An efficient strategy for propagating sonic boom signatures from a near - field Computational Fluid Dynamics ( CFD ) solution to the mid - field is presented . The method is based on a high - order accurate finite - difference discretization of the 3D Euler equations on a specially designed curvilinear grid and a single sweep space marching solution algorithm . The new approach leads to more than a factor of two reduction in overall computational resources compared to the current method used to propagate near - field sonic booms to the ground . Accuracy and efficiency of the near - field to mid - field process is demonstrated using a selection of test cases from the AIAA Sonic Boom Prediction Workshops . Azimuthal dependence of nonlinear wave propagation from the near - field to mid - field is analyzed along with its effects on the ground level noise .