A new hybrid RANS/LES method DDES SST KD is proposed, aimed at computations of flows with separation and laminar-turbulent transition in the attached boundary layer. The method is based on a new transition model which uses the SST turbulence model and k-ω KD transition model as a basis. The resulting approach is then tested on a drag crisis problem flows around a circular cylinder and a sphere. The results show that the proposed method is an improvement relative to DDES SST.