Research Shake Test on an Airbus Helicopter technology demonstrator

Kurzfassung

This paper comprises the work of the research shake test on an AIRBUS Helicopters full scale technology demonstrator. The test on the entire helicopter was performed by the vibration test team of the DLR-Institute of Aeroelasticity within three weeks in March/April 2023 at AIRBUS Helicopters Deutschland GmbH (AHD) in Donauwörth, Germany. In addition to the shake test, some specific test runs with the landing skid partially or fully on ground were also carried out as a preparation for the ground resonance tests in operation with rotor turning conducted by AIRBUS Helicopters. The test specimen is a helicopter technology demonstrator. Like a ground vibration test on a fixed wing aircraft [1], the shake test shall provide the necessary experimental data to achieve permit to fly for the helicopter demonstrator. To this end, the test results shall enable the quantification of vibration transmission from main rotor hub to various positions on the fuselage, but also the adjustment of the dynamic models of the structure. An equivalent modal substitute model was identified for the reference configuration. This modal model was established with a dedicated software and database which can be used for visualization and correlation of modal analysis results. This software can also provide scatter and nonlinear trends in modal analysis results. Next to the reference configuration, more than 20 other structural configurations have been tested, for which frequency response functions and specific modal parameters were provided in order to conduct experimental sensitivity studies. The paper will focus on the hardware and software tools as well as the data analysis procedures applied during the tests.