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High-lift devices often generate an unsteady flow field producing both broadband and tonal noise which radiates from the aircraft. In particular, the leading edge slat is often a dominant contributor to the noise signature. An experimental study of a simplified unswept high-lift configuration, the 30P30N, has been conducted to understand and identify the various flow-induced noise sources around the slat. Closed-wall wind tunnel tests are performed in the Florida State Aeroacoustic Tunnel (FSAT) to characterize the slat cove flow field using a combination of surface and off-body measurements. Mean surface pressures compare well with numerical predictions for the free-air configuration. Consistent with previous measurements and computations for 2D high-lift configurations, the frequency spectra of unsteady surface pressures on the slat surface display several narrowband peaks that decrease in strength as the angle of attack is increased. At positive angles of attack, there are four prominent peaks. The three higher frequency peaks correspond, approximately, to a harmonic sequence related to a feedback resonance involving unstable disturbances in the slat cove shear layer. The Strouhal numbers associated with these three peaks are nearly insensitive to the range of flow speeds (41-58 m/s) and the angles of attack tested (3-8.5 • ). The first narrow-band peak has an order of magnitude lower frequency than the remaining peaks and displays noticeable sensitivity to the angle of attack. Stereoscopic particle image velocimetry (SPIV) measurements provide supplementary information about the shear layer characteristics and turbulence statistics that may be used for validating numerical simulations. Nomenclature bAirfoil span [m] c Airfoil stowed chord [m] C p Coefficient of pressure f Frequency [Hz] G Autospectral density function [Pa 2 /Hz] L γ Coherence length [m] m, n Transducer indicies N Total number of transducers P SD Power spectral density [Pa 2 /Hz] q Dynamic freestream pressure [Pa] Re c Reynolds number based on c s Slat chord [m] St s Strouhal number based on s T KE Turbulent kinetic energy U ∞ Freestream velocity [m/s] |V | Velocity vector magnitude [m/s] u, v, w Velocity components [m/s] x Chordwise distance [m] ∆z Spanwise distance [m] α Geometric angle of attack [ • ] γ 2 Ordinary coherence function ω z Spanwise vorticity [1/s] · Ensemble average of quantity Superscript: () * Nondimensional units () ′ Fluctuating quantity

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