(redistributed by permission from Dennis Roach, Sandia National Labs)
The Sandia National Labs’ FAA Airworthiness Assurance NDI Validation Center (AANC), in association with the Federal Aviation Administration, is conducting a survey to identify and prioritize research and development needs associated with implementing Structural Health Monitoring (SHM) on aircraft. The Federal Aviation Administration is developing an SHM Research and Development Roadmap. In order for the roadmap to be accurate, it needs to contain the best possible inputs from aircraft manufacturers, regulators, operators, and research organizations so that all of the pertinent issues, ranging from design to deployment, performance and certification are appropriately considered. Towards that end, this survey is being sent to persons involved with the operation, maintenance, inspection, design, construction, life extension, and regulation of aircraft.
The survey will only take a few minutes of your time to complete, so please consider providing your essential input. All input is anonymous and cannot be traced to the survey respondent.
Thank you for your time and for providing your valuable feedback. We appreciate your response!
Overview of SHM Survey
This survey is being sent to aircraft manufacturers, regulators, operators, maintenance depots, technology developers, and other appropriate research groups. It is not expected that each recipient will be able to address the full set of questions. Please answer the questions that are appropriate for your area of work. Additional comments beyond the multiple choice responses are welcomed. In return for your participation in this survey, you have the option of being included on the distribution of the survey results. In order to take advantage of this option, you will need to include your e-mail address where requested in the survey. Your name and contact information will be kept confidential and will not be traceable to the answers you provide in the survey.
Your timely consideration of this request will be greatly appreciated. Your cooperation is requested in completing the survey online. Thank you for your interest and agreement to participate in this survey.
FAA Airworthiness Assurance Center
Sandia National Labs
Motivation for SHM Survey
The Sandia National Labs’ FAA Airworthiness Assurance NDI Validation Center (AANC), under contract to the Federal Aviation Administration’s William J. Hughes Technical Center, is collecting information through this survey to identify and prioritize research and development needs associated with implementing Structural Health Monitoring (SHM) on aircraft. Specific emphasis is placed on structural and maintenance characteristics that may impact the operational performance of an inspection process or health monitoring system. We plan to share the summary of results with all interested respondents. You can also be placed on the distribution list for reports, procedures, etc. stemming from this program.
The AANC works closely with industry to make sure its products will have the maximum impact on improved safety and reliability. Your timely consideration of this request will be greatly appreciated. Your cooperation is requested in filling out the survey using the Web site supplied.
The use of in-situ sensors for real-time health monitoring of aircraft structures can be a viable option to overcome inspection impediments stemming from accessibility limitations, complex geometries, and the location and depth of hidden damage. A general, basic description of SHM is:
Structural Health Monitoring (SHM) is the use of in-situ, mounted or embedded sensors and analysis to aid in the assessment of structural or mechanical condition or system operation including the direct detection of structural flaws. Parameters to be monitored could indicate flaws directly or could be physical properties such as load, strain, pressure, vibration, or temperature from which damage, malfunction, mechanical problems, or the need for additional investigation can be inferred.
A more detailed description includes:
Structural Health Monitoring (SHM) – sometimes referred to as “Smart Structures” or “Smart Systems;” involves the use of nondestructive inspection principles coupled with in-situ sensing to allow for rapid, remote, and real-time condition assessments. The sensors may record certain signatures wherein deviations from such signatures may indicate a mechanical issue which needs to be addressed. Alternately, the sensors may deterministically detect a flaw thus indicating the type of damage and location for further assessment. Such a system may be used to conduct nondestructive inspections for areas of the aircraft which have been traditionally difficult to access. SHM systems my either be used to supplement normally scheduled inspections, or provide continued monitoring of a given structure. The goal is to reduce operational costs and increase lifetime of structures by providing:
• Greater vigilance in key areas
• Overcome accessibility limitations, complex geometries, depth of hidden damage
• Eliminate costly & potentially damaging disassembly
• Minimize human factors using automated data analysis
Currently, there are no industry standard guidelines, FAA guidance, or agreed-upon procedures for assessing the performance of SHM systems and safely integrating their use into routine aircraft maintenance. The introduction of SHM systems into routine aircraft maintenance practices is projected to become more widespread in the coming years. Thus, there is a significant need for the FAA to be current with the systems being proposed in order to provide any needed regulatory guidance to allow timely implementation of these technologies. The Federal Aviation Administration is addressing these issues through the development of an SHM Research and Development Roadmap. In order for the roadmap to be accurate, it needs to contain the best possible inputs from aircraft manufacturers, regulators, operators, and research organizations so that all of the pertinent issues, ranging from design to deployment, performance and certification are appropriately considered.
The SHM Roadmap will provide information and guidance that will support the safe adoption of SHM practices and allow the aviation industry to make informed decisions about the proper utilization of SHM. It will be used to assess what regulatory guidance is needed to assure the safe incorporation of SHM through formal certification programs. The FAA SHM R&D Roadmap will be produced through coordination with SHM activities worldwide so that it adequately reflects the status of SHM technology and helps identify regulatory issues facing the aviation industry in adopting SHM practices. Ultimately we anticipate that this SHM R&D Roadmap will define what the FAA needs to enable the insertion of SHM in commercial transport airplanes for current and future applications including fatigue monitoring, corrosion and wear assessments, and accidental impact damage.
An important element in developing the FAA SHM R&D Roadmap is a clear understanding of the current status of SHM technology and the pending regulatory issues facing the aviation industry to safely adopt SHM practices. Towards that end, this survey is being used to solicit your input.
The objective of his effort is to produce a ten-year FAA SHM Research and Development (R&D) Roadmap for transport commercial airplanes that will address the following items:
• Guidelines for SHM designers and engineers. Agreed-upon procedures for assessing the performance of SHM systems. Agreed-upon procedures for certifying SHM systems
• List of impediments and challenges associated with deploying SHM solutions
• Information and guidance that will support the safe adoption of SHM practices and also allow OEMs, regulators, and carriers to make informed decisions about the proper utilization of SHM
• Identification of R&D tasks needed to enable the FAA to assess SHM technologies for compliance with certification and continued airworthiness requirements
• Necessary data to allow the FAA to evaluate any changes to maintenance and design practices by operators and manufacturers seeking economic and technical performance benefits for implementation of SHM.
The SHM R&D Roadmap will be used by the FAA to assess the state of SHM and define regulatory needs associated with: 1) developing SHM certification and continued airworthiness requirements, 2) developing regulatory guidelines and advisory materials for the implementation of SHM, 3) allowing the FAA to evaluate changes to maintenance practices stemming from implementing a SHM, 4) setting guidelines for assessing the reliability and maintainability of SHM.