During flight, passenger comfort is affected by noise emissions from various aircraft systems. Apart from jet engines one of the main sources of noise within the fuselage is the power control unit (PCU) for high-lift actuation. In preparation for take-off and landing this hydraulic motor is responsible for the extension and retraction of the slats and flaps. Along with the increase in operating pressure from 206bar (3,000psi) to 345bar (5,000psi) noise and vibration induced by fluid power systems became more striking. Consequently the aim of the BMWI founded research project “Move On” was to reduce the emissions of Liebherr’s power control unit. The results of these research activities are presented within this paper. It is shown how the noise emissions could be reduced in a secondary controlled hydraulic motor by means of a valve-plate and structure optimization. In addition the results of a noise measurement campaign, conducted by Airbus on an A350, are presented.