A key component in a structural health monitoring system for aircraft applications is nondestructive inspection (NDI) data. Much of the data generated by advanced NDI systems is in the form of 2- and 3-D data sets that utilize proprietary data formats developed by manufacturers of those systems. Having that data in a neutral data format allows data sharing and evaluation using non-legacy data analysis, processing and archival software.
NDI Data Management IssuesIn certain high-value components on aircraft structures where damage-tolerant analysis is employed, certain in-service defects may be permitted. For example, in metal structures where corrosion in wing skins and planks or cracking in wing spars are detected, those areas are treated and arrested to halt further propagation. As long as the corrosion or crack size is within allowable limits, that component may return to service.
With the increased use of composite materials in aircraft structures, the most common in-service defects encountered include impact damage, cracks and delaminations. These defects may or may not be easily repaired, depending on the size of the component and location of the indications. These areas may require continuous monitoring for the life of the component.
These cases are but two examples of where NDI data records may need to be maintained and archived for the life of the aircraft. Several issues come to mind:
What is required is a common data format for the exchange, analysis and archiving of NDI image data that is independent of proprietary vendor formats, adaptable to large amounts of data and NDI method independent. DICONDE is one such format.
It is an evolving American Society for Testing and Materials (ASTM) standard that provides a way for nondestructive evaluation (NDE) manufacturers and users to share image data. Implementation of the DICONDE format enhances those aircraft structural health monitoring systems.
The Solution: DICONDEDICONDE is a data standard adopted by the ASTM that provides a format for nondestructive evaluation manufacturers and their customers to share image data. It is based on the American College of Radiology (ACR)/National Electrical Manufacturers Association (NEMA) standard, DICOM (Digital Imaging and Communications in Medicine). The DICONDE standard encompasses all NDE-specific imaging methods and technologies, such as digital radiography, ultrasonics, eddy current, visual and computed tomography.
DICONDE is an extension of the DICOM international standard and benefits from its years of development. The ASTM standard, ASTM E-2339 “Standard Practice for Digital Imaging and Communication in Nondestructive Evaluation,” was established in 2004. According to ASTM, DICONDE is:
Benefits with DICONDECompliancy with the DICONDE data standards offers several significant benefits, including:
Usage of a DICONDE data standard enables the exchange, analysis and archiving of NDI image data that is independent of proprietary formats. It is adaptable for handling large quantities of data, as well as being independent of the NDI method.
A wide range of DICONDE-compliant software is available on the market with a wide range of features and costs. Some are good if operators are just getting started with DICONDE and want to learn their way around, while others are full-featured inspection management software systems.
The DICONDE specifications are very similar to the DICOM specifications, the main modifications being those to replace “patient” details with those for “components” details. A number of private attributes also have been added for elements not supported by existing official DICOM attributes. In some cases, software solutions designed around the DICOM standard will work with DICONDE data.
The maintenance, distribution and archival of NDI data is one of the major components in an aircraft structural health monitoring system. The data generated by today’s advanced NDI systems create large data sets usually in proprietary data formats. This data cannot be easily shared and analyzed across a network, nor archived and retrieved for later data comparison over the life of an aircraft.
With today’s new breed of inspection management software, there is a stable platform to manage the entire NDI process for an entire aircraft fleet. And that platform standard is DICONDE.