Community Research and Development Information Service - CORDIS

FP7

WISDOM Report Summary

Project reference: 325978
Funded under: FP7-JTI

Periodic Report Summary 3 - WISDOM (WING STRUCTURAL TEST DEVELOPMENT METHOD)

Project Context and Objectives:
WISDOM main objective is to approach an innovative and reliable solution for the design, manufacturing, set up and Commissioning and performance & analysis of the structural test of the port and starboard outer wing sections needed for flight tests of natural laminar flow on the SFWA flight test demonstrator under Clean Sky Program.
The main requirement for this wing structural part is based on their high dimensional stability and tight geometrical tolerances to compliance with surface quality for a natural laminar flow condition, and therefore stability control and manufacturing precision over the test bench tools to be designed and manufactured shall consider this, avoiding as much as possible interfaces with the specimen upper surface.

The test procedure is based in a Self-supporting test rig with flexible and adaptable plug and play loads introduction method with minimum specimen interface needs and wireless connection for data recording The main requirement for this wing structural part is based on their high dimensional stability and tight geometrical tolerances to compliance with surface quality for a natural laminar flow condition, and therefore stability control and manufacturing precision over the test bench tools to be designed and manufactured shall consider this, avoiding as much as possible interfaces with the specimen upper surface.
The test procedure is based in a test rig with flexible and adaptable plug and play loads introduction method with minimum specimen interface needs and wireless connection for data recording. The challenge of this project is to define the test method necessary to demonstrate that major components tests can be performed on flight test aircraft.

Currently wing bend test methods are destructive, incurring in high cost. The main goal of this proposal is to develop a NON-DESTRUCTIVE method for wing bend tests, innovating in minimum test bench-wing interfaces, Non destructive inspection methods (infrared thermography) and wireless data recording.

Project Results:
From the beginning of WISDOM Project, the Consortium members (SerTec, CTA and TEAMS) have been working with the idea to design and perform a Bending Up Test applying new concepts and leaning on new technologies available at the moment in order to reduce test time, achieve an environmental friendly test avoiding hydraulic applications, new specimen inspection methods, new way of connection, follow up test behavior and reception of the result of the test by the authorized people independently of their location and time, all of this without decreasing the security of the people involved when the test is running and safety of the specimen itself.
From design and stress engineering point of view, test tooling have been development and have passed several quality gates (CR and PDR) in accordance with Topic Manager and Airbus staff to ensure the rig tooling is suitable for carrying out the test, will not damage the specimen and accomplish with all the requirements for this project. Nowadays, tooling is almost ready to pass the CDR maturity level scheduled for 19 May´16.
During this period from the 2nd Reporting Period, the loads to be applied to the specimen has been changed, and the number of loads cases have been modified as well. The scope of the project has been reduced to only one wing (left wing).
Due to this loads modifications, the Stress Reports presented for the PDR have had to be updated and adapted to the new requirements. Each of the parts that comprise tooling have been re-calculated in order to study their stress level and designed in order to have a security factor of 2 minimum at the critical load case to prevent breakage of the tooling during test. All main assemblies have been calculated (BLADE whiffletrees, A340 wing attachment whiffletrees, Test slab connection structures, intermediate structures, crane interface structures,...) and the results showed in several stress documents uploaded in the web application FEM calculations documents deliverables.
As design work, several documentation has been issued for CDR quality Gate, such as:
• Assembly procedure manuals has been issued, describing the method and auxiliary tooling needed to build up all the elements the test rig. A chapter for secure and safety measure to protect the wing specimen during assembly phase has been added. These documents was required to pass the CDR and have been uploaded into the application.
• Test Campaign Description document for CDR, describing the test campaign proposed by the consortium, Test preparation and Test conduct. Due to the modification of the scope of the project, several changes has been made respecting of the one presented in at the PDR., such as reflect the reduced scope (one wing only), load cases modification from PDR to CDR, loads without 20% of margin applied in the PDR, new loads distribution on the winches not to damage A340 inner wing spars, modification of the total number of rosettes and strain gauges as per F57RE1507445 document,... This document was mandatory to pass the CDR.
Regarding the Specimen Instrumentation Drawings, TEAMS has delivered a first set of drawings with the location of the strain gauges and rosettes to be installed prior the Test and ergonomic studies in order to decided which instrumentation must be installed before closing the Wing Torsion Box and which of them could be installed later on.

For new technologies expected to be applied during Wing Bending Up Test, the core of the R&D work packages of the WISDOM project, the main quality gate, Critical Technological Review (CTR) has been held at SerTec premises with Topic Manager and members of the Consortium in charge of these new technologies in order to check the status and maturity of each of them and validate their application into the BLADE program

The main new technologies reviewed at CTR were:
- New Load Introduction Systems: The proposed method is to use electrical devices based on winches. This method is very convenient when used in only pulling tests. The High Precision Servo-controlled Winches (HPSW) will be capable of controlling the load by using Brushless Motors for winches actuation while using appropriate motor driver for controlling. The servo-loop will be closed externally using the typical Test Controllers as those provided by the well known brands as MTS o FCS/MOOG. Consequently there are two closed loops one internal to the motor driver and one external as described previously. This system is clean, because it use electrical power instead of hydraulics, and the power needed can be distributed along the electrical network in a better and more efficient way. In order to avoid any kind o risk if the supply fails it will be implemented a controlled shutdown using the energy applied to the test specimen. The specimen when is loaded works like a spring. The potential energy is used to unload the own specimen using autonomous system working with batteries to allow the specimen unloading using electric brakes to unload smoothly the test specimen. A test for one of this winch system has been carried out at SerTec facilities during CTR stage. The Outcome of the Topic Manager for this technology after the CTR is:
• A range of control and failure scenarios were shown to be robustly controlled at winch loads up to the peak loads expected for test.
• Textile cable was demonstrated to be very low elongation
• Winch was demonstrated to be low vibration and high precision control
• Improvement opportunity:
• When operating in a manual control mode (to take up slack in the rope) a maximum applicable load should be incorporated in the system preventing any possible overload
• STATUS: The technology is fully proven but subsequent failure could affect GFEM Validation.

- Remote Data Acquisition Reception: The follow up of the test could be done in remote thanks to the system LINCE developed by TEAMS. LINCE is a tool for test follow-up which main advantages are:
• Data and video synchronization
• Calculated channels
• Independent access for each customer
• Replay option
• Data stored in the application and accessible to the customer
• Multi-platform free solution for the customer, there is no need to install proprietary applications in the customer
Normally during a test like the one developed in this proposal various stress engineers from different locations have to travel from their office to the place where the test is performed, that mean big costs in transportation which can be avoided if a tool like the one described in this WP can be used during the campaign.
To make this tool fully functional new functions will be developed. The deliverable a new version of this tool will be issued with new functions like the one listed below:
• Inspection & Damages reports available at the application. Document repository
• Unlimited number of simultaneous tests
• Instrumentation drawings available in the application.
• Security protocols implementation for a secure communication and data interchange
A functional test of the application has been be prepared by TEAMS for CTR stage. The Outcome of the Topic Manager for this technology after the CTR is:
• Presentation of live data viewing system:
• The LINCE system demonstrated a good level of maturity for a small demonstration test including interesting features such as the “replay” function. However the system has not been demonstrated with high volume data transfer and is not mature with regards to ensuring two way data feedback for the SPOC
• Improvement opportunity:
• Further development is required to address the issues raised above.
• Proposed data transfer confirmation
• Issue escalation buttons (Examples: Test hold, Emergency stop, SPOC attention request)
• High volume data demonstration

• STATUS: The technology is not yet fully mature, but failure would not affect GFEM Validation

- Infrared Thermography Applications: The infrared thermography, together with Thermoelastic Stress Analysis may be used in the evaluation of stress distribution in aeronautical components under mechanical loads. The most recent studies show that different methods of Thermoelastic Stress Analysis are capable of explaining the manner in which damage initiates and propagates in composite materials. With this ability of detection and analysis techniques it is possible a timely intervention and repair to prevent component failure.
The data recorded during the structural tests taken by gauges, belong to specific points where each gauge is situated, and therefore there may be deviations from the finite element model of tension design. When obtaining an image by infrared thermography of the behavior of a wide area, it can achieve the following advantages:
• Visualization of the level of tensions of a large area in just one image, which facilitates the interpretation of the results, since the result is a map with color coded grades of tension. This contrasts with the numerical values offered by the gauges.
• Verification of the results obtained with finite element models. This verification may enable a rapid change in the structural test configuration to make it more realistic or soon decide on a design change to avoid future higher costs.
• Optimization in the use of gauges: Depending on the tension field measured by IRT it will be possible to correct the position of the gauges, to place them in points of greatest interest, and not far away, as may indicate the theoretical model. Furthermore, the use of IRT will help put the just necessary gauges, instead of using too many of them to be sure to cover as many points as possible, with the associated additional cost.
• Improvement of calculations and design: based on a better understanding of the stress field by the visualization of the behavior of the specimen during the mechanical test it could lead to improved designs and increased safety margins reducing weights
All the studies have been carried out yet and a test of the application has been prepared by CTA to be done at CTR stage. The Outcome of the Topic Manager for this technology after the CTR is:
• Presentation IR thermography:
• The use of IR thermography was demonstrated by presentation including a test case with low strain ramps (incremental steps up to 2000 Micro-Strain).
• The technology has been developed through improved analysis methods and automated data acquisition. This has resulted in improved accuracy at low thermal values.
• The validation on test will be compromised due to the plan to maintain full protects for the BLADE wing upper cover.
• Improvement opportunity:
• When operating in a manual control mode (to take up slack in the rope) a maximum applicable load should be incorporated in the system preventing any possible overload.
• Consider alternative measurement location from upper cover (Lower leading edge or lower cover)

• STATUS: The technology is not yet fully mature, but failure would not affect GFEM Validation.

Potential Impact:
The WISDOM project addresses the JTI-CS-2012-02-SFWA-03-010 topic “BLADE wing structural test to derive test data for subsequent validation of GFEM modeling” within the SFWA ITD of Clean Sky. Therefore, the project will contribute to this ITD expected environmental impact which consists of putting greener products into the market that:
• Reduce the medium and long range aircraft fuel burn and aircraft emissions by around 10 to 20%.
• Reduce the medium and long range aircraft noise by 5 to 10 dB.
Furthermore, the project will contribute in terms of socioeconomic impact to ACARE’s latest goal of making the European aircraft industry meet society’s needs and win global leadership.

Impact of the project on the environment
Many studies have concluded the effectiveness of optimizing wing shape in order to delay transition from laminar to turbulent flow and thus reduce aircraft drag. Thus, estimations of a 20% reduction in drag through NLF technology have been presented. Benefits associated to drag reduction are a decrease in fuel burn a well as aircraft emissions and noise. Possible fuel savings of up to 30% for subsonic commercial aircraft have been suggested through successful NLF system development. An equivalent amount of reduction in CO2 emissions per passenger and km could be expected. A 58% decrease in NOx emissions and 16 dB reduction in noise (together with a 44% decrease in fuel burn) through combination of advanced composites, LF and very high bypass turbofans has been proved by
Boeing SUGAR team on a 737 size airliner.

Socioeconomic impact of the project
Air transport is a strategic sector for the Europe economy. Studies have shown that this industry accounts for approximately 2.5% of GDP, creates over 3 million jobs (direct and indirect) and contributes in excess of 30Bn to a positive trade balance for Europe. Moreover, based on projected growth over the next twenty years air transport could contribute an additional 1.8% of GDP. However, gradual worsening of the global economic situation, euro-dollar exchange rate, cost of oil and emerging new competitors are forcing the European aerospace sector to continuous efforts to maintain its position. Since despite extensive research both in Europe and in the US no usable LF control system has yet found its way on to commercial aircrafts, the WISDOM project will provide increased and differentiated technological capabilities to the European aircraft industry. The expected results will not only benefit aircraft manufacturers’ competitiveness but also their suppliers’, many of them SME’s who are experiencing a fierce concurrence from low cost competitors. The project will also contribute to sustainable growth requested by European citizens since highly qualified jobs will be maintained or created to fabricate new environmentally friendly products.

Contact

Cano Corral, Eduardo Alberto (business manager)
Tel.: +34917241775
Fax: +34917903532
E-mail
Record Number: 187873 / Last updated on: 2016-08-24