Supersonic axisymmetric base flows are prototypical for flows behind projectiles and missiles. There is evidence that large (turbulent) coherent structures exist in these flows and strongly influence the mean flow. The objective of the present investigation is to evaluate if and how successful passive flow control techniques modify the large structures and the mean flow. To this end, numerical simulations using two hybrid RANS/LES methods, the Flow Simulation Methodology (FSM) and Detached Eddy Simulations (DES), were employed to investigate the supersonic base flow at ReD = 3.3 × 10 6 and Ma = 2.46. As a passive control method, boat-tailing is studied. The obtained mean flow data and the turbulent coherent structures are compared to available experimental results and to simulations without flow control.