The session on acoustic noise test has been particularly popular. 5 papers were presented with main focus on direct acoustic field approach, which is a very active area of research and development. There, new metric to quantify the uniformity and diffusiveness of the pressure field was proposed; advancement of MIMO test control performance was demonstrated via detailed assessment of test data, complemented by the high fidelity simulation developed specifically for this purpose.

We can notice that there is still some work to do on the launcher acoustic field representativeness.

Another presenter showed an end-to-end validation covering test and simulation tools based on a different acoustic noise control and generation system. Notwithstanding the progress shown on direct acoustic field approach in practice, one presenter has highlighted the fundamental aspect on wave incidence which is important in both the understanding and correct simulation of the field and structural responses.

On the more conventional acoustic noise test approach in a reverberant chamber, the last paper of the session rightly highlighted the need to account for the influence of sound absorption of the test article to ensure the safety and needed performance are reached.

The Mechanical test campaign session provided an overview of the verification tests performed on a number of Earth Observation spacecrafts (EarthCare, FLEX and Sentinel 6), as well as scientific (PLATO), but also a very specific application with the International Berthing and Docking Mechanism for ISS. Presenters covered a wide range of topics, from remarking the importance of refined test predictions and advanced check of test instrumentation response (e.g. via auto-MAC calculation tool), to highlighting the option of qualifying versus quasi-static loads in the frame of sine vibration test (with QSL limits reached in a frequency range below the first mode), to implementation of a random environment verification approach to cope with launcher requirements defined late in the development.

At the session dedicated to launchers, several presentations were dedicated to re-usable launchers which is now an important topic for the European community. The challenges of developing such a system were described for the Calisto vehicle and in particular the qualification wrt the dynamic environment. For re-usable vehicles, structural health monitoring could be a great asset in order to improve their reliability and efficiency. A system was tested to demonstrate it could withstand all the environmental conditions it could face on a re-usable launcher.

Other types of mechanical environment on launchers were discussed: first the methodologies needed to optimise acoustic fairing protections in order to offer a better comfort to the payloads, and a study on the correlation of assembly fluxes (created when 2 interfaces with imperfect geometries are bolted together) which need to be taken into account for structure sizing.

The session on thermal test means included the presentation of specific thermal test facilities, like the large cryogenic facility in CSL, used to cycle solar arrays for Jupiter missions, or a specific facility for mechanical testing of adhesive at cryogenic temperatures. Instrumentation techniques were also presented, in particular the development of infrared thermography at low temperature. Development of a new test facility in IABG to support optical tests was also presented.

Multi-axis vibration was presented as a promising new approach, with comparison between responses obtained in one axis, 3 axes and 6 degrees of freedom vibration. Vibration testing with empty tanks was also presented with the experience of JUICE testing, including discussion of the conditions under which such approach can be acceptable in terms of model correlation, sensitivity analyses to demonstrate robustness, and verification at lower level of integration (structure, tanks, …).