The Aging Aircraft and Durability (AAD) Project is part of the NASA Aviation Safety Program.
The goal of the AAD Project is to perform foundational research in aging science that will ultimately enable system-level integrated methods for the detection, prediction and mitigation/management of
aging-related hazards for future civilian and military aircraft.
The Project is organized relative to these three theme areas:
Detect locate and characterize fully damage or degradation of materials and structures Predict life and strength predictions accounting for accumulated damage associated with long-term exposure to thermal/mechanical/environmental loads Mitigate concepts to prevent, contain, or manage degradation associated with aging B-4 The focus of AAD is on aging and damage processes in new aircraft designs and 'young' aircraft, rather than life extension of legacy vehicles.
There is an emphasis on new and emerging material systems/fabrication techniques and the potential hazards associated with aging-related degradation.
The scope and technical content for the AAD Project was developed to accomplish two objectives:
(1) deliver technology to address specific end-user problems and (2) develop fundamental technology (not isolated to a single application) to enable integrated tools.
The first objective was addressed by establishing a set of Challenge Problems (CP) to define representative physical problems to be addressed by the project.
Challenge Problems have been defined for eight application problems:
Damage Methodology for Metallic Airframe Structures CP-02:
Structural Integrity of Integral Metallic Structure CP-03:
Durability and Structural Integrity of Composite Skin-Stringer Fuselage Structure CP-04:
Durable Bonded Joints CP-05:
Durability of Engine Fan Containment Structure CP-06:
Durability of Engine Superalloy Disks CP-07:
Durability of Engine Hot Section CP-08:
Wiring Degradation and Faults To accomplish the second objective, fundamental technology development not isolated to a single application, AAD has defined a four-level approach to technology development and integration, and will conduct research across each of these levels to address evolving safety challenges.
At Level 1, foundational research will be conducted to further the fundamental understanding of the underlying physics and develop an ability to model that physics in:
sensing and diagnostic technologies; physics-based modeling; continuumbased models and computational methods; material science (metals, ceramics, composites); and characterization/validation test techniques.
At Level 2, the foundational research produces technologies and analytical tools focused on discipline-based solutions to leverage the development of NDE Systems; Structural Integrity tools; Lifing methods; and Mitigation concepts.
At Level 3, methods and technologies are developed to balance solutions across disciplines.
The Detect capability is enhanced by coupling NDE and structural integrity analysis, the Predict capability is enhanced by applying NDE to improve model input and provide improved remaining life and strength predictions, and the Mitigate capability is enhanced by applying predictive models to develop advanced mitigation concepts.
At Level 4, results from Levels 1 through 3 activities are built upon to integrate Detect, Predict, and Mitigate capabilities for system-level performance, and system-level experiments are conducted for validation.
A summary of the Projects technical plan is available at:
http://www.aeronautics.nasa.gov/programs_avsp.htm NASA will focus its core competencies and resources on NASA-appropriate research areas at all levels, and with partners, on the levels that are appropriate to each partner.
The AAD Project will work with partners from other government agencies, industry, and universities to fills the gaps that NASA research cannot address.
This solicitation is intended to fill such gaps at Level 1 and Level 4. The proposed research efforts are an B-5 integral component of the overall project content and have been defined to contribute to specific Challenge Problem and Theme-based technology needs.