The purpose of this work is to examine in detail the flow field characteristics of the thermally choked ram accelerator, a novel concept of space launcher. The data derived from these CFD calculations were used to implement a one-dimensional computer code, which has been developed to predict the thrust of this vehicle. The predicted thrust and velocity agree well with values derived from representative experiments at the University of Washington 38-mm-bore facility. The code, which requires simple data input and very low computer capabilities, provides an easy and rapid access to the...