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A passive flow control technique of utilizing an equilateral triangular trip close to the leading edge was developed and tested for a micro-scale Eppler E423 airfoil at a Reynolds number based on the chord of 40 000. The analysis was carried out via high-order wall-resolved large eddy simulation using the computational solver HpMusic. Angles of attack of 5° and 20° were tested. It was shown that at an angle of attack of 5°, the trip height of two times the local boundary layer thickness outperformed existing passive flow control techniques from the literature by almost a factor of five in terms of the lift-to-drag ratio. To understand the underlying physics which allowed the trip to provide this very significant performance benefit, metrics such as pressure coefficient profiles, oil flows, iso-surfaces of Q-criteria, and leading-edge flow behavior were examined. It was found that this trip configuration simultaneously removed the flow separation regions on both the suction and pressure sides of the wing.