A simple, two-dimensional ray tracing scheme is developed and is applied to several propagation problems of importance to over-the-horizon radar. In particular, it is used as the basis of schemes for the simulation of oblique and backscatter ionograms. The efficiency of the scheme makes it ideal for applications where fast calculations are required, and an algorithm for inverting backscatter ionogram leading edges is developed as a particular example. ¿ 1998 American Geophysical Union