To accelerate its processes for ground vibration testing, EADS-CASA recently implemented LMS Test.Lab, a complete software solution for test-based engineering combining high-speed multi-channel data acquisition with a suite of integrated testing, analysis, and report generation tools.
EADS-CASA’s aircraft testing process includes a series of tests to detect aircraft resonances as a verification of aircraft safety and reliability prior to the first actual flight tests. The LMS Test.Lab Ground Vibration Testing (GVT) solution includes integrated testing and analysis software and is based on interconnected LMS SCADAS III data-acquisition front ends, adding more than 700 channels, representing one of the largest channel count systems for aerospace dynamic testing.
EADS-CASA cooperated with LMS Engineering Services and Alava Ingenieros, LMS’ representative in Spain, to gain understanding of best practices in ground vibration testing and to accelerate the deployment of the LMS Test.Lab solution.
EADS-CASA Military Transport Aircraft Division, a division of EADS based in Madrid, Spain, deployed the LMS GVT systems to support the development of the Airbus A330 Multi Role Tanker Transport (MRTT), the aerial refueling tanker aircraft based on the civilian A330 aircraft.
The large basic fuel capacity of the standard A330-200 allowed developers to avoid installation of additional fuel tanks, freeing the entire cargo bay for use, with the possibility of incorporating LD3 or LD6 containers, military pallets, or any other type of load adapted to the plane.
The role of the LMS GVT system is important in identifying structural resonances and validation flutter models on the A330 MRTT. To support this, the LMS Test.Lab solution delivers a tight integration of all ground vibration methods, including mode appropriation, stepped sine, swept sine, and random testing.
The high channel count of the LMS GVT system allowed EADS-CASA to make all measurements for a complete aircraft configuration in a single test instead of the multiple series of tests required previously. In addition to saving time, this also reduces the risk of setup mistakes and data management errors.
Online monitoring enabled EADS-CASA engineers to view results in real time as tests were being run. Engineers were able to check the validity of measurements and correlate test data within simulation results instantly instead of waiting hours or days for post-processing. This allowed engineers to immediately identify the root cause of problems and better determine corrective actions.
Animation tools within the software such as deflection shapes show how parts bend and twist at various frequencies, and the LMS PolyMAX tool analyzes modal test data to identify resonances. By not relying on subjective judgments of individual engineers, PolyMAX also yields more accurate and consistent results.
In the frequency band under investigation, modes are often very close to one another; therefore, quickly identifying the critical modes represents an important challenge for the engineering team. The integrated LMS Test.Lab GVT solution offers the ability to quickly find and identify the critical modes in a reliable way, enabling the company to significantly shorten the turnaround time for these tests.
To support the deployment of the GVT system in a time-critical aircraft development process, EADS-CASA relied upon a team of Alava Ingenieros and LMS engineers, which supported the deployment via careful system installation and integration, extensive user training, and on-the-job assistance. EADS-CASA and LMS cooperated to exchange know-how and best practices regarding the application of multiple excitation techniques like mode appropriation, stepped sine, swept sine, and random testing.
The A330 MRTT is being assessed for mission requirements throughout the world and has been selected as the Future Strategic Tanker Aircraft for the U.K. Royal Air Force and been ordered by the Royal Australian Air Force.
The aircraft can be provided with a combination of wing pod and/or fuselage hose and drogue units and/or the EADS-CASA advanced refueling boom system.