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Download or read book Trailblazer II Rocket Tests on the Reentry Plasma Sheath written by John F. Lennon and published by . This book was released on 1973 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: The properties of the reentry plasma sheath are being studied by AFCRL in a series of Trailblazer II rocket flights. This program is divided into two phases. The first phase has been concerned with the structure of the ionized layer that forms around the test vehicles during reentry and in particular its effect on electromagnetic signals, while the second phase is concerned with enhancing microwave transmitter performance under such conditions by introducing chemicals into the flow to reduce the free electron concentrations. This report surveys some aspects of the first phase which consisted of three flights. The first part of the report describes the flight performance of the vehicles including trajectory, velocity history, aerodynamic heating, spin-and-precession, and overall orientation of each payload during its reentry, while the second part presents a theoretical description of the high temperature shock layer for the various flight conditions. Since the purpose of the calculations was to obtain predictions of experimental performance, a number of different models were used. The resulting flow properties are presented in some detail; in particular, the various electron density distributions are shown both in the nose region and around the vehicle. These results are analyzed and then compared with the extensive experimental data. On the conical afterbody where three-dimensional effects due to vehicle angle of attack become important, the observed conditions could not be completely represented by the theoretical models--all of which assumed the flow to be axisymmetric. The general conclusion, however, is that the theoretical properties satisfactorily predict the actual test performance for a wide range of situations. (Author).