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A set of experiments were carried out within an aeroacoustic wind tunnel facility to investigate parametrically the acoustic interactions of a propeller positioned above two flat plates of varying dimensions. A propeller was tested at a constant rotational rate of 7000 RPM in static conditions in three test configurations; an isolated propeller, a propeller interacting with a semi-infinite flat plate and a propeller interacting with a finite flat plate. The aerodynamic loading and far-field noise data were collected. The changes in magnitude and directivity of the overall sound pressure level as well as the first blade passing frequency tone were explored comprehensively for the different cases. The spectral content of selected cases of interest were examined in greater detail showing the impacts of acoustic scattering, diffraction, reflection and shielding when both flat plates are introduced. The results show that locations exist at which there is significant potential for noise attenuation in both the tonal and broadband noise content. Reductions of up to 11.6 dB in the overall sound pressure level and 19.9 dB in the first blade passing frequency were discovered.