace Applications (ASTM E2981) and Guide for Nondestructive Testing of Thin-Walled Metallic Liners in Filament-Wound Pressure Vessels Used in Aerospace Applications (ASTM E2982) — were recently approved and formally adopted by ASTM.

These standards are the latest in a long list of NDE standards on composites produced by the ASTM subcommittee E07.10 Task Group on Nondestructive Testing of Aerospace Materials.

“The effort is NASA-led,” explained Waller. “We’re interfacing with United States industry and commerce and developing standards for NDE of composite materials and hybrid composite structures.”

Other standards include

• Standard Guide for Nondestructive Testing of Polymeric Matrix Composites Used in Aerospace Applications (ASTM E2533)
• Standard Practice for Ultrasonic Testing of Flat Panel Composites and Sandwich Core Materials Used in Aerospace Applications (ASTM E2580)
• Standard Practice for Shearography of Polymer Matrix Composites and Sandwich Core Materials in Aerospace Applications (ASTM E2581)
• Standard Practice for Infrared Flash Thermography of Composite Panels and Repair Patches Used in Aerospace Applications (ASTM E2582)
• Standard Practice for Acoustic Emission Examination of Plate-Like and Flat Panel Composite Structures Used in Aerospace Applications (ASTM E2661)
• Standard Practice for Radiologic Examination of Flat Panel Composites and Sandwich Core Materials Used in Aerospace Applications (ASTM E2662)

The above standards capture modern inspection practices and supersede AIA/NAS NAS999. They currently are being used by various aerospace organizations, and are available to NASA employees and support contractors through the NASA Technical Standards Program.