**4. Summary**

The focus of the paper is to evidence differences between results from PVDF sensors when they are placed within different surfaces of the thrust bearing. In particular, the pad passing frequency (PPF) was discovered when the rotating pads act across the surface of the sensors. Also observed was an increase in broadband noise associated with fluid motion generated by the rotating pads. Both of those observations are important for the measurement of the interaction force within a thrust bearing. The PVDF placement on the pad, on the other hand, provides signals free from the pad passing and broadband signals as a result of the changed reference frame. This significant reduction in the noise floor across the full frequency of rotational speeds tested is achieved without post processing filtering. Despite its promise, this latter configuration of the PVDF placement is by no means to be the optimal placement, as the interpretation of the PVDF output in terms of the force components on its surface and the dynamic response of the structure upon which the sensor is attached still require more sophisticated experimental and modelling work.
