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Wing Anti-Icing Systems (WAIS) are integral part of a wing design. Their presence ensures safety in all-weather conditions. In standard designs, the WAIS are fitted in the slat internal structure and runs throughout its span in between the ribs. Given its critical function, such a system has to pass qualification test. The test specification is dictated by international standards. In the case discussed in this article, the standard adopted is the RTCA DO-160G “Environmental Conditions and Test Procedures for Airborne Equipment”. In particular, the work presented here concerns with the Vibration environmental test. The standard prescribes a number of dynamic tests to be carried out on the AIS: random, shock and sine excitation tests have to be performed in order to study their effect on the parts composing the Anti-Icing System. The standard prescribes vibration levels at the attachment locations of the AIS to the wings' ribs.

The paper will introduce some recent advances in vibration testing and modal analysis of airplanes. Recently, a very promising parameter estimation method became available, that has the potential to become the new standard. The main advantage of this so-called PolyMAX method is that it yields extremely clear stabilization diagrams even for broadband and high-order analyses. The method will be applied to two aircraft cases: a Ground Vibration Test using broadband shaker excitation on a small composite aircraft and in-flight data using natural turbulences as excitation. These two data sets allow illustrating both the classical Frequency Response Function based as well as the operational output-only modal analysis process.

One of the practical consequences of the development of low CO₂ emission cars is that many of the traditional NVH sound engineering processes no longer apply and must be revisited. Different and new sound sources, new constraints on vehicle body design (e.g., due to weight) and new sound perception characteristics make that the NVH knowledge built on generations of internal combustion-powered vehicles cannot be simply transferred to Hybrid and Electric Vehicles (HEV). Hence, the applicability of tools must be reviewed and extensions need to be developed where necessary. This paper focuses on sound synthesis tools as developed for ICE-powered vehicles. Because of the missing masking effect and the missing intake and exhaust noise of the Internal Combustion Engine (ICE) in electric vehicles, on one hand electric vehicles are quieter than traditional vehicles.