Communication-system blackout during reentry of large vehicles

Much of the theoretical research on reentry blackout is in a format difficult for the communications design engineer to use in his system analysis. This paper derives simplified equations for the average sheath power loss that may be added (in dB) to the usual space loss to obtain an approximate total propagation loss. The plasma and sheath properties are discussed in detail but largely without supporting mathematics, in order to give the design engineer a better understanding of the overall problem. For the same reason and to provide insight into the final results, the average radiated power is found, using both intuitive and rigorous techniques. Several graphs of plasma properties are included in the development as an aid to numerical computations, and results are compared with the work of other authors.