DARcorporation engineers have the capability to model, simulate and analyze aircraft external modifications on aircraft. External modifications include antenna, radome and weather equipment. Utilizing computational fluid dynamics (CFD) simulations at subsonic and/or transonic speeds in both steady and unsteady conditions, detailed surface pressure distributions and loads are calculated for use in finite element analysis (FEA) structural analysis and sizing. Through CFD analysis and FEA, critical flight conditions are identified and recommendations for structural improvement are made. CFD simulation also helps to determine the presence of adverse effects on aircraft stability and control due to the external modification.  External modification to aircraft could cause unsteady flow fluctuations too, which can be detected using velocity profile, streamlines and vorticity plots.